Print methods in Java syntax. Simplify computing the message JEP-8220715-NPE_messages
authorgoetz
Wed, 10 Apr 2019 08:26:23 +0200
branchJEP-8220715-NPE_messages
changeset 57319 aa400d41ebd6
parent 57318 cb67307942f3
Print methods in Java syntax. Simplify computing the message Summary: Cleanup test: arrange according to messages and topics. Add test cases.
src/hotspot/share/interpreter/bytecodeUtils.cpp
src/hotspot/share/interpreter/bytecodeUtils.hpp
src/hotspot/share/prims/jvm.cpp
test/hotspot/jtreg/runtime/exceptionMsgs/NullPointerException/NullPointerExceptionTest.java
--- a/src/hotspot/share/interpreter/bytecodeUtils.cpp	Wed Apr 10 08:15:45 2019 +0200
+++ b/src/hotspot/share/interpreter/bytecodeUtils.cpp	Wed Apr 10 08:26:23 2019 +0200
@@ -32,22 +32,10 @@
 #include "utilities/events.hpp"
 
 /*
- * Returns the name of the klass that is described at constant pool
+ * Prints the name of the method that is described at constant pool
  * index cp_index in the constant pool of method 'method'.
  */
-char const* MethodBytecodePrinter::get_klass_name(Method* method, int cp_index) {
-  ConstantPool* cp = method->constants();
-  int class_index = cp->klass_ref_index_at(cp_index);
-  Symbol* klass = cp->klass_at_noresolve(class_index);
-
-  return klass->as_klass_external_name();
-}
-
-/*
- * Returns the name of the method that is described at constant pool
- * index cp_index in the constant pool of method 'method'.
- */
-char const* MethodBytecodePrinter::get_method_name(Method* method, int cp_index) {
+static void print_method_name(outputStream *os, Method* method, int cp_index) {
   ConstantPool* cp = method->constants();
   int class_index = cp->klass_ref_index_at(cp_index);
   Symbol* klass = cp->klass_at_noresolve(class_index);
@@ -58,16 +46,17 @@
   Symbol* name = cp->symbol_at(name_index);
   Symbol* signature = cp->symbol_at(type_index);
 
-  stringStream ss;
-  ss.print("%s.%s%s", klass->as_klass_external_name(), name->as_C_string(), signature->as_C_string());
-  return ss.as_string();
+  signature->print_as_signature_external_return_type(os);
+  os->print(" %s.%s(", klass->as_klass_external_name(), name->as_C_string());
+  signature->print_as_signature_external_parameters(os);
+  os->print(")");
 }
 
 /*
- * Returns the name of the field that is described at constant pool
+ * Prints the name of the field that is described at constant pool
  * index cp_index in the constant pool of method 'method'.
  */
-char const* MethodBytecodePrinter::get_field_and_class(Method* method, int cp_index) {
+static void print_field_and_class(outputStream *os, Method* method, int cp_index) {
   ConstantPool* cp = method->constants();
   int class_index = cp->klass_ref_index_at(cp_index);
   Symbol* klass = cp->klass_at_noresolve(class_index);
@@ -76,16 +65,14 @@
   int name_index = cp->name_ref_index_at(name_and_type_index);
   Symbol* name = cp->symbol_at(name_index);
 
-  stringStream ss;
-  ss.print("%s.%s", klass->as_klass_external_name(), name->as_C_string());
-  return ss.as_string();
+  os->print("%s.%s", klass->as_klass_external_name(), name->as_C_string());
 }
 
 /*
  * Returns the name of the field that is described at constant pool
  * index cp_index in the constant pool of method 'method'.
  */
-char const* MethodBytecodePrinter::get_field_name(Method* method, int cp_index) {
+static char const* get_field_name(Method* method, int cp_index) {
   ConstantPool* cp = method->constants();
   int name_and_type_index = cp->name_and_type_ref_index_at(cp_index);
   int name_index = cp->name_ref_index_at(name_and_type_index);
@@ -93,6 +80,54 @@
   return name->as_C_string();
 }
 
+static void print_local_var(outputStream *os, int bci, Method* method, int slot) {
+  if (method->has_localvariable_table()) {
+    for (int i = 0; i < method->localvariable_table_length(); i++) {
+      LocalVariableTableElement* elem = method->localvariable_table_start() + i;
+      int start = elem->start_bci;
+      int end = start + elem->length;
+
+      if ((bci >= start) && (bci < end) && (elem->slot == slot)) {
+        ConstantPool* cp = method->constants();
+        char *var =  cp->symbol_at(elem->name_cp_index)->as_C_string();
+        os->print("%s", var);
+
+        return;
+      }
+    }
+  }
+
+  // Handle at least some cases we know.
+  if (!method->is_static() && (slot == 0)) {
+    os->print("this");
+  } else {
+    int curr = method->is_static() ? 0 : 1;
+    SignatureStream ss(method->signature());
+    int param_index = 0;
+    bool found = false;
+
+    for (SignatureStream ss(method->signature()); !ss.is_done(); ss.next()) {
+      if (ss.at_return_type()) {
+        continue;
+      }
+      int size = type2size[ss.type()];
+      if ((slot >= curr) && (slot < curr + size)) {
+        found = true;
+        break;
+      }
+      param_index += 1;
+      curr += size;
+    }
+
+    if (found) {
+      os->print("<parameter%d>", 1 + param_index);
+    } else {
+      // This is the best we can do.
+      os->print("<local%d>", slot);
+    }
+  }
+}
+
 TrackingStackEntry::TrackingStackEntry(BasicType type) : _entry(INVALID + type * SCALE) { }
 
 TrackingStackEntry::TrackingStackEntry(int bci, BasicType type) : _entry(bci + type * SCALE) {
@@ -105,7 +140,7 @@
 }
 
 BasicType TrackingStackEntry::get_type() {
-  return BasicType (_entry / SCALE);
+  return BasicType(_entry / SCALE);
 }
 
 TrackingStackEntry TrackingStackEntry::merge(TrackingStackEntry other) {
@@ -184,120 +219,6 @@
   return _stack.at(get_size() - slot - 1);
 }
 
-
-
-static TrackingStackSource createInvalidSource(int bci) {
-  return TrackingStackSource(TrackingStackSource::INVALID, bci, "invalid");
-}
-
-static TrackingStackSource createLocalVarSource(int bci, Method* method, int slot) {
-  // We assume outermost caller has ResourceMark.
-  stringStream reason;
-
-  if (method->has_localvariable_table()) {
-    for (int i = 0; i < method->localvariable_table_length(); i++) {
-      LocalVariableTableElement* elem = method->localvariable_table_start() + i;
-      int start = elem->start_bci;
-      int end = start + elem->length;
-
-      if ((bci >= start) && (bci < end) && (elem->slot == slot)) {
-        ConstantPool* cp = method->constants();
-        char *var =  cp->symbol_at(elem->name_cp_index)->as_C_string();
-        if (strlen(var) == 4 && strcmp(var, "this") == 0) {
-          reason.print("this");
-        } else {
-          reason.print("%s", var);
-        }
-
-        return TrackingStackSource(TrackingStackSource::LOCAL_VAR, bci, reason.as_string());
-      }
-    }
-  }
-
-  // Handle at least some cases we know.
-  if (!method->is_static() && (slot == 0)) {
-    reason.print("this");
-  } else {
-    int curr = method->is_static() ? 0 : 1;
-    SignatureStream ss(method->signature());
-    int param_index = 0;
-    bool found = false;
-
-    for (SignatureStream ss(method->signature()); !ss.is_done(); ss.next()) {
-      if (ss.at_return_type()) {
-        continue;
-      }
-
-      int size = type2size[ss.type()];
-
-      if ((slot >= curr) && (slot < curr + size)) {
-        found = true;
-        break;
-      }
-
-      param_index += 1;
-      curr += size;
-    }
-
-    if (found) {
-      reason.print("<parameter%d>", 1 + param_index);
-    } else {
-      // This is the best we can do.
-      reason.print("<local%d>", slot);
-    }
-  }
-
-  return TrackingStackSource(TrackingStackSource::LOCAL_VAR, bci, reason.as_string());
-}
-
-
-static TrackingStackSource createConstantSource(int bci, const char *text) {
-  return TrackingStackSource(TrackingStackSource::CONSTANT, bci, text);
-}
-
-static TrackingStackSource createArraySource(int bci, TrackingStackSource const& array_source,
-                                             TrackingStackSource const& index_source) {
-  // We assume outermost caller has ResourceMark.
-  stringStream reason;
-
-  if (array_source.get_type() != TrackingStackSource::INVALID) {
-    reason.print("%s", array_source.as_string());
-  } else {
-    reason.print("array");
-  }
-  if (index_source.get_type() != TrackingStackSource::INVALID) {
-    reason.print("[%s]", index_source.as_string());
-  } else {
-    reason.print("[...]");
-  }
-
-  return TrackingStackSource(TrackingStackSource::ARRAY_ELEM, bci, reason.as_string());
-}
-
-static TrackingStackSource createFieldSource(int bci, Method* method, int cp_index,
-                                             TrackingStackSource const& object_source) {
-  // We assume outermost caller has ResourceMark.
-  stringStream reason;
-
-  // GLGL We could also print the type of the field. Should we do that?
-  //MethodBytecodePrinter::get_klass_name(method, cp_index)
-  if (object_source.get_type() != TrackingStackSource::INVALID) {
-    reason.print("%s.", object_source.as_string());
-  }
-  reason.print("%s", MethodBytecodePrinter::get_field_name(method, cp_index));
-
-  return TrackingStackSource(TrackingStackSource::FIELD_ELEM, bci, reason.as_string());
-}
-
-static TrackingStackSource createStaticFieldSource(int bci, Method* method, int cp_index) {
-  // We assume outermost caller has ResourceMark.
-  stringStream reason;
-  reason.print("static %s",
-               MethodBytecodePrinter::get_field_and_class(method, cp_index));
-
-  return TrackingStackSource(TrackingStackSource::FIELD_ELEM, bci, reason.as_string());
-}
-
 TrackingStackCreator::TrackingStackCreator(Method* method, int bci) : _method(method) {
   ConstMethod* const_method = method->constMethod();
 
@@ -912,128 +833,27 @@
   return len;
 }
 
-TrackingStackSource TrackingStackCreator::get_source(int bci, int slot, int max_detail) {
-  assert(bci >= 0, "BCI too low");
-  assert(bci < get_size(), "BCI to large");
-
-  if (max_detail <= 0) {
-    return createInvalidSource(bci);
-  }
-
-  if (_stacks->at(bci) == NULL) {
-    return createInvalidSource(bci);
+int TrackingStackCreator::get_NPE_null_slot(int bci) {
+  // If this NPE was created via reflection, we have no real NPE.
+  if (_method->method_holder() == SystemDictionary::reflect_NativeConstructorAccessorImpl_klass()) {
+    return -2;
   }
-
-  TrackingStack* stack = _stacks->at(bci);
-  assert(slot >= 0, "Slot nr. too low");
-  assert(slot < stack->get_size(), "Slot nr. too large");
-
-  TrackingStackEntry entry = stack->get_entry(slot);
-
-  if (!entry.has_bci()) {
-    return createInvalidSource(bci);
-  }
-
   // Get the bytecode.
-  int source_bci = entry.get_bci();
   address code_base = _method->constMethod()->code_base();
-  Bytecodes::Code code = Bytecodes::java_code_at(_method, code_base + source_bci);
-  bool is_wide = false;
-  int pos = source_bci + 1;
-
+  Bytecodes::Code code = Bytecodes::java_code_at(_method, code_base + bci);
+  int pos = bci + 1;
   if (code == Bytecodes::_wide) {
-    is_wide = true;
-    code = Bytecodes::java_code_at(_method, code_base + source_bci + 1);
+    code = Bytecodes::java_code_at(_method, code_base + bci + 1);
     pos += 1;
   }
 
   switch (code) {
-    case Bytecodes::_iload:
-    case Bytecodes::_lload:
-    case Bytecodes::_fload:
-    case Bytecodes::_dload:
-    case Bytecodes::_aload: {
-      int index;
-
-      if (is_wide) {
-        index = Bytes::get_Java_u2(code_base + source_bci + 2);
-      } else {
-        index = *(uint8_t*) (code_base + source_bci + 1);
-      }
-
-      return createLocalVarSource(source_bci, _method, index);
-    }
-
-    case Bytecodes::_iload_0:
-    case Bytecodes::_lload_0:
-    case Bytecodes::_fload_0:
-    case Bytecodes::_dload_0:
-    case Bytecodes::_aload_0:
-      return createLocalVarSource(source_bci, _method, 0);
-
-    case Bytecodes::_iload_1:
-    case Bytecodes::_lload_1:
-    case Bytecodes::_fload_1:
-    case Bytecodes::_dload_1:
-    case Bytecodes::_aload_1:
-      return createLocalVarSource(source_bci, _method, 1);
-
-    case Bytecodes::_iload_2:
-    case Bytecodes::_lload_2:
-    case Bytecodes::_fload_2:
-    case Bytecodes::_dload_2:
-    case Bytecodes::_aload_2:
-      return createLocalVarSource(source_bci, _method, 2);
-
-    case Bytecodes::_lload_3:
-    case Bytecodes::_iload_3:
-    case Bytecodes::_fload_3:
-    case Bytecodes::_dload_3:
-    case Bytecodes::_aload_3:
-      return createLocalVarSource(source_bci, _method, 3);
-
-    case Bytecodes::_aconst_null:
-      return createConstantSource(source_bci, "null");
-    case Bytecodes::_iconst_m1:
-      return createConstantSource(source_bci, "-1");
-    case Bytecodes::_iconst_0:
-      return createConstantSource(source_bci, "0");
-    case Bytecodes::_iconst_1:
-      return createConstantSource(source_bci, "1");
-    case Bytecodes::_iconst_2:
-      return createConstantSource(source_bci, "2");
-    case Bytecodes::_iconst_3:
-      return createConstantSource(source_bci, "3");
-    case Bytecodes::_iconst_4:
-      return createConstantSource(source_bci, "4");
-    case Bytecodes::_iconst_5:
-      return createConstantSource(source_bci, "5");
-    case Bytecodes::_lconst_0:
-      return createConstantSource(source_bci, "0L");
-    case Bytecodes::_lconst_1:
-      return createConstantSource(source_bci, "1L");
-    case Bytecodes::_fconst_0:
-      return createConstantSource(source_bci, "0.0f");
-    case Bytecodes::_fconst_1:
-      return createConstantSource(source_bci, "1.0f");
-    case Bytecodes::_fconst_2:
-      return createConstantSource(source_bci, "2.0f");
-    case Bytecodes::_dconst_0:
-      return createConstantSource(source_bci, "0.0");
-    case Bytecodes::_dconst_1:
-      return createConstantSource(source_bci, "1.0");
-    case Bytecodes::_bipush: {
-      jbyte con = *(jbyte*) (code_base + source_bci + 1);
-      stringStream ss;
-      ss.print("%d", con);
-      return createConstantSource(source_bci, ss.as_string());
-    }
-    case Bytecodes::_sipush: {
-      u2 con = Bytes::get_Java_u2(code_base + source_bci + 1);
-      stringStream ss;
-      ss.print("%d", con);
-      return createConstantSource(source_bci, ss.as_string());
-    }
+    case Bytecodes::_getfield:
+    case Bytecodes::_arraylength:
+    case Bytecodes::_athrow:
+    case Bytecodes::_monitorenter:
+    case Bytecodes::_monitorexit:
+      return 0;
     case Bytecodes::_iaload:
     case Bytecodes::_faload:
     case Bytecodes::_aaload:
@@ -1041,259 +861,26 @@
     case Bytecodes::_caload:
     case Bytecodes::_saload:
     case Bytecodes::_laload:
-    case Bytecodes::_daload: {
-      TrackingStackSource array_source = get_source(source_bci, 1, max_detail - 1);
-      TrackingStackSource index_source = get_source(source_bci, 0, max_detail - 1);
-      return createArraySource(source_bci, array_source, index_source);
-    }
-
-    case Bytecodes::_invokevirtual:
-    case Bytecodes::_invokespecial:
-    case Bytecodes::_invokestatic:
-    case Bytecodes::_invokeinterface: {
-        int cp_index = Bytes::get_native_u2(code_base + pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
-        // We assume outermost caller has ResourceMark.
-        stringStream reason;
-        if (max_detail == 5 /* Todo: introduce a constant ... */) {
-          reason.print("The return value of '%s'", MethodBytecodePrinter::get_method_name(_method, cp_index));
-        } else {
-          reason.print("%s", MethodBytecodePrinter::get_method_name(_method, cp_index));
-        }
-        return TrackingStackSource(TrackingStackSource::METHOD, source_bci, reason.as_string());
-    }
-
-    case Bytecodes::_getstatic:
-      return createStaticFieldSource(source_bci, _method,
-                                     Bytes::get_native_u2(code_base + pos) + ConstantPool::CPCACHE_INDEX_TAG);
-
-    case Bytecodes::_getfield: {
-      int cp_index = Bytes::get_native_u2(code_base + pos) + ConstantPool::CPCACHE_INDEX_TAG;
-      TrackingStackSource object_source = get_source(source_bci, 0, max_detail - 1);
-      return createFieldSource(source_bci, _method, cp_index, object_source);
-    }
-
-    default:
-      return createInvalidSource(bci);
-  }
-}
-
-int TrackingStackCreator::get_null_pointer_slot(int bci, char const** reason) {
-  // If this NPE was created via reflection, we have no real NPE.
-  if (_method->method_holder() == SystemDictionary::reflect_NativeConstructorAccessorImpl_klass()) {
-    return -2;
-  }
-
-  // Get the bytecode.
-  address code_base = _method->constMethod()->code_base();
-  Bytecodes::Code code = Bytecodes::java_code_at(_method, code_base + bci);
-  int pos = bci + 1;
-
-  if (code == Bytecodes::_wide) {
-    code = Bytecodes::java_code_at(_method, code_base + bci + 1);
-    pos += 1;
-  }
-
-  int result = -1;
-
-  switch (code) {
-    case Bytecodes::_iaload:
-      if (reason != NULL) {
-        *reason = "Can not load from null int array.";
-      }
-
-      result = 1;
-      break;
-
-    case Bytecodes::_faload:
-      if (reason != NULL) {
-        *reason = "Can not load from null float array.";
-      }
-
-      result = 1;
-      break;
-
-    case Bytecodes::_aaload:
-      if (reason != NULL) {
-        *reason = "Can not load from null object array.";
-      }
-
-      result = 1;
-      break;
-
-    case Bytecodes::_baload:
-      if (reason != NULL) {
-        *reason = "Can not load from null byte/boolean array.";
-      }
-
-      result = 1;
-      break;
-
-    case Bytecodes::_caload:
-      if (reason != NULL) {
-        *reason = "Can not load from null char array.";
-      }
-
-      result = 1;
-      break;
-
-    case Bytecodes::_saload:
-      if (reason != NULL) {
-        *reason = "Can not load from null short array.";
-      }
-
-      result = 1;
-      break;
-
-    case Bytecodes::_laload:
-      if (reason != NULL) {
-        *reason = "Can not load from null long array.";
-      }
-
-      result = 1;
-      break;
-
     case Bytecodes::_daload:
-      if (reason != NULL) {
-        *reason = "Can not load from null double array.";
-      }
-
-      result = 1;
-      break;
-
+      return 1;
     case Bytecodes::_iastore:
-      if (reason != NULL) {
-        *reason = "Can not store to null int array.";
-      }
-
-      result = 2;
-      break;
-
-    case Bytecodes::_lastore:
-      if (reason != NULL) {
-        *reason = "Can not store to null long array.";
-      }
-
-      result = 3;
-      break;
-
     case Bytecodes::_fastore:
-      if (reason != NULL) {
-        *reason = "Can not store to null float array.";
-      }
-
-      result = 2;
-      break;
-
-    case Bytecodes::_dastore:
-      if (reason != NULL) {
-        *reason = "Can not store to null double array.";
-      }
-
-      result = 3;
-      break;
-
     case Bytecodes::_aastore:
-      if (reason != NULL) {
-        *reason = "Can not store to null object array.";
-      }
-
-      result = 2;
-      break;
-
     case Bytecodes::_bastore:
-      if (reason != NULL) {
-        *reason = "Can not store to to null byte/boolean array.";
-      }
-
-      result = 2;
-      break;
-
     case Bytecodes::_castore:
-      if (reason != NULL) {
-        *reason = "Can not store to to null char array.";
-      }
-
-      result = 2;
-      break;
-
     case Bytecodes::_sastore:
-      if (reason != NULL) {
-        *reason = "Can not store to null short array.";
-      }
-
-      result = 2;
-      break;
-
-    case Bytecodes::_getfield:
-      {
-        if (reason != NULL) {
-          int cp_index = Bytes::get_native_u2(code_base + pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
-          ConstantPool* cp = _method->constants();
-          int name_and_type_index = cp->name_and_type_ref_index_at(cp_index);
-          int name_index = cp->name_ref_index_at(name_and_type_index);
-          Symbol* name = cp->symbol_at(name_index);
-          stringStream ss;
-          ss.print("Can not read field '%s'.", name->as_C_string());
-          *reason = ss.as_string();
-        }
-
-        result = 0;
-      }
-
-      break;
-
-    case Bytecodes::_arraylength:
-      if (reason != NULL) {
-        *reason = "Can not read the array length.";
-      }
-
-      result = 0;
-      break;
-
-    case Bytecodes::_athrow:
-      if (reason != NULL) {
-        *reason = "Can not throw a null exception object.";
-      }
-
-      result = 0;
-      break;
-
-    case Bytecodes::_monitorenter:
-      if (reason != NULL) {
-        *reason = "Can not enter a null monitor.";
-      }
-
-      result = 0;
-      break;
-
-    case Bytecodes::_monitorexit:
-      if (reason != NULL) {
-        *reason = "Can not exit a null monitor.";
-      }
-
-      result = 0;
-      break;
-
-    case Bytecodes::_putfield:
-      {
+      return 2;
+    case Bytecodes::_lastore:
+    case Bytecodes::_dastore:
+      return 3;
+    case Bytecodes::_putfield: {
         int cp_index = Bytes::get_native_u2(code_base + pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
         ConstantPool* cp = _method->constants();
         int name_and_type_index = cp->name_and_type_ref_index_at(cp_index);
         int type_index = cp->signature_ref_index_at(name_and_type_index);
         Symbol* signature = cp->symbol_at(type_index);
-
-        if (reason != NULL) {
-          stringStream ss;
-          ss.print("Can not write field '%s'.",
-                   MethodBytecodePrinter::get_field_name(_method, cp_index));
-          *reason = ss.as_string();
-        }
-
-        result = type2size[char2type((char) signature->char_at(0))];
+        return type2size[char2type((char) signature->char_at(0))];
       }
-
-      break;
-
     case Bytecodes::_invokevirtual:
     case Bytecodes::_invokespecial:
     case Bytecodes::_invokeinterface:
@@ -1310,26 +897,332 @@
         // (which is true in Java). This is mainly used to avoid generating wrong
         // messages for NullPointerExceptions created explicitly by new in Java code.
         if (name != vmSymbols::object_initializer_name()) {
-          if (reason != NULL) {
-            stringStream ss;
-            ss.print("Can not invoke method '%s'.",
-                     MethodBytecodePrinter::get_method_name(_method, cp_index));
-            *reason = ss.as_string();
-          }
-
-          result = ArgumentSizeComputer(signature).size();
-        }
-        else {
-          result = -2;
+          return ArgumentSizeComputer(signature).size();
+        } else {
+          return -2;
         }
       }
 
-      break;
-
     default:
       break;
   }
 
-  return result;
+  return -1;
+}
+
+const int TrackingStackCreator::_max_cause_detail = 5;
+
+void TrackingStackCreator::TrackingStackCreator::print_NPE_cause(outputStream *os, int bci, int slot) {
+  if (print_NPE_cause0(os, bci, slot, _max_cause_detail, "'")) {
+    os->print("' is null. ");
+  }
 }
 
+/* Recursively print what was null.
+ *
+ * Go the the bytecode that pushed slot 'slot' on the operant stack
+ * at bytecode 'bci'. Compute a message for that bytecode. If
+ * necessary (array, field), recur further.
+ * At most do max_detail recursions.
+ *
+ * Returns true if something was printed.
+ */
+bool TrackingStackCreator::TrackingStackCreator::print_NPE_cause0(outputStream *os, int bci, int slot,
+                                                                  int max_detail, const char *prefix) {
+  assert(bci >= 0, "BCI too low");
+  assert(bci < get_size(), "BCI to large");
+
+  if (max_detail <= 0) {
+    return false;
+  }
+
+  if (_stacks->at(bci) == NULL) {
+    return false;
+  }
+
+  TrackingStack* stack = _stacks->at(bci);
+  assert(slot >= 0, "Slot nr. too low");
+  assert(slot < stack->get_size(), "Slot nr. too large");
+
+  TrackingStackEntry entry = stack->get_entry(slot);
+
+  if (!entry.has_bci()) {
+    return false;
+  }
+
+  // Get the bytecode.
+  int source_bci = entry.get_bci();
+  address code_base = _method->constMethod()->code_base();
+  Bytecodes::Code code = Bytecodes::java_code_at(_method, code_base + source_bci);
+  bool is_wide = false;
+  int pos = source_bci + 1;
+
+  if (code == Bytecodes::_wide) {
+    is_wide = true;
+    code = Bytecodes::java_code_at(_method, code_base + source_bci + 1);
+    pos += 1;
+  }
+
+  if (max_detail == _max_cause_detail &&
+      prefix != NULL &&
+      code != Bytecodes::_invokevirtual &&
+      code != Bytecodes::_invokespecial &&
+      code != Bytecodes::_invokestatic &&
+      code != Bytecodes::_invokeinterface) {
+    os->print("%s", prefix);
+  }
+
+  switch (code) {
+    case Bytecodes::_iload_0:
+    //case Bytecodes::_lload_0: // ?
+    //case Bytecodes::_fload_0: // ?
+    //case Bytecodes::_dload_0: // ?
+    case Bytecodes::_aload_0:
+      print_local_var(os, source_bci, _method, 0);
+      return true;
+
+    case Bytecodes::_iload_1:
+    //case Bytecodes::_lload_1: // ?
+    //case Bytecodes::_fload_1: // ?
+    //case Bytecodes::_dload_1: // ?
+    case Bytecodes::_aload_1:
+      print_local_var(os, source_bci, _method, 1);
+      return true;
+
+    case Bytecodes::_iload_2:
+    //case Bytecodes::_lload_2: // ?
+    //case Bytecodes::_fload_2: // ?
+    //case Bytecodes::_dload_2: // ?
+    case Bytecodes::_aload_2:
+      print_local_var(os, source_bci, _method, 2);
+      return true;
+
+    case Bytecodes::_iload_3:
+    //case Bytecodes::_lload_3: // ?
+    //case Bytecodes::_fload_3: // ?
+    //case Bytecodes::_dload_3: // ?
+    case Bytecodes::_aload_3:
+      print_local_var(os, source_bci, _method, 3);
+      return true;
+
+    case Bytecodes::_iload:
+    //case Bytecodes::_lload: // ?
+    //case Bytecodes::_fload: // ?
+    //case Bytecodes::_dload: // ?
+    case Bytecodes::_aload: {
+      int index;
+
+      if (is_wide) {
+        index = Bytes::get_Java_u2(code_base + source_bci + 2);
+      } else {
+        index = *(uint8_t*) (code_base + source_bci + 1);
+      }
+
+      print_local_var(os, source_bci, _method, index);
+      return true;
+    }
+
+    case Bytecodes::_aconst_null:
+      os->print("null");
+      return true;
+    case Bytecodes::_iconst_m1:
+      os->print("-1");
+      return true;
+    case Bytecodes::_iconst_0:
+      os->print("0");
+      return true;
+    case Bytecodes::_iconst_1:
+      os->print("1");
+      return true;
+    case Bytecodes::_iconst_2:
+      os->print("2");
+      return true;
+    case Bytecodes::_iconst_3:
+      os->print("3");
+      return true;
+    case Bytecodes::_iconst_4:
+      os->print("4");
+      return true;
+    case Bytecodes::_iconst_5:
+      os->print("5");
+      return true;
+      /*
+    case Bytecodes::_lconst_0: // ?
+      os->print("0L");
+      return true;
+    case Bytecodes::_lconst_1: // ?
+      os->print("1L");
+      return true;
+    case Bytecodes::_fconst_0: // ?
+      os->print("0.0f");
+      return true;
+    case Bytecodes::_fconst_1: // ?
+      os->print("1.0f");
+      return true;
+    case Bytecodes::_fconst_2: // ?
+      os->print("2.0f");
+      return true;
+    case Bytecodes::_dconst_0: // ?
+      os->print("0.0");
+      return true;
+    case Bytecodes::_dconst_1: // ?
+      os->print("1.0");
+      return true;
+      */
+    case Bytecodes::_bipush: {
+      jbyte con = *(jbyte*) (code_base + source_bci + 1);
+      os->print("%d", con);
+      return true;
+    }
+    case Bytecodes::_sipush: {
+      u2 con = Bytes::get_Java_u2(code_base + source_bci + 1);
+      os->print("%d", con);
+      return true;
+    }
+   case Bytecodes::_iaload:
+      //case Bytecodes::_faload: // ?
+  case Bytecodes::_aaload: {
+    //case Bytecodes::_baload: // ?
+    //case Bytecodes::_caload: // ?
+    //case Bytecodes::_saload: // ?
+    //case Bytecodes::_laload: // ?
+    //case Bytecodes::_daload: { // ?
+
+      // Print the 'name' of the array. Go back to the bytecode that
+      // pushed the array reference on the operand stack.
+      if (!print_NPE_cause0(os, source_bci, 1, max_detail-1)) {
+        //  Returned false. Max recursion depth was reached. Print dummy.
+        os->print("<array>");
+      }
+      os->print("[");
+      // Print the index expression. Go back to the bytecode that
+      // pushed the index on the operand stack.
+      // Don't decrement maxdetail so we get a value here and only 
+      // cancel out on the dereference.
+      if (!print_NPE_cause0(os, source_bci, 0, max_detail)) {
+        // Returned false. We don't print complex array index expressions. Print placeholder.
+        os->print("...");
+      }
+      os->print("]");
+      return true;
+    }
+
+    case Bytecodes::_getstatic: {
+      int cp_index = Bytes::get_native_u2(code_base + pos) + ConstantPool::CPCACHE_INDEX_TAG;
+      os->print("static ");
+      print_field_and_class(os, _method, cp_index);
+      return true;
+    }
+
+    case Bytecodes::_getfield: {
+      // Print the sender. Go back to the bytecode that
+      // pushed the sender on the operand stack.
+      if (print_NPE_cause0(os, source_bci, 0, max_detail - 1)) {
+        os->print(".");
+      }
+      int cp_index = Bytes::get_native_u2(code_base + pos) + ConstantPool::CPCACHE_INDEX_TAG;
+      os->print("%s", get_field_name(_method, cp_index));
+      return true;
+    }
+
+    case Bytecodes::_invokevirtual:
+    case Bytecodes::_invokespecial:
+    case Bytecodes::_invokestatic:
+    case Bytecodes::_invokeinterface: {
+      int cp_index = Bytes::get_native_u2(code_base + pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
+      if (max_detail == _max_cause_detail) {
+        os->print("The return value of '");
+      }
+      print_method_name(os, _method, cp_index);
+      return true;
+    }
+
+    default: break;
+  }
+  return false;
+}
+
+void TrackingStackCreator::print_NPE_failedAction(outputStream *os, int bci) {
+  // If this NPE was created via reflection, we have no real NPE.
+  assert(_method->method_holder() != SystemDictionary::reflect_NativeConstructorAccessorImpl_klass(),
+         "We should have checked for reflection in get_NPE_null_slot().");
+
+  // Get the bytecode.
+  address code_base = _method->constMethod()->code_base();
+  Bytecodes::Code code = Bytecodes::java_code_at(_method, code_base + bci);
+  int pos = bci + 1;
+  if (code == Bytecodes::_wide) {
+    code = Bytecodes::java_code_at(_method, code_base + bci + 1);
+    pos += 1;
+  }
+
+  switch (code) {
+    case Bytecodes::_iaload:
+      os->print("Can not load from null int array."); break;
+    case Bytecodes::_faload:
+      os->print("Can not load from null float array."); break;
+    case Bytecodes::_aaload:
+      os->print("Can not load from null object array."); break;
+    case Bytecodes::_baload:
+      os->print("Can not load from null byte/boolean array."); break;
+    case Bytecodes::_caload:
+      os->print("Can not load from null char array."); break;
+    case Bytecodes::_saload:
+      os->print("Can not load from null short array."); break;
+    case Bytecodes::_laload:
+      os->print("Can not load from null long array."); break;
+    case Bytecodes::_daload:
+      os->print("Can not load from null double array."); break;
+
+    case Bytecodes::_iastore:
+      os->print("Can not store to null int array."); break;
+    case Bytecodes::_fastore:
+      os->print("Can not store to null float array."); break;
+    case Bytecodes::_aastore:
+      os->print("Can not store to null object array."); break;
+    case Bytecodes::_bastore:
+      os->print("Can not store to null byte/boolean array."); break;
+    case Bytecodes::_castore:
+      os->print("Can not store to null char array."); break;
+    case Bytecodes::_sastore:
+      os->print("Can not store to null short array."); break;
+    case Bytecodes::_lastore:
+      os->print("Can not store to null long array."); break;
+    case Bytecodes::_dastore:
+      os->print("Can not store to null double array."); break;
+
+    case Bytecodes::_arraylength:
+      os->print("Can not read the array length."); break;
+    case Bytecodes::_athrow:
+      os->print("Can not throw a null exception object."); break;
+    case Bytecodes::_monitorenter:
+      os->print("Can not enter a null monitor."); break;
+    case Bytecodes::_monitorexit:
+      os->print("Can not exit a null monitor."); break;
+    case Bytecodes::_getfield: {
+        int cp_index = Bytes::get_native_u2(code_base + pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
+        ConstantPool* cp = _method->constants();
+        int name_and_type_index = cp->name_and_type_ref_index_at(cp_index);
+        int name_index = cp->name_ref_index_at(name_and_type_index);
+        Symbol* name = cp->symbol_at(name_index);
+        os->print("Can not read field '%s'.", name->as_C_string());
+      } break;
+    case Bytecodes::_putfield: {
+        int cp_index = Bytes::get_native_u2(code_base + pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
+        os->print("Can not write field '%s'.", get_field_name(_method, cp_index));
+      } break;
+    case Bytecodes::_invokevirtual:
+    case Bytecodes::_invokespecial:
+    case Bytecodes::_invokeinterface: {
+        int cp_index = Bytes::get_native_u2(code_base+ pos) DEBUG_ONLY(+ ConstantPool::CPCACHE_INDEX_TAG);
+        os->print("Can not invoke method '");
+        print_method_name(os, _method, cp_index);
+        os->print("'.");
+      } break;
+
+    default:
+      assert(0, "We should have checked this bytecode in get_NPE_null_slot().");
+      break;
+  }
+}
+
--- a/src/hotspot/share/interpreter/bytecodeUtils.hpp	Wed Apr 10 08:15:45 2019 +0200
+++ b/src/hotspot/share/interpreter/bytecodeUtils.hpp	Wed Apr 10 08:26:23 2019 +0200
@@ -23,37 +23,13 @@
  *
  */
 
-#ifndef SHARE_CLASSFILE_BYTECODEUTILS_HPP
-#define SHARE_CLASSFILE_BYTECODEUTILS_HPP
+#ifndef SHARE_INTERPRETER_BYTECODEUTILS_HPP
+#define SHARE_INTERPRETER_BYTECODEUTILS_HPP
 
 #include "memory/allocation.hpp"
 #include "oops/method.hpp"
 #include "utilities/growableArray.hpp"
-
-
-// A class which can be used to print out the bytecode
-// of a method.
-// NOTE: The method must already be rewritten.
-class MethodBytecodePrinter : public AllStatic {
- public:
-
-  // Returns the external (using '.') name of the class at the given cp index in an
-  // area allocated string.
-  static char const* get_klass_name(Method* method, int cp_index);
-
-  // Returns the name of the method(including signature, but without
-  // the return type) at the given cp index in a resource area
-  // allocated string.
-  static char const* get_method_name(Method* method, int cp_index);
-
-  // Returns the name of the field at the given cp index in
-  // a resource area allocated string.
-  static char const *get_field_name(Method* method, int cp_index);
-
-  // Returns the name and class of the field at the given cp index in
-  // a resource area allocated string.
-  static char const* get_field_and_class(Method* method, int cp_index);
-};
+#include "utilities/globalDefinitions.hpp"
 
 class TrackingStack;
 class TrackingStackCreator;
@@ -140,56 +116,9 @@
   TrackingStackEntry get_entry(int slot);
 };
 
-// Defines a source of a slot of the operand stack.
-class TrackingStackSource {
-
- public:
-
-  enum Type {
-    // If the value was loaded from a local variable.
-    LOCAL_VAR,
-
-    // If the value was returned from a method.
-    METHOD,
-
-    // If the value was loaded from an array.
-    ARRAY_ELEM,
-
-    // If the value was loaded from a field.
-    FIELD_ELEM,
-
-    // If the value was from a constant.
-    CONSTANT,
-
-    // If the source is invalid.
-    INVALID
-  };
-
- private:
-
-  const char *_reason;
-
-  Type _type;
-  int _bci;
-
- public:
-
-  TrackingStackSource(Type type, int bci, const char * reason) : _reason(reason), _type(type), _bci(bci) { }
-
-  // Returns the type.
-  Type get_type() const {
-    return _type;
-  }
-
-  // Returns a human readable string describing the source.
-  char const* as_string() const {
-    return _reason;
-  }
-};
-
 // Analyses the bytecodes of a method and tries to create a tracking
 // stack for each bci. The tracking stack holds the bci and type of
-// the objec on the stack. The bci (if valid) holds the bci of the
+// the object on the stack. The bci (if valid) holds the bci of the
 // instruction, which put the entry on the stack.
 class TrackingStackCreator {
 
@@ -213,6 +142,8 @@
   // If true, we have processed all bytecodes.
   bool _all_processed;
 
+  static const int _max_cause_detail;
+
   // Merges the stack the the given bci with the given stack. If there
   // is no stack at the bci, we just put the given stack there. This
   // method doesn't takes ownership of the stack.
@@ -222,6 +153,8 @@
   // the size of the instruction.
   int do_instruction(int bci);
 
+  bool print_NPE_cause0(outputStream *os, int bci, int slot, int max_detail, const char *prefix = NULL);
+
  public:
 
   // Creates tracking stacks for the given method (the method must be
@@ -236,22 +169,21 @@
   // Returns the number of stacks (this is the size of the method).
   int get_size() { return _stacks->length() - 1; }
 
-  // Returns the source of the value in the given slot at the given bci.
-  // The TOS has the slot number 0, that below 1 and so on. You have to
-  // delete the returned object via 'delete'. 'max_detail' is the number
-  // of levels for which we include sources recursively (e.g. for a source
-  // which was from an array and the array was loaded from field of an
-  // object which ...). The larger the value, the more detailed the source.
-  TrackingStackSource get_source(int bci, int slot, int max_detail);
-
   // Assuming that a NullPointerException was thrown at the given bci,
   // we return the nr of the slot holding the null reference. If this
   // NPE is created by hand, we return -2 as the slot. If there
-  // cannot be a NullPointerException at the bci, -1 is returned. If
-  // 'reason' is != NULL, a description is stored, which is allocated
-  // statically or in the resource area.
-  int get_null_pointer_slot(int bci, char const** reason);
+  // cannot be a NullPointerException at the bci, -1 is returned.
+  int get_NPE_null_slot(int bci);
 
+  // Prints a java-like expression for the bytecode that pushed
+  // the value to the given slot being live at the given bci.
+  // It constructs the expression recuring backwards over the
+  // bytecode.
+  // The TOS has the slot number 0, that below 1 and so on.
+  void print_NPE_cause(outputStream *os, int bci, int slot);
+
+  // Prints a string describing the failed action.
+  void print_NPE_failedAction(outputStream *os, int bci);
 };
 
-#endif // SHARE_CLASSFILE_BYTECODEUTILS_HPP
+#endif // SHARE_INTERPRETER_BYTECODEUTILS_HPP
--- a/src/hotspot/share/prims/jvm.cpp	Wed Apr 10 08:15:45 2019 +0200
+++ b/src/hotspot/share/prims/jvm.cpp	Wed Apr 10 08:26:23 2019 +0200
@@ -556,31 +556,29 @@
   }
 
   ResourceMark rm(THREAD);
+
+  // Analyse the bytecodes.
   TrackingStackCreator stc(method, bci);
-  char const* reason;
-  int slot = stc.get_null_pointer_slot(bci, &reason);
+
+  // The slot of the operand stack that contains the null reference.
+  int slot = stc.get_NPE_null_slot(bci);
 
   // Build the message.
   stringStream ss;
   if (slot == -2) {
+    // We don't want to print a message.
     return NULL;
   } else if (slot == -1) {
-    ss.print("There cannot be a NullPointerException at bci %d of method %s",
-             bci, method->name_and_sig_as_C_string());
-  } else if (reason == NULL) {
-    ss.print("Cannot get the reason for the NullPointerException at bci %d of method %s",
-             bci, method->name_and_sig_as_C_string());
+    // We encoutered a bytecode that does not dereference a reference.
+    DEBUG_ONLY(ss.print("There cannot be a NullPointerException at bci %d of method %s",
+                        bci, method->external_name()));
+    NOT_DEBUG(return NULL);
   } else {
-    TrackingStackSource source = stc.get_source(bci, slot, 5);
-    if (source.get_type() != TrackingStackSource::INVALID) {
-      const char *msg = source.as_string();
-      if (strncmp("The return value of", msg, strlen("The return value of")) == 0) {
-        ss.print("%s is null. ", msg);
-      } else {
-        ss.print("'%s' is null. ", msg);
-      }
-    }
-    ss.print("%s", reason);
+    // Print a description of what is null.
+    stc.print_NPE_cause(&ss, bci, slot);
+    // Print string describing which action (bytecode) could not be
+    // perfromed because of the null reference.
+    stc.print_NPE_failedAction(&ss, bci);
   }
 
   oop result = java_lang_String::create_oop_from_str(ss.as_string(), CHECK_0);
--- a/test/hotspot/jtreg/runtime/exceptionMsgs/NullPointerException/NullPointerExceptionTest.java	Wed Apr 10 08:15:45 2019 +0200
+++ b/test/hotspot/jtreg/runtime/exceptionMsgs/NullPointerException/NullPointerExceptionTest.java	Wed Apr 10 08:26:23 2019 +0200
@@ -27,6 +27,8 @@
  * @summary Test extended NullPointerException message for class
  *   files generated without debugging information. The message lists
  *   detailed information about the entity that is null.
+ * @modules java.base/java.lang:open
+ *          java.base/jdk.internal.org.objectweb.asm
  * @library /test/lib
  * @compile NullPointerExceptionTest.java
  * @run main NullPointerExceptionTest
@@ -36,9 +38,11 @@
  * @summary Test extended NullPointerException message for
  *   classfiles generated with debug information. In this case the name
  *   of the variable containing the array is printed.
+ * @modules java.base/java.lang:open
+ *          java.base/jdk.internal.org.objectweb.asm
  * @library /test/lib
  * @compile -g NullPointerExceptionTest.java
- * @run main/othervm -XX:+WizardMode -DhasDebugInfo NullPointerExceptionTest
+ * @run main/othervm -XX:+WizardMode NullPointerExceptionTest hasDebugInfo
  */
 
 import java.io.ByteArrayInputStream;
@@ -49,10 +53,22 @@
 
 import jdk.test.lib.Asserts;
 
+import java.lang.reflect.*;
+import java.lang.invoke.MethodHandles.Lookup;
+import static java.lang.invoke.MethodHandles.*;
+import static java.lang.invoke.MethodHandles.Lookup.*;
+
+import jdk.internal.org.objectweb.asm.ClassWriter;
+import jdk.internal.org.objectweb.asm.MethodVisitor;
+import jdk.internal.org.objectweb.asm.Type;
+import jdk.internal.org.objectweb.asm.Label;
+import static jdk.internal.org.objectweb.asm.Opcodes.*;
+
 /**
  * Tests NullPointerExceptions
  */
 public class NullPointerExceptionTest {
+
     // Some fields used in the test.
     static Object nullStaticField;
     NullPointerExceptionTest nullInstanceField;
@@ -61,15 +77,9 @@
     DoubleArrayGen dag;
     ArrayList<String> names = new ArrayList<>();
     ArrayList<String> curr;
-    static boolean hasDebugInfo = true;
+    static boolean hasDebugInfo = false;
 
     static {
-        try {
-            hasDebugInfo = System.getProperty("hasDebugInfo") != null;
-        } catch (Throwable t) {
-            throw new RuntimeException(t);
-        }
-
         staticArray       = new int[1][][][];
         staticArray[0]    = new int[1][][];
         staticArray[0][0] = new int[1][];
@@ -80,58 +90,537 @@
         System.out.println();
         System.out.println(" source code: " + expression);
         System.out.println("  thrown msg: " + obtainedMsg);
-        //System.out.println("expected msg: " + expectedMsg);
-        //Asserts.assertEquals(obtainedMsg, expectedMsg);
+        if (obtainedMsg.equals(expectedMsg)) return;
+        System.out.println("expected msg: " + expectedMsg);
+        Asserts.assertEquals(obtainedMsg, expectedMsg);
     }
 
     public static void main(String[] args) throws Exception {
         NullPointerExceptionTest t = new NullPointerExceptionTest();
-        t.testPointerChasing();
-        t.testArrayChasing();
-        t.testMethodChasing();
-        t.testMixedChasing();
+        if (args.length > 0) {
+            hasDebugInfo = true;
+        }
+
+        // Test the message printed for the failed action.
+        t.testFailedAction();
+
+        // Test the method printed for the null entity.
+        t.testNullEntity();
+        
+        // Test that no message is printed for exceptions
+        // allocated explicitly.
+        t.testCreation();
+        
+        // Test that no message is printed for exceptions
+        // thrown in native methods.
+        t.testNative();
+
+        // Test that two calls to getMessage() return the same
+        // message.
+        // It is a design decision that it returns two different
+        // String objects.
         t.testSameMessage();
-        t.testCreationViaNew();
-        t.testCreationViaReflection();
-        t.testCreationViaSerialization();
-        t.testLoadedFromLocalVariable1();
-        t.testLoadedFromLocalVariable2();
-        t.testLoadedFromLocalVariable3();
-        t.testLoadedFromLocalVariable4();
-        t.testLoadedFromLocalVariable5();
-        t.testLoadedFromLocalVariable6();
-        t.testLoadedFromLocalVariable7();
-        t.testLoadedFromMethod1();
-        t.testLoadedFromMethod2();
-        t.testLoadedFromMethod3();
-        t.testLoadedFromMethod4();
-        t.testLoadedFromMethod5();
-        t.testLoadedFromMethod6();
-        t.testLoadedFromMethod7();
-        t.testLoadedFromStaticField1();
-        t.testLoadedFromStaticField2();
-        t.testLoadedFromStaticField3();
-        t.testLoadedFromStaticField4(0, 0);
-        t.testLoadedFromStaticField5();
-        t.testLoadedFromStaticField5a();
-        t.testLoadedFromStaticField5b();
-        t.testLoadedFromStaticField6();
-        t.testLoadedFromInstanceField1();
-        t.testLoadedFromInstanceField2();
-        t.testLoadedFromInstanceField3();
-        t.testLoadedFromInstanceField4();
-        t.testLoadedFromInstanceField5();
-        t.testLoadedFromInstanceField6();
-        t.testInNative();
-        t.testMissingLocalVariableTable();
-        t.testNullMessages();
+        
+        // Test serialization.
+        // It is a design decision that after serialization the
+        // the message is lost.
+        t.testSerialization();
+
+        // Test that messages are printed for code generated 
+        // on-the-fly.
+        t.testGeneratedCode();
+        
+
+        // Some more interesting complex messages.
+        t.testComplexMessages();
+    }
+
+    // Helper method to cause test case.
+    private double callWithTypes(String[][] dummy1, int[][][] dummy2, float dummy3, long dummy4, short dummy5, 
+                                 boolean dummy6, byte dummy7, double dummy8, char dummy9) {
+        return 0.0;
     }
 
+    public void testFailedAction() {
+        int[]     ia1 = null;
+        float[]   fa1 = null;
+        Object[]  oa1 = null;
+        boolean[] za1 = null;
+        byte[]    ba1 = null;
+        char[]    ca1 = null;
+        short[]   sa1 = null;
+        long[]    la1 = null;
+        double[]  da1 = null;
+
+        // iaload
+        try {
+            System.out.println(ia1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("ia1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'ia1'" : "'<local1>'") + " is null. " +
+                         "Can not load from null int array.");
+        }
+        // faload
+        try {
+            System.out.println(fa1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("fa1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'fa1'" : "'<local2>'") + " is null. " +
+                         "Can not load from null float array.");
+        }
+        // aaload
+        try {
+            System.out.println(oa1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("oa1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'oa1'" : "'<local3>'") + " is null. " +
+                         "Can not load from null object array.");
+        }
+        // baload (boolean)
+        try {
+            System.out.println(za1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("za1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'za1'" : "'<local4>'") + " is null. " +
+                         "Can not load from null byte/boolean array.");
+        }
+        // baload (byte)
+        try {
+            System.out.println(ba1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("ba1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'ba1'" : "'<local5>'") + " is null. " +
+                         "Can not load from null byte/boolean array.");
+        }
+        // caload
+        try {
+            System.out.println(ca1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("ca1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'ca1'" : "'<local6>'") + " is null. " +
+                         "Can not load from null char array.");
+        }
+        // saload
+        try {
+            System.out.println(sa1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("sa1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'sa1'" : "'<local7>'") + " is null. " +
+                         "Can not load from null short array.");
+        }
+        // laload
+        try {
+            System.out.println(la1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("la1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'la1'" : "'<local8>'") + " is null. " +
+                         "Can not load from null long array.");
+        }
+        // daload
+        try {
+            System.out.println(da1[0]);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("da1[0]", e.getMessage(),
+                         (hasDebugInfo ? "'da1'" : "'<local9>'") + " is null. " +
+                         "Can not load from null double array.");
+        }
+
+        // iastore
+        try {
+            System.out.println(ia1[0] = 0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("ia1[0] = 0", e.getMessage(),
+                         (hasDebugInfo ? "'ia1'" : "'<local1>'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // fastore
+        try {
+            System.out.println(fa1[0] = 0.7f);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("fa1[0] = false", e.getMessage(),
+                         (hasDebugInfo ? "'fa1'" : "'<local2>'") + " is null. " +
+                         "Can not store to null float array.");
+        }
+        // aastore
+        try {
+            System.out.println(oa1[0] = null);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("oa1[0] = null", e.getMessage(),
+                         (hasDebugInfo ? "'oa1'" : "'<local3>'") + " is null. " +
+                         "Can not store to null object array.");
+        }
+        // bastore (boolean)
+        try {
+            System.out.println(za1[0] = false);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("za1[0] = false", e.getMessage(),
+                         (hasDebugInfo ? "'za1'" : "'<local4>'") + " is null. " +
+                         "Can not store to null byte/boolean array.");
+        }
+        // bastore (byte)
+        try {
+            System.out.println(ba1[0] = 0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("ba1[0] = 0", e.getMessage(),
+                         (hasDebugInfo ? "'ba1'" : "'<local5>'") + " is null. " +
+                         "Can not store to null byte/boolean array.");
+        }
+        // castore
+        try {
+            System.out.println(ca1[0] = 0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("ca1[0] = 0", e.getMessage(),
+                         (hasDebugInfo ? "'ca1'" : "'<local6>'") + " is null. " +
+                         "Can not store to null char array.");
+        }
+        // sastore
+        try {
+            System.out.println(sa1[0] = 0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("sa1[0] = 0", e.getMessage(),
+                         (hasDebugInfo ? "'sa1'" : "'<local7>'") + " is null. " +
+                         "Can not store to null short array.");
+        }
+        // lastore
+        try {
+            System.out.println(la1[0] = 0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("la1[0] = 0", e.getMessage(),
+                         (hasDebugInfo ? "'la1'" : "'<local8>'") + " is null. " +
+                         "Can not store to null long array.");
+        }
+        // dastore
+        try {
+            System.out.println(da1[0] = 0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("da1[0] = 0", e.getMessage(),
+                         (hasDebugInfo ? "'da1'" : "'<local9>'") + " is null. " +
+                         "Can not store to null double array.");
+        }
+
+        // arraylength
+        try {
+            System.out.println(za1.length);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("za1.length", e.getMessage(),
+                         (hasDebugInfo ? "'za1'" : "'<local4>'") + " is null. " +
+                         "Can not read the array length.");
+        }
+        // athrow
+        try {
+            throw null;
+        } catch (NullPointerException e) {
+            checkMessage("throw null", e.getMessage(),
+                         "'null' is null. " +
+                         "Can not throw a null exception object.");
+        }
+        // monitorenter
+        try {
+            synchronized (nullInstanceField) {
+                // desired
+            }
+        } catch (NullPointerException e) {
+            checkMessage("synchronized (nullInstanceField)", e.getMessage(),
+                         "'this.nullInstanceField' is null. " +
+                         "Can not enter a null monitor.");
+        }
+        // monitorexit
+        // No test available
+
+        // getfield
+        try {
+            System.out.println(nullInstanceField.nullInstanceField);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("nullInstanceField.nullInstanceField", e.getMessage(),
+                         "'this.nullInstanceField' is null. " +
+                         "Can not read field 'nullInstanceField'.");
+        }
+        // putfield
+        try {
+            System.out.println(nullInstanceField.nullInstanceField = null);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("nullInstanceField.nullInstanceField = null", e.getMessage(),
+                         "'this.nullInstanceField' is null. " +
+                         "Can not write field 'nullInstanceField'.");
+        }
+        // invoke
+        try {
+            nullInstanceField.toString();
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("nullInstanceField.toString()", e.getMessage(),
+                         "'this.nullInstanceField' is null. " +
+                         "Can not invoke method 'java.lang.String java.lang.Object.toString()'.");
+        }
+        // Test parameter and return types
+        try {
+            Asserts.assertTrue(nullInstanceField.callWithTypes(null, null, 0.0f, 0L, (short)0, false, (byte)0, 0.0, 'x') == 0.0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("nullInstanceField.callWithTypes(null, null, 0.0f, 0L, (short)0, false, (byte)0, 0.0, 'x')", e.getMessage(),
+                         "'this.nullInstanceField' is null. " +
+                         "Can not invoke method 'double NullPointerExceptionTest.callWithTypes(java.lang.String[][], int[][][], float, long, short, boolean, byte, double, char)'.");
+        }
+    }
+
+    static void test_iload() {
+        int i0 = 0;
+        int i1 = 1;
+        int i2 = 2;
+        int i3 = 3;
+        int i4 = 4;
+        int i5 = 5;
+        
+        int[][] a = new int[6][];
+
+        // iload_0
+        try {
+            a[i0][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[i0][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[i0]'" : "'<local6>[<local0>]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iload_1
+        try {
+            a[i1][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[i1][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[i1]'" : "'<local6>[<local1>]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iload_2
+        try {
+            a[i2][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[i2][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[i2]'" : "'<local6>[<local2>]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iload_3
+        try {
+            a[i3][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[i3][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[i3]'" : "'<local6>[<local3>]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iload
+        try {
+            a[i5][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[i5][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[i5]'" : "'<local6>[<local5>]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+    }
+
+    // Other datatyes than int are not needed.
+    // If we implement l2d and similar bytecodes, we can print
+    // long expressions as array indexes. Then these here could
+    // be used.
+    static void test_lload() {
+        long l0 = 0L;
+        long l1 = 1L;
+        long l2 = 2L;
+        long l3 = 3L;
+        long l4 = 4L;
+        long l5 = 5L;
+        
+        int[][] a = new int[6][];
+
+        // lload_0
+        try {
+            a[(int)l0][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)l0][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local12>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // lload_1
+        try {
+            a[(int)l1][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)l1][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local12>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // lload_2
+        try {
+            a[(int)l2][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)l2][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local12>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // lload_3
+        try {
+            a[(int)l3][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)l3][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local12>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // lload
+        try {
+            a[(int)l5][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)l5][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local12>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }        
+    }
+
+    static void test_fload() {
+        float f0 = 0.0f;
+        float f1 = 1.0f;
+        float f2 = 2.0f;
+        float f3 = 3.0f;
+        float f4 = 4.0f;
+        float f5 = 5.0f;
+        
+        int[][] a = new int[6][];
+
+        // fload_0
+        try {
+            a[(int)f0][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)f0][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local6>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // fload_1
+        try {
+            a[(int)f1][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)f1][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local6>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // fload_2
+        try {
+            a[(int)f2][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)f2][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local6>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // fload_3
+        try {
+            a[(int)f3][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)f3][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local6>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // fload
+        try {
+            a[(int)f5][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)f5][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[...]'" : "'<local6>[...]'") + " is null. " +
+                         "Can not store to null int array.");
+        }        
+    }
+
+    static void test_aload() {
+        F f0 = null;
+        F f1 = null;
+        F f2 = null;
+        F f3 = null;
+        F f4 = null;
+        F f5 = null;
+
+        // aload_0
+        try {
+            f0.i = 33;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("f0.i", e.getMessage(),
+                         (hasDebugInfo ? "'f0'" : "'<local0>'") + " is null. " +
+                         "Can not write field 'i'.");
+        }
+        // aload_1
+        try {
+            f1.i = 33;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("f1.i", e.getMessage(),
+                         (hasDebugInfo ? "'f1'" : "'<local1>'") + " is null. " +
+                         "Can not write field 'i'.");
+        }
+        // aload_2
+        try {
+            f2.i = 33;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("f2.i", e.getMessage(),
+                         (hasDebugInfo ? "'f2'" : "'<local2>'") + " is null. " +
+                         "Can not write field 'i'.");
+        }
+        // aload_3
+        try {
+            f3.i = 33;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("f3.i", e.getMessage(),
+                         (hasDebugInfo ? "'f3'" : "'<local3>'") + " is null. " +
+                         "Can not write field 'i'.");
+        }
+        // aload
+        try {
+            f5.i = 33;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("f5.i", e.getMessage(),
+                         (hasDebugInfo ? "'f5'" : "'<local5>'") + " is null. " +
+                         "Can not write field 'i'.");
+        } 
+    }
+
+    // Helper class for test cases.
     class A {
         public B to_b;
         public B getB() { return to_b; }
     }
 
+    // Helper class for test cases.
     class B {
         public C to_c;
         public B to_b;
@@ -139,16 +628,83 @@
         public B getBfromB() { return to_b; }
     }
 
+    // Helper class for test cases.
     class C {
         public D to_d;
         public D getD() { return to_d; }
     }
 
+    // Helper class for test cases.
     class D {
         public int num;
         public int[][] ar;
     }
 
+
+    public void testArrayChasing() {
+        int[][][][][][] a = null;
+        try {
+            a[0][0][0][0][0][0] = 99;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("int[0][0][0][0][0] = 99 // a is null", e.getMessage(),
+                         (hasDebugInfo ? "'a'" : "'<local1>'") + " is null. " +
+                         "Can not load from null object array.");
+        }
+        a = new int[1][][][][][];
+        try {
+            a[0][0][0][0][0][0] = 99;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("int[0][0][0][0][0] = 99 // a[0] is null", e.getMessage(),
+                         (hasDebugInfo ? "'a[0]'" : "'<local1>[0]'") + " is null. " +
+                         "Can not load from null object array.");
+        }
+        a[0] = new int[1][][][][];
+        try {
+            a[0][0][0][0][0][0] = 99;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("int[0][0][0][0][0] = 99 // a[0][0] is null", e.getMessage(),
+                         (hasDebugInfo ? "'a[0][0]'" : "'<local1>[0][0]'") + " is null. " +
+                         "Can not load from null object array.");
+        }
+        a[0][0] = new int[1][][][];
+        try {
+            a[0][0][0][0][0][0] = 99;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("int[0][0][0][0][0] = 99 // a[0][0][0] is null", e.getMessage(),
+                         (hasDebugInfo ? "'a[0][0][0]'" : "'<local1>[0][0][0]'") + " is null. " +
+                         "Can not load from null object array.");
+        }
+        a[0][0][0] = new int[1][][];
+        try {
+            a[0][0][0][0][0][0] = 99;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("int[0][0][0][0][0] = 99 // a[0][0][0][0] is null", e.getMessage(),
+                         (hasDebugInfo ? "'a[0][0][0][0]'" : "'<local1>[0][0][0][0]'") + " is null. " +
+                         "Can not load from null object array.");
+        }
+        a[0][0][0][0] = new int[1][];
+        // Reaching max recursion depth. Prints <array>.
+        try {
+            a[0][0][0][0][0][0] = 99;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("int[0][0][0][0][0] = 99 // a[0][0][0][0][0] is null", e.getMessage(),
+                         "'<array>[0][0][0][0][0]' is null. " +
+                         "Can not store to null int array.");
+        }
+        a[0][0][0][0][0] = new int[1];
+        try {
+            a[0][0][0][0][0][0] = 99;
+        } catch (NullPointerException e) {
+            Asserts.fail();
+        }
+    }
+
     public void testPointerChasing() {
         A a = null;
         try {
@@ -156,8 +712,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.to_b.to_c.to_d.num = 99 // a is null", e.getMessage(),
-                         "while trying to read the field 'to_b' of a null object loaded from " +
-                         (hasDebugInfo ? "local variable 'a'" : "a local variable at slot 1"));
+                         (hasDebugInfo ? "'a'" : "'<local1>'") + " is null. " +
+                         "Can not read field 'to_b'.");
         }
         a = new A();
         try {
@@ -165,8 +721,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.to_b.to_c.to_d.num = 99 // a.to_b is null", e.getMessage(),
-                         "while trying to read the field 'to_c' of a null object loaded from field 'NullPointerExceptionTest$A.to_b' of an object loaded from " +
-                         (hasDebugInfo ? "local variable 'a'" : "a local variable at slot 1"));
+                         (hasDebugInfo ? "'a.to_b'" : "'<local1>.to_b'") + " is null. " +
+                         "Can not read field 'to_c'.");
         }
         a.to_b = new B();
         try {
@@ -174,7 +730,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.to_b.to_c.to_d.num = 99 // a.to_b.to_c is null", e.getMessage(),
-                         "while trying to read the field 'to_d' of a null object loaded from field 'NullPointerExceptionTest$B.to_c' of an object loaded from field 'NullPointerExceptionTest$A.to_b' of an object");
+                         (hasDebugInfo ? "'a.to_b.to_c'" : "'<local1>.to_b.to_c'") + " is null. " +
+                         "Can not read field 'to_d'.");
         }
         a.to_b.to_c = new C();
         try {
@@ -182,59 +739,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.to_b.to_c.to_d.num = 99 // a.to_b.to_c.to_d is null", e.getMessage(),
-                         "while trying to write the field 'NullPointerExceptionTest$D.num' of a null object loaded from field 'NullPointerExceptionTest$C.to_d' of an object loaded from field 'NullPointerExceptionTest$B.to_c' of an object");
-        }
-    }
-
-    public void testArrayChasing() {
-        int[][][][][] a = null;
-        try {
-            a[0][0][0][0][0] = 99;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("int[0][0][0][0][0] = 99 // a is null", e.getMessage(),
-                         "while trying to load from a null object array loaded from " +
-                         (hasDebugInfo ? "local variable 'a'" : "a local variable at slot 1"));
-        }
-        a = new int[1][][][][];
-        try {
-            a[0][0][0][0][0] = 99;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("int[0][0][0][0][0] = 99 // a[0] is null", e.getMessage(),
-                         "while trying to load from a null object array loaded from an array (which itself was loaded from " +
-                         (hasDebugInfo ? "local variable 'a'" : "a local variable at slot 1") +
-                         ") with an index loaded from a constant");
-        }
-        a[0] = new int[1][][][];
-        try {
-            a[0][0][0][0][0] = 99;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("int[0][0][0][0][0] = 99 // a[0][0] is null", e.getMessage(),
-                         "while trying to load from a null object array loaded from an array (which itself was loaded from an array) with an index loaded from a constant");
-        }
-        a[0][0] = new int[1][][];
-        try {
-            a[0][0][0][0][0] = 99;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("int[0][0][0][0][0] = 99 // a[0][0][0] is null", e.getMessage(),
-                         "while trying to load from a null object array loaded from an array (which itself was loaded from an array) with an index loaded from a constant");
-        }
-        a[0][0][0] = new int[1][];
-        try {
-            a[0][0][0][0][0] = 99;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("int[0][0][0][0][0] = 99 // a[0][0][0][0] is null", e.getMessage(),
-                         "while trying to store to a null int array loaded from an array (which itself was loaded from an array) with an index loaded from a constant");
-        }
-        a[0][0][0][0] = new int[1];
-        try {
-            a[0][0][0][0][0] = 99;
-        } catch (NullPointerException e) {
-            Asserts.fail();
+                         (hasDebugInfo ? "'a.to_b.to_c.to_d'" : "'<local1>.to_b.to_c.to_d'") + " is null. " +
+                         "Can not write field 'num'.");
         }
     }
 
@@ -245,8 +751,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().num = 99 // a is null", e.getMessage(),
-                         "while trying to invoke the method 'NullPointerExceptionTest$A.getB()LNullPointerExceptionTest$B;' on a null reference loaded from " +
-                         (hasDebugInfo ? "local variable 'a'" : "a local variable at slot 1"));
+                         (hasDebugInfo ? "'a" : "'<local1>") + "' is null. " +
+                         "Can not invoke method 'NullPointerExceptionTest$B NullPointerExceptionTest$A.getB()'.");
         }
         a = new A();
         try {
@@ -254,7 +760,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().num = 99 // a.getB() is null", e.getMessage(),
-                         "while trying to invoke the method 'NullPointerExceptionTest$B.getBfromB()LNullPointerExceptionTest$B;' on a null reference returned from 'NullPointerExceptionTest$A.getB()LNullPointerExceptionTest$B;'");
+                         "The return value of 'NullPointerExceptionTest$B NullPointerExceptionTest$A.getB()' is null. " +
+                         "Can not invoke method 'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB()'.");
         }
         a.to_b = new B();
         try {
@@ -262,7 +769,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().num = 99 // a.getB().getBfromB() is null", e.getMessage(),
-                         "while trying to invoke the method 'NullPointerExceptionTest$B.getC()LNullPointerExceptionTest$C;' on a null reference returned from 'NullPointerExceptionTest$B.getBfromB()LNullPointerExceptionTest$B;'");
+                         "The return value of 'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB()' is null. " +
+                         "Can not invoke method 'NullPointerExceptionTest$C NullPointerExceptionTest$B.getC()'.");
         }
         a.to_b.to_b = new B();
         try {
@@ -270,7 +778,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().num = 99 // a.getB().getBfromB().getC() is null", e.getMessage(),
-                         "while trying to invoke the method 'NullPointerExceptionTest$C.getD()LNullPointerExceptionTest$D;' on a null reference returned from 'NullPointerExceptionTest$B.getC()LNullPointerExceptionTest$C;'");
+                         "The return value of 'NullPointerExceptionTest$C NullPointerExceptionTest$B.getC()' is null. " +
+                         "Can not invoke method 'NullPointerExceptionTest$D NullPointerExceptionTest$C.getD()'.");
         }
         a.to_b.to_b.to_c = new C();
         try {
@@ -278,7 +787,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().num = 99 // a.getB().getBfromB().getC().getD() is null", e.getMessage(),
-                         "while trying to write the field 'NullPointerExceptionTest$D.num' of a null object returned from 'NullPointerExceptionTest$C.getD()LNullPointerExceptionTest$D;'");
+                         "The return value of 'NullPointerExceptionTest$D NullPointerExceptionTest$C.getD()' is null. " +
+                         "Can not write field 'num'.");
         }
     }
 
@@ -289,8 +799,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a is null", e.getMessage(),
-                         "while trying to invoke the method 'NullPointerExceptionTest$A.getB()LNullPointerExceptionTest$B;' on a null reference loaded from " +
-                         (hasDebugInfo ? "local variable 'a'" : "a local variable at slot 1"));
+                         (hasDebugInfo ? "'a'" : "'<local1>'") + " is null. " +
+                         "Can not invoke method 'NullPointerExceptionTest$B NullPointerExceptionTest$A.getB()'.");
         }
         a = new A();
         try {
@@ -298,7 +808,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB() is null", e.getMessage(),
-                         "while trying to invoke the method 'NullPointerExceptionTest$B.getBfromB()LNullPointerExceptionTest$B;' on a null reference returned from 'NullPointerExceptionTest$A.getB()LNullPointerExceptionTest$B;'");
+                         "The return value of 'NullPointerExceptionTest$B NullPointerExceptionTest$A.getB()' is null. " +
+                         "Can not invoke method 'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB()'.");
         }
         a.to_b = new B();
         try {
@@ -306,7 +817,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB() is null", e.getMessage(),
-                         "while trying to read the field 'to_c' of a null object returned from 'NullPointerExceptionTest$B.getBfromB()LNullPointerExceptionTest$B;'");
+                         "The return value of 'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB()' is null. " +
+                         "Can not read field 'to_c'.");
         }
         a.to_b.to_b = new B();
         try {
@@ -314,7 +826,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c is null", e.getMessage(),
-                         "while trying to read the field 'to_d' of a null object loaded from field 'NullPointerExceptionTest$B.to_c' of an object returned from 'NullPointerExceptionTest$B.getBfromB()LNullPointerExceptionTest$B;'");
+                         "'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB().to_c' is null. " +
+                         "Can not read field 'to_d'.");
         }
         a.to_b.to_b.to_c = new C();
         try {
@@ -322,7 +835,8 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c.to_d is null", e.getMessage(),
-                         "while trying to read the field 'ar' of a null object loaded from field 'NullPointerExceptionTest$C.to_d' of an object loaded from field 'NullPointerExceptionTest$B.to_c' of an object");
+                         "'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB().to_c.to_d' is null. " +
+                         "Can not read field 'ar'.");
         }
         a.to_b.to_b.to_c.to_d = new D();
         try {
@@ -330,14 +844,16 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c.to_d.ar is null", e.getMessage(),
-                         "while trying to load from a null object array loaded from field 'NullPointerExceptionTest$D.ar' of an object loaded from field 'NullPointerExceptionTest$C.to_d' of an object");
+                         "'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB().to_c.to_d.ar' is null. " +
+                         "Can not load from null object array.");
         }
         try {
             a.getB().getBfromB().getC().getD().ar[0][0] = 99;
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().ar[0][0] = 99; // a.getB().getBfromB().getC().getD().ar is null", e.getMessage(),
-                         "while trying to load from a null object array loaded from field 'NullPointerExceptionTest$D.ar' of an object returned from 'NullPointerExceptionTest$C.getD()LNullPointerExceptionTest$D;'");
+                         "'NullPointerExceptionTest$D NullPointerExceptionTest$C.getD().ar' is null. " +
+                         "Can not load from null object array.");
         }
         a.to_b.to_b.to_c.to_d.ar = new int[1][];
         try {
@@ -345,25 +861,255 @@
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().to_c.to_d.ar[0][0] = 99; // a.getB().getBfromB().to_c.to_d.ar[0] is null", e.getMessage(),
-                         "while trying to store to a null int array loaded from an array (which itself was loaded from field 'NullPointerExceptionTest$D.ar' of an object) with an index loaded from a constant");
+                         "'NullPointerExceptionTest$B NullPointerExceptionTest$B.getBfromB().to_c.to_d.ar[0]' is null. " +
+                         "Can not store to null int array.");
         }
         try {
             a.getB().getBfromB().getC().getD().ar[0][0] = 99;
             Asserts.fail();
         } catch (NullPointerException e) {
             checkMessage("a.getB().getBfromB().getC().getD().ar[0][0] = 99; // a.getB().getBfromB().getC().getD().ar[0] is null", e.getMessage(),
-                         "while trying to store to a null int array loaded from an array (which itself was loaded from field 'NullPointerExceptionTest$D.ar' of an object) with an index loaded from a constant");
+                         "'NullPointerExceptionTest$D NullPointerExceptionTest$C.getD().ar[0]' is null. " +
+                         "Can not store to null int array.");
+        }
+    }
+
+    // Helper method to cause test case.
+    private Object returnNull(String[][] dummy1, int[][][] dummy2, float dummy3) {
+        return null;
+    }
+
+    // Helper method to cause test case.
+    private NullPointerExceptionTest returnMeAsNull(Throwable dummy1, int dummy2, char dummy3) {
+        return null;
+    }
+
+    // Helper interface for test cases.
+    static interface DoubleArrayGen {
+        public double[] getArray();
+    }
+
+    // Helper class for test cases.
+    static class DoubleArrayGenImpl implements DoubleArrayGen {
+        @Override
+        public double[] getArray() {
+            return null;
+        }
+    }
+
+    // Helper class for test cases.
+    static class NullPointerGenerator {
+        public static Object nullReturner(boolean dummy1) {
+            return null;
+        }
+
+        public Object returnMyNull(double dummy1, long dummy2, short dummy3) {
+            return null;
+        }
+    }
+
+    // Helper method to cause test case.
+    public void ImplTestLoadedFromMethod(DoubleArrayGen gen) {
+        try {
+            (gen.getArray())[0] = 1.0;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("(gen.getArray())[0]", e.getMessage(),
+                         "The return value of 'double[] NullPointerExceptionTest$DoubleArrayGen.getArray()' is null. Can not store to null double array.");
         }
     }
 
+    public void testNullEntity() {
+        int[][] a = new int[820][];
+        
+        test_iload();
+        test_lload();
+        test_fload();
+        // test_dload();
+        test_aload();
+        // aload_0: 'this'
+        try {
+            this.nullInstanceField.nullInstanceField = null;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("this.nullInstanceField.nullInstanceField = null", e.getMessage(),
+                         "'this.nullInstanceField' is null. Can not write field 'nullInstanceField'.");
+        }
+
+        // aconst_null
+        try {
+            throw null;
+        } catch (NullPointerException e) {
+            checkMessage("throw null", e.getMessage(),
+                         "'null' is null. Can not throw a null exception object.");
+        }        
+        // iconst_0
+        try {
+            a[0][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[0][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[0]'" : "'<local1>[0]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iconst_1
+        try {
+            a[1][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[1][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[1]'" : "'<local1>[1]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iconst_2
+        try {
+            a[2][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[2][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[2]'" : "'<local1>[2]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iconst_3
+        try {
+            a[3][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[3][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[3]'" : "'<local1>[3]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iconst_4
+        try {
+            a[4][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[4][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[4]'" : "'<local1>[4]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // iconst_5
+        try {
+            a[5][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[5][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[5]'" : "'<local1>[5]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // long --> iconst
+        try {
+            a[(int)0L][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[(int)0L][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[0]'" : "'<local1>[0]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // bipush
+        try {
+            a[139 /*0x77*/][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[139][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[139]'" : "'<local1>[139]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+        // sipush
+        try {
+            a[819 /*0x333*/][0] = 77;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("a[819][0]", e.getMessage(),
+                         (hasDebugInfo ? "'a[819]'" : "'<local1>[819]'") + " is null. " +
+                         "Can not store to null int array.");
+        }
+
+        // aaload, with recursive descend.
+        testArrayChasing();
+
+        // getstatic
+        try {
+            Asserts.assertTrue(((float[]) nullStaticField)[0] == 1.0f);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("((float[]) nullStaticField)[0]", e.getMessage(),
+                         "'static NullPointerExceptionTest.nullStaticField' is null. Can not load from null float array.");
+        }
+
+        // getfield, with recursive descend.
+        testPointerChasing();
+
+        // invokestatic
+        try {
+            Asserts.assertTrue(((char[]) NullPointerGenerator.nullReturner(false))[0] == 'A');
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("((char[]) NullPointerGenerator.nullReturner(false))[0]", e.getMessage(),
+                         "The return value of 'java.lang.Object NullPointerExceptionTest$NullPointerGenerator.nullReturner(boolean)' is null. Can not load from null char array.");
+        }
+        // invokevirtual
+        try {
+            Asserts.assertTrue(((char[]) (new NullPointerGenerator().returnMyNull(1, 1, (short) 1)))[0] == 'a');
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("((char[]) (new NullPointerGenerator().returnMyNull(1, 1, (short) 1)))[0]", e.getMessage(), 
+                         "The return value of 'java.lang.Object NullPointerExceptionTest$NullPointerGenerator.returnMyNull(double, long, short)' is null. Can not load from null char array.");
+        }
+        // Call with array arguments.
+        try {
+            Asserts.assertTrue(((double[]) returnNull(null, null, 1f))[0] == 1.0);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("((double[]) returnNull(null, null, 1f))[0] ", e.getMessage(),
+                         "The return value of 'java.lang.Object NullPointerExceptionTest.returnNull(java.lang.String[][], int[][][], float)' is null. Can not load from null double array.");
+        }
+        // invokeinterface
+        ImplTestLoadedFromMethod(new DoubleArrayGenImpl());
+        try {
+            returnMeAsNull(null, 1, 'A').dag = null;
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            checkMessage("returnMeAsNull(null, 1, 'A').dag = null", e.getMessage(),
+                         "The return value of 'NullPointerExceptionTest NullPointerExceptionTest.returnMeAsNull(java.lang.Throwable, int, char)' is null. Can not write field 'dag'.");
+        }
+        testMethodChasing();
+
+        // Mixed recursive descend.
+        testMixedChasing();
+
+    }
+
+
+    public void testCreation() throws Exception {
+        // If allocated with new, the message should not be generated.
+        Asserts.assertNull(new NullPointerException().getMessage());
+        String msg = new String("A pointless message.");
+        Asserts.assertTrue(new NullPointerException(msg).getMessage() == msg);
+        
+        // If created via reflection, the message should not be generated.
+        Exception ex = NullPointerException.class.getDeclaredConstructor().newInstance();
+        Asserts.assertNull(ex.getMessage());        
+    }
+
+    public void testNative() throws Exception {
+        // If NPE is thrown in a native method, the message should
+        // not be generated.
+        try {
+            Class.forName(null);
+            Asserts.fail();
+        } catch (NullPointerException e) {
+            Asserts.assertNull(e.getMessage());
+        }
+        
+    }
 
     // Test we get the same message calling npe.getMessage() twice.
     public void testSameMessage() throws Exception {
         Object null_o = null;
         String expectedMsg =
-            "while trying to invoke the method 'java.lang.Object.hashCode()I'" +
-            " on a null reference loaded from " +
-            (hasDebugInfo ? "local variable 'null_o'" : "a local variable at slot 1");
+            (hasDebugInfo ? "'null_o" : "'<local1>") + "' is null. " +
+            "Can not invoke method 'int java.lang.Object.hashCode()'.";
 
         try {
             null_o.hashCode();
@@ -374,30 +1120,13 @@
             String msg2 = npe.getMessage();
             Asserts.assertTrue(msg1.equals(msg2));
             // It was decided that getMessage should generate the
-            // message anew on every call, so this does not hold any more.
+            // message anew on every call, so this does not hold.
+            //Asserts.assertTrue(msg1 == msg2);
             Asserts.assertFalse(msg1 == msg2);
         }
     }
 
-    /**
-     *
-     */
-    public void testCreationViaNew() {
-        Asserts.assertNull(new NullPointerException().getMessage());
-    }
-
-    /**
-     * @throws Exception
-     */
-    public void testCreationViaReflection() throws Exception {
-        Exception ex = NullPointerException.class.getDeclaredConstructor().newInstance();
-        Asserts.assertNull(ex.getMessage());
-    }
-
-    /**
-     * @throws Exception
-     */
-    public void testCreationViaSerialization() throws Exception {
+    public void testSerialization() throws Exception {
         // NPE without message.
         Object o1 = new NullPointerException();
         ByteArrayOutputStream bos1 = new ByteArrayOutputStream();
@@ -429,9 +1158,9 @@
         } catch (NullPointerException npe3) {
             o3 = npe3;
             msg3 = npe3.getMessage();
-            checkMessage("null_o3.hashCode()", msg3, "while trying to invoke the method 'java.lang.Object.hashCode()I'" +
-                                 " on a null reference loaded from " +
-                                 (hasDebugInfo ? "local variable 'null_o3'" : "a local variable at slot 14"));
+            checkMessage("null_o3.hashCode()", msg3, 
+                         (hasDebugInfo ? "'null_o3'" : "'<local14>'") + " is null. " +
+                         "Can not invoke method 'int java.lang.Object.hashCode()'.");
         }
         ByteArrayOutputStream bos3 = new ByteArrayOutputStream();
         ObjectOutputStream oos3 = new ObjectOutputStream(bos3);
@@ -446,791 +1175,124 @@
         Asserts.assertEquals(ex3.getMessage(), null);
     }
 
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable1() {
-        Object o = null;
-
-        try {
-            o.hashCode();
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("o.hashCode()", e.getMessage(), "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " + (hasDebugInfo ? "local variable 'o'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable2() {
-        Exception[] myVariable = null;
-
-        try {
-            Asserts.assertNull(myVariable[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("myVariable[0]", e.getMessage(), "while trying to load from a null object array loaded from " + (hasDebugInfo ? "local variable 'myVariable'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable3() {
-        Exception[] myVariable = null;
-
-        try {
-            myVariable[0] = null;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("myVariable[0] = null", e.getMessage(), "while trying to store to a null object array loaded from " + (hasDebugInfo ? "local variable 'myVariable'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable4() {
-        Exception[] myVariable\u0096 = null;
-
-        try {
-            Asserts.assertTrue(myVariable\u0096.length == 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("myVariable\u0096.length", e.getMessage(), "while trying to get the length of a null array loaded from " + (hasDebugInfo ? "local variable 'myVariable'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     * @throws Exception
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable5() throws Exception {
-        Exception myException = null;
-
-        try {
-            throw myException;
-        } catch (NullPointerException e) {
-            checkMessage("throw myException", e.getMessage(), "while trying to throw a null exception object loaded from " + (hasDebugInfo ? "local variable 'myException'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable6() {
-        byte[] myVariable = null;
-        int my_index = 1;
-
-        try {
-            Asserts.assertTrue(myVariable[my_index] == 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("myVariable[my_index]", e.getMessage(), "while trying to load from a null byte (or boolean) array loaded from " + (hasDebugInfo ? "local variable 'myVariable'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromLocalVariable7() {
-        byte[] myVariable = null;
-
-        try {
-            myVariable[System.out.hashCode()] = (byte) 0;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("myVariable[System.out.hashCode()]", e.getMessage(), "while trying to store to a null byte (or boolean) array loaded from " + (hasDebugInfo ? "local variable 'myVariable'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromMethod1() {
-        try {
-            Asserts.assertTrue(((char[]) NullPointerGenerator.nullReturner(false))[0] == 'A');
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("((char[]) NullPointerGenerator.nullReturner(false))[0]", e.getMessage(), "while trying to load from a null char array returned from 'NullPointerExceptionTest$NullPointerGenerator.nullReturner(Z)Ljava/lang/Object;'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromMethod2() {
-        try {
-            Asserts.assertTrue(((char[]) (new NullPointerGenerator().returnMyNull(1, 1, (short) 1)))[0] == 'a');
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("((char[]) (new NullPointerGenerator().returnMyNull(1, 1, (short) 1)))[0]", e.getMessage(), "while trying to load from a null char array returned from 'NullPointerExceptionTest$NullPointerGenerator.returnMyNull(DJS)Ljava/lang/Object;'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromMethod3() {
-        try {
-            Asserts.assertTrue(((double[]) returnNull(null, null, 1f))[0] == 1.0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("((double[]) returnNull(null, null, 1f))[0] ", e.getMessage(), "while trying to load from a null double array returned from 'NullPointerExceptionTest.returnNull([[Ljava/lang/String;[[[IF)Ljava/lang/Object;'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromMethod4() {
-        ImplTestLoadedFromMethod4(new DoubleArrayGenImpl());
-    }
-
-    /**
-     * @param gen
-     */
-    public void ImplTestLoadedFromMethod4(DoubleArrayGen gen) {
-        try {
-            (gen.getArray())[0] = 1.0;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("(gen.getArray())[0]", e.getMessage(), "while trying to store to a null double array returned from 'NullPointerExceptionTest$DoubleArrayGen.getArray()[D'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromMethod5() {
-        try {
-            returnMeAsNull(null, 1, 'A').dag = null;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("returnMeAsNull(null, 1, 'A').dag = null", e.getMessage(), "while trying to write the field 'NullPointerExceptionTest.dag' of a null object returned from 'NullPointerExceptionTest.returnMeAsNull(Ljava/lang/Throwable;IC)LNullPointerExceptionTest;'");
-        }
-        /*
-        try {
-            returnMeAsNull(null, 1, 'A').dag.dag = null;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("returnMeAsNull(null, 1, 'A').dag.dag = null", e.getMessage(), "while trying to write the field 'NullPointerExceptionTest.dag' of a null object returned from 'NullPointerExceptionTest.returnMeAsNull(Ljava/lang/Throwable;IC)LNullPointerExceptionTest;'");
-        }
-        */
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromMethod6() {
-        short[] sa = null;
-
-        try {
-            Asserts.assertTrue(sa[0] == (short) 1);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("sa[0]", e.getMessage(), "while trying to load from a null short array loaded from " + (hasDebugInfo ? "local variable 'sa'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testLoadedFromMethod7() {
-        short[] sa = null;
-
-        try {
-            sa[0] = 1;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("sa[0] = 1", e.getMessage(), "while trying to store to a null short array loaded from " + (hasDebugInfo ? "local variable 'sa'" : "a local variable at slot 1"));
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromStaticField1() {
-        try {
-            Asserts.assertTrue(((float[]) nullStaticField)[0] == 1.0f);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("((float[]) nullStaticField)[0]", e.getMessage(), "while trying to load from a null float array loaded from static field 'NullPointerExceptionTest.nullStaticField'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromStaticField2() {
-        try {
-            ((float[]) nullStaticField)[0] = 1.0f;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("((float[]) nullStaticField)[0] = 1.0f", e.getMessage(), "while trying to store to a null float array loaded from static field 'NullPointerExceptionTest.nullStaticField'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromStaticField3() {
-        try {
-            Asserts.assertTrue(staticArray[0][0][0][0] == 1);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("staticArray[0][0][0][0] // staticArray[0][0][0] is null.", e.getMessage(), "while trying to load from a null int array loaded from an array (which itself was loaded from an array) with an index loaded from a constant");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromStaticField4(int myIdx, int pos) {
-        try {
-            staticArray[0][0][pos][myIdx] = 2;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage(" staticArray[0][0][pos][myIdx] = 2", e.getMessage(), "while trying to store to a null int array loaded from an array (which itself was loaded from an array) with an index loaded from " + (hasDebugInfo ? "local variable 'pos'" : "the parameter nr. 2 of the method"));
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromStaticField5() {
-        try {
-            Asserts.assertTrue(staticLongArray[0][0] == 1L);
-        } catch (NullPointerException e) {
-            checkMessage("staticLongArray[0][0]", e.getMessage(), "while trying to load from a null long array loaded from an array (which itself was loaded from static field 'NullPointerExceptionTest.staticLongArray') with an index loaded from a constant");
-        }
-    }
-
-    /**
-     * Test bipush for index.
-     */
-    public void testLoadedFromStaticField5a() {
-        try {
-            Asserts.assertTrue(staticLongArray[139 /*0x77*/][0] == 1L);
-        } catch (NullPointerException e) {
-            checkMessage("staticLongArray[139][0]", e.getMessage(), "while trying to load from a null long array loaded from an array (which itself was loaded from static field 'NullPointerExceptionTest.staticLongArray') with an index loaded from a constant");
-        }
-    }
-
-    /**
-     * Test sipush for index.
-     */
-    public void testLoadedFromStaticField5b() {
-        try {
-            Asserts.assertTrue(staticLongArray[819 /*0x333*/][0] == 1L);
-        } catch (NullPointerException e) {
-            checkMessage("staticLongArray[819][0]",  e.getMessage(), "while trying to load from a null long array loaded from an array (which itself was loaded from static field 'NullPointerExceptionTest.staticLongArray') with an index loaded from a constant");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromStaticField6() {
+    public void testComplexMessages() {
         try {
             staticLongArray[0][0] = 2L;
             Asserts.fail();
         } catch (NullPointerException e) {
-            checkMessage("staticLongArray[0][0] = 2L", e.getMessage(), "while trying to store to a null long array loaded from an array (which itself was loaded from static field 'NullPointerExceptionTest.staticLongArray') with an index loaded from a constant");
+            checkMessage("staticLongArray[0][0] = 2L", e.getMessage(),
+                         "'static NullPointerExceptionTest.staticLongArray[0]' is null. " +
+                         "Can not store to null long array.");
         }
-    }
 
-    /**
-     *
-     */
-    public void testLoadedFromInstanceField1() {
         try {
             Asserts.assertTrue(this.nullInstanceField.nullInstanceField == null);
             Asserts.fail();
         } catch (NullPointerException e) {
-            checkMessage("this.nullInstanceField.nullInstanceField", e.getMessage(), "while trying to read the field 'nullInstanceField' of a null object loaded from field 'NullPointerExceptionTest.nullInstanceField' of an object loaded from 'this'");
+            checkMessage("this.nullInstanceField.nullInstanceField", e.getMessage(),
+                         "'this.nullInstanceField' is null. " +
+                         "Can not read field 'nullInstanceField'.");
         }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromInstanceField2() {
-        try {
-            this.nullInstanceField.nullInstanceField = null;
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("this.nullInstanceField.nullInstanceField = null", e.getMessage(), "while trying to write the field 'NullPointerExceptionTest.nullInstanceField' of a null object loaded from field 'NullPointerExceptionTest.nullInstanceField' of an object loaded from 'this'");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromInstanceField3() {
-        NullPointerExceptionTest obj = this;
 
         try {
+            NullPointerExceptionTest obj = this;
             Asserts.assertNull(obj.dag.getArray().clone());
             Asserts.fail();
         } catch (NullPointerException e) {
-            checkMessage("obj.dag.getArray().clone()", e.getMessage(), "while trying to invoke the method 'NullPointerExceptionTest$DoubleArrayGen.getArray()[D' on a null reference loaded from field 'NullPointerExceptionTest.dag' of an object loaded from " + (hasDebugInfo ? "local variable 'obj'" : "a local variable at slot 1"));
+            checkMessage("obj.dag.getArray().clone()", e.getMessage(),
+                         (hasDebugInfo ? "'obj" : "'<local1>") + ".dag' is null. " +
+                         "Can not invoke method 'double[] NullPointerExceptionTest$DoubleArrayGen.getArray()'.");
         }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromInstanceField4() {
-        int indexes[] = new int[1];
-
-        NullPointerExceptionTest[] objs = new NullPointerExceptionTest[] {this};
-
         try {
+            int indexes[] = new int[1];
+            NullPointerExceptionTest[] objs = new NullPointerExceptionTest[] {this};
             Asserts.assertNull(objs[indexes[0]].nullInstanceField.returnNull(null, null, 1f));
             Asserts.fail();
         } catch (NullPointerException e) {
-            checkMessage("objs[indexes[0]].nullInstanceField.returnNull(null, null, 1f", e.getMessage(), "while trying to invoke the method 'NullPointerExceptionTest.returnNull([[Ljava/lang/String;[[[IF)Ljava/lang/Object;' on a null reference loaded from field 'NullPointerExceptionTest.nullInstanceField' of an object loaded from an array");
+            checkMessage("objs[indexes[0]].nullInstanceField.returnNull(null, null, 1f)", e.getMessage(),
+                         (hasDebugInfo ? "'objs[indexes" : "'<local2>[<local1>") + "[0]].nullInstanceField' is null. " +
+                         "Can not invoke method 'java.lang.Object NullPointerExceptionTest.returnNull(java.lang.String[][], int[][][], float)'.");
         }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromInstanceField5() {
-        int indexes[] = new int[1];
-
-        NullPointerExceptionTest[] objs = new NullPointerExceptionTest[] {this};
 
         try {
-            Asserts.assertNull(objs[indexes[0]].nullInstanceField.toString().toCharArray().clone());
-        } catch (NullPointerException e) {
-            checkMessage("objs[indexes[0]].nullInstanceField.toString().toCharArray().clone()", e.getMessage(), "while trying to invoke the method 'java.lang.Object.toString()Ljava/lang/String;' on a null reference loaded from field 'NullPointerExceptionTest.nullInstanceField' of an object loaded from an array");
-        }
-    }
-
-    /**
-     *
-     */
-    public void testLoadedFromInstanceField6() {
-        int indexes[] = new int[1];
-
-        NullPointerExceptionTest[][] objs =
-            new NullPointerExceptionTest[][] {new NullPointerExceptionTest[] {this}};
-
-        try {
-            // Check monitorenter only, since we cannot probe monitorexit from Java.
+            int indexes[] = new int[1];
+            NullPointerExceptionTest[][] objs =
+                new NullPointerExceptionTest[][] {new NullPointerExceptionTest[] {this}};
             synchronized (objs[indexes[0]][0].nullInstanceField) {
                 Asserts.fail();
             }
         } catch (NullPointerException e) {
-            checkMessage("synchronized (objs[indexes[0]][0].nullInstanceField)", e.getMessage(), "while trying to enter a null monitor loaded from field 'NullPointerExceptionTest.nullInstanceField' of an object loaded from an array");
-        }
-    }
-
-    /**
-     * @throws ClassNotFoundException
-     */
-    public void testInNative() throws ClassNotFoundException {
-        try {
-            Class.forName(null);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            Asserts.assertNull(e.getMessage());
-        }
-    }
-
-    private Object returnNull(String[][] dummy1, int[][][] dummy2, float dummy3) {
-        return null;
-    }
-
-    private NullPointerExceptionTest returnMeAsNull(Throwable dummy1, int dummy2, char dummy3){
-        return null;
-    }
-
-    static interface DoubleArrayGen {
-        public double[] getArray();
-    }
-
-    static class DoubleArrayGenImpl implements DoubleArrayGen {
-        @Override
-        public double[] getArray() {
-            return null;
-        }
-    }
-
-    static class NullPointerGenerator {
-        public static Object nullReturner(boolean dummy1) {
-            return null;
-        }
-
-        public Object returnMyNull(double dummy1, long dummy2, short dummy3) {
-            return null;
-        }
-    }
-
-    /**
-     *
-     */
-    public void testMissingLocalVariableTable() {
-        doTestMissingLocalVariableTable(names);
-
-        String[] expectedHasDebugInfoGoodNames = new String[] {
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference " +
-                "loaded from field 'NullPointerExceptionTest.nullInstanceField' " +
-                "of an object loaded from 'this'",
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " +
-                "local variable 'a1'",
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " +
-                "local variable 'o1'",
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " +
-                "local variable 'aa1'"
-        };
-
-        String[] expectedNoDebugInfoGoodNames = new String[] {
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference " +
-                "loaded from field 'NullPointerExceptionTest.nullInstanceField' " +
-                "of an object loaded from 'this'",
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " +
-                "the parameter nr. 5 of the method",
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " +
-                "the parameter nr. 2 of the method",
-            "while trying to invoke the method 'java.lang.Object.hashCode()I' on a null reference loaded from " +
-                "the parameter nr. 9 of the method"
-        };
-
-        String[] expectedNames;
-        if (hasDebugInfo) {
-            expectedNames = expectedHasDebugInfoGoodNames;
-        } else {
-            expectedNames = expectedNoDebugInfoGoodNames;
-        }
-
-        // The two lists of messages should have the same length.
-        Asserts.assertEquals(names.size(), expectedNames.length);
-
-        for (int i = 0; i < expectedNames.length; ++i) {
-            // GLGLGL not for now Asserts.assertEquals(names.get(i), expectedNames[i]);
-        }
-    }
-
-    private void doTestMissingLocalVariableTable(ArrayList<String> names) {
-        curr = names;
-        doTestMissingLocalVariableTable1();
-        doTestMissingLocalVariableTable2(-1, null, false, 0.0, null, 0.1f, (byte) 0, (short) 0, null);
-    }
-
-    private void doTestMissingLocalVariableTable1() {
-        try {
-            this.nullInstanceField.hashCode();
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            curr.add(e.getMessage());
-        }
-    }
-
-    private void doTestMissingLocalVariableTable2(long l1, Object o1, boolean z1, double d1, Object[] a1,
-            float f1, byte b1, short s1, Object[][] aa1) {
-        try {
-            a1.hashCode();
-            Asserts.fail();
-        }
-        catch (NullPointerException e) {
-            curr.add(e.getMessage());
-        }
-
-        try {
-            o1.hashCode();
-            Asserts.fail();
-        }
-        catch (NullPointerException e) {
-            curr.add(e.getMessage());
-        }
-
-        try {
-            aa1.hashCode();
-            Asserts.fail();
-        }
-        catch (NullPointerException e) {
-            curr.add(e.getMessage());
+            checkMessage("synchronized (objs[indexes[0]][0].nullInstanceField)", e.getMessage(),
+                         (hasDebugInfo ? "'objs[indexes" : "'<local2>[<local1>" ) + "[0]][0].nullInstanceField' is null. " +
+                         "Can not enter a null monitor.");
         }
     }
 
-    /**
-     *
-     */
-    @SuppressWarnings("null")
-    public void testNullMessages() {
-        boolean[] za1 = null;
-        byte[] ba1 = null;
-        short[] sa1 = null;
-        char[] ca1 = null;
-        int[] ia1 = null;
-        long[] la1 = null;
-        float[] fa1 = null;
-        double[] da1 = null;
-        Object[] oa1 = null;
-
-        Object[][] oa2 = new Object[2][];
-        oa2[1] = oa1;
-
-        try {
-            System.out.println(oa2[1][0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("oa2[1][0]", e.getMessage(),
-                                 "while trying to load from a null object array loaded from an array " +
-                                 "(which itself was loaded from " +
-                                 (hasDebugInfo ? "local variable 'oa2'" : "a local variable at slot 10") + ") " +
-                                 "with an index loaded from a constant");
-        }
-
-
-        try {
-            System.out.println(za1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("za1[0]", e.getMessage(),
-                                 "while trying to load from a null byte (or boolean) array loaded from " +
-                                 (hasDebugInfo ? "local variable 'za1'" : "a local variable at slot 1"));
-        }
-
-        try {
-            System.out.println(ba1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("ba1[0]", e.getMessage(),
-                                 "while trying to load from a null byte (or boolean) array loaded from " +
-                                 (hasDebugInfo ? "local variable 'ba1'" : "a local variable at slot 2"));
-        }
-
-        try {
-            System.out.println(sa1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("sa1[0]", e.getMessage(),
-                                 "while trying to load from a null short array loaded from " +
-                                 (hasDebugInfo ? "local variable 'sa1'" : "a local variable at slot 3"));
-        }
+    // Generates:
+    // class E implements E0 {
+    //     public int throwNPE(F f) {
+    //         return f.i;
+    //     }
+    // }
+    static byte[] generateTestClass() {
+        ClassWriter cw = new ClassWriter(0);
+        MethodVisitor mv;
 
-        try {
-            System.out.println(ca1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("ca1[0]", e.getMessage(),
-                                 "while trying to load from a null char array loaded from " +
-                                 (hasDebugInfo ? "local variable 'ca1'" : "a local variable at slot 4"));
-        }
-
-        try {
-            System.out.println(ia1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("ia1[0]", e.getMessage(),
-                                 "while trying to load from a null int array loaded from " +
-                                 (hasDebugInfo ? "local variable 'ia1'" : "a local variable at slot 5"));
-        }
-
-        try {
-            System.out.println(la1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("la1[0]", e.getMessage(),
-                                 "while trying to load from a null long array loaded from " +
-                                 (hasDebugInfo ? "local variable 'la1'" : "a local variable at slot 6"));
-        }
+        cw.visit(57, ACC_SUPER, "E", null, "java/lang/Object", new String[] { "E0" });
 
-        try {
-            System.out.println(fa1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("fa1[0]", e.getMessage(),
-                                 "while trying to load from a null float array loaded from " +
-                                 (hasDebugInfo ? "local variable 'fa1'" : "a local variable at slot 7"));
-        }
-
-        try {
-            System.out.println(da1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("da1[0]", e.getMessage(),
-                                 "while trying to load from a null double array loaded from " +
-                                 (hasDebugInfo ? "local variable 'da1'" : "a local variable at slot 8"));
-        }
-
-        try {
-            System.out.println(oa1[0]);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("oa1[0]", e.getMessage(),
-                                 "while trying to load from a null object array loaded from " +
-                                 (hasDebugInfo ? "local variable 'oa1'" : "a local variable at slot 9"));
-        }
-
-        try {
-            System.out.println(za1[0] = false);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("za1[0] = false", e.getMessage(),
-                                 "while trying to store to a null byte (or boolean) array loaded from " +
-                                 (hasDebugInfo ? "local variable 'za1'" : "a local variable at slot 1"));
-        }
-
-        try {
-            System.out.println(ba1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("ba1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null byte (or boolean) array loaded from " +
-                                 (hasDebugInfo ? "local variable 'ba1'" : "a local variable at slot 2"));
+        {
+            mv = cw.visitMethod(0, "<init>", "()V", null, null);
+            mv.visitCode();
+            mv.visitVarInsn(ALOAD, 0);
+            mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
+            mv.visitInsn(RETURN);
+            mv.visitMaxs(1, 1);
+            mv.visitEnd();
         }
 
-        try {
-            System.out.println(sa1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("sa1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null short array loaded from " +
-                                 (hasDebugInfo ? "local variable 'sa1'" : "a local variable at slot 3"));
+        {
+            mv = cw.visitMethod(ACC_PUBLIC, "throwNPE", "(LF;)I", null, null);
+            mv.visitCode();
+            Label label0 = new Label();
+            mv.visitLabel(label0);
+            mv.visitLineNumber(118, label0);
+            mv.visitVarInsn(ALOAD, 1);
+            mv.visitFieldInsn(GETFIELD, "F", "i", "I");
+            mv.visitInsn(IRETURN);
+            Label label1 = new Label();
+            mv.visitLabel(label1);
+            mv.visitLocalVariable("this", "LE;", null, label0, label1, 0);
+            mv.visitLocalVariable("f", "LE;", null, label0, label1, 1);
+            mv.visitMaxs(1, 2);
+            mv.visitEnd();
         }
-
-        try {
-            System.out.println(ca1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("ca1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null char array loaded from " +
-                                 (hasDebugInfo ? "local variable 'ca1'" : "a local variable at slot 4"));
-        }
-
-        try {
-            System.out.println(ia1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("ia1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null int array loaded from " +
-                                 (hasDebugInfo ? "local variable 'ia1'" : "a local variable at slot 5"));
-        }
+        cw.visitEnd();
 
-        try {
-            System.out.println(la1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("la1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null long array loaded from " +
-                                 (hasDebugInfo ? "local variable 'la1'" : "a local variable at slot 6"));
-        }
-
-        try {
-            System.out.println(fa1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("fa1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null float array loaded from " +
-                                 (hasDebugInfo ? "local variable 'fa1'" : "a local variable at slot 7"));
-        }
+        return cw.toByteArray();
+    }
 
-        try {
-            System.out.println(da1[0] = 0);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("da1[0] = 0", e.getMessage(),
-                                 "while trying to store to a null double array loaded from " +
-                                 (hasDebugInfo ? "local variable 'da1'" : "a local variable at slot 8"));
-        }
-
-        try {
-            System.out.println(oa1[0] = null);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("oa1[0] = null", e.getMessage(),
-                                 "while trying to store to a null object array loaded from " +
-                                 (hasDebugInfo ? "local variable 'oa1'" : "a local variable at slot 9"));
-        }
-
+    // Tests that a class generated on the fly is handled properly.
+    public void testGeneratedCode() throws Exception {
+        byte[] classBytes = generateTestClass();
+        Lookup lookup = lookup();
+        Class<?> clazz = lookup.defineClass(classBytes);
+        E0 e = (E0) clazz.getDeclaredConstructor().newInstance();
         try {
-            System.out.println(nullInstanceField.nullInstanceField);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("nullInstanceField.nullInstanceField", e.getMessage(),
-                                 "while trying to read the field 'nullInstanceField' of a null object loaded " +
-                                 "from field 'NullPointerExceptionTest.nullInstanceField' of an object " +
-                                 "loaded from 'this'");
-        }
-
-        try {
-            System.out.println(nullInstanceField.nullInstanceField = null);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("nullInstanceField.nullInstanceField = null", e.getMessage(),
-                                 "while trying to write the field 'NullPointerExceptionTest.nullInstanceField' " +
-                                 "of a null object loaded from field 'NullPointerExceptionTest.nullInstanceField' " +
-                                 "of an object loaded from 'this'");
-        }
-
-        try {
-            System.out.println(za1.length);
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("za1.length", e.getMessage(),
-                                 "while trying to get the length of a null array loaded from " +
-                                 (hasDebugInfo ? "local variable 'za1'" : "a local variable at slot 1"));
-        }
-
-        try {
-            throw null;
-        } catch (NullPointerException e) {
-            checkMessage("throw null", e.getMessage(),
-                                 "while trying to throw a null exception object loaded " +
-                                 "from a constant");
-        }
-
-        try {
-            synchronized (nullInstanceField) {
-                // desired
-            }
-        } catch (NullPointerException e) {
-            checkMessage("synchronized (nullInstanceField)", e.getMessage(),
-                                 "while trying to enter a null monitor loaded from field " +
-                                 "'NullPointerExceptionTest.nullInstanceField' of an object loaded from " +
-                                 "'this'");
-        }
-
-        try {
-            nullInstanceField.testCreationViaNew();
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("nullInstanceField.testCreationViaNew()", e.getMessage(),
-                                 "while trying to invoke the method 'NullPointerExceptionTest.testCreationViaNew()V' on a null reference " +
-                                 "loaded from field 'NullPointerExceptionTest.nullInstanceField' of an " +
-                                 "object loaded from 'this'");
-        }
-
-        try {
-            nullInstanceField.testNullMessages();
-            Asserts.fail();
-        } catch (NullPointerException e) {
-            checkMessage("nullInstanceField.testNullMessages()", e.getMessage(),
-                                 "while trying to invoke the method 'NullPointerExceptionTest.testNullMessages()V' on a null reference " +
-                                 "loaded from field 'NullPointerExceptionTest.nullInstanceField' of an " +
-                                 "object loaded from 'this'");
-        }
-
-        try {
-            // If we can get the value from more than one bci, we cannot know which one.
-            (Math.random() < 0.5 ? oa1 : (new Object[1])[0]).equals("");
-        } catch (NullPointerException e) {
-            checkMessage("(Math.random() < 0.5 ? oa1 : (new Object[1])[0]).equals(\"\")", e.getMessage(),
-                                 "while trying to invoke the method 'java.lang.Object.equals(Ljava/lang/Object;)Z' on a null reference");
+            e.throwNPE(null);
+        } catch (NullPointerException ex) {
+            checkMessage("return f.i;",
+                         ex.getMessage(),
+                         "'f' is null. Can not read field 'i'.");
         }
     }
 }
+
+// Helper interface for test cases needed for generateTestClass().
+interface E0 {
+    public int throwNPE(F f);
+}
+
+// Helper class for test cases needed for generateTestClass().
+class F {
+    int i;
+}