hotspot/src/share/vm/oops/arrayKlass.cpp
changeset 1 489c9b5090e2
child 3576 4ceec8fb3e18
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/arrayKlass.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,199 @@
+/*
+ * Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_arrayKlass.cpp.incl"
+
+int arrayKlass::object_size(int header_size) const {
+  // size of an array klass object
+  assert(header_size <= instanceKlass::header_size(), "bad header size");
+  // If this assert fails, see comments in base_create_array_klass.
+  header_size = instanceKlass::header_size();
+#ifdef _LP64
+  int size = header_size + align_object_offset(vtable_length());
+#else
+  int size = header_size + vtable_length();
+#endif
+  return align_object_size(size);
+}
+
+
+klassOop arrayKlass::java_super() const {
+  if (super() == NULL)  return NULL;  // bootstrap case
+  // Array klasses have primary supertypes which are not reported to Java.
+  // Example super chain:  String[][] -> Object[][] -> Object[] -> Object
+  return SystemDictionary::object_klass();
+}
+
+
+oop arrayKlass::multi_allocate(int rank, jint* sizes, TRAPS) {
+  ShouldNotReachHere();
+  return NULL;
+}
+
+methodOop arrayKlass::uncached_lookup_method(symbolOop name, symbolOop signature) const {
+  // There are no methods in an array klass but the super class (Object) has some
+  assert(super(), "super klass must be present");
+  return Klass::cast(super())->uncached_lookup_method(name, signature);
+}
+
+
+arrayKlassHandle arrayKlass::base_create_array_klass(
+const Klass_vtbl& cplusplus_vtbl, int header_size, KlassHandle klass, TRAPS) {
+  // Allocation
+  // Note: because the Java vtable must start at the same offset in all klasses,
+  // we must insert filler fields into arrayKlass to make it the same size as instanceKlass.
+  // If this assert fails, add filler to instanceKlass to make it bigger.
+  assert(header_size <= instanceKlass::header_size(),
+         "array klasses must be same size as instanceKlass");
+  header_size = instanceKlass::header_size();
+  // Arrays don't add any new methods, so their vtable is the same size as
+  // the vtable of klass Object.
+  int vtable_size = Universe::base_vtable_size();
+  arrayKlassHandle k;
+  KlassHandle base_klass = Klass::base_create_klass(klass,
+                                                 header_size + vtable_size,
+                                                 cplusplus_vtbl, CHECK_(k));
+
+  // No safepoint should be possible until the handle's
+  // target below becomes parsable
+  No_Safepoint_Verifier no_safepoint;
+  k = arrayKlassHandle(THREAD, base_klass());
+
+  assert(!k()->is_parsable(), "not expecting parsability yet.");
+  k->set_super(Universe::is_bootstrapping() ? (klassOop)NULL : SystemDictionary::object_klass());
+  k->set_layout_helper(Klass::_lh_neutral_value);
+  k->set_dimension(1);
+  k->set_higher_dimension(NULL);
+  k->set_lower_dimension(NULL);
+  k->set_component_mirror(NULL);
+  k->set_vtable_length(vtable_size);
+  k->set_is_cloneable(); // All arrays are considered to be cloneable (See JLS 20.1.5)
+
+  assert(k()->is_parsable(), "should be parsable here.");
+  // Make sure size calculation is right
+  assert(k()->size() == align_object_size(header_size + vtable_size), "wrong size for object");
+
+  return k;
+}
+
+
+// Initialization of vtables and mirror object is done separatly from base_create_array_klass,
+// since a GC can happen. At this point all instance variables of the arrayKlass must be setup.
+void arrayKlass::complete_create_array_klass(arrayKlassHandle k, KlassHandle super_klass, TRAPS) {
+  ResourceMark rm(THREAD);
+  k->initialize_supers(super_klass(), CHECK);
+  k->vtable()->initialize_vtable(false, CHECK);
+  java_lang_Class::create_mirror(k, CHECK);
+}
+
+objArrayOop arrayKlass::compute_secondary_supers(int num_extra_slots, TRAPS) {
+  // interfaces = { cloneable_klass, serializable_klass };
+  assert(num_extra_slots == 0, "sanity of primitive array type");
+  // Must share this for correct bootstrapping!
+  return Universe::the_array_interfaces_array();
+}
+
+bool arrayKlass::compute_is_subtype_of(klassOop k) {
+  // An array is a subtype of Serializable, Clonable, and Object
+  return    k == SystemDictionary::object_klass()
+         || k == SystemDictionary::cloneable_klass()
+         || k == SystemDictionary::serializable_klass();
+}
+
+
+inline intptr_t* arrayKlass::start_of_vtable() const {
+  // all vtables start at the same place, that's why we use instanceKlass::header_size here
+  return ((intptr_t*)as_klassOop()) + instanceKlass::header_size();
+}
+
+
+klassVtable* arrayKlass::vtable() const {
+  KlassHandle kh(Thread::current(), as_klassOop());
+  return new klassVtable(kh, start_of_vtable(), vtable_length() / vtableEntry::size());
+}
+
+
+objArrayOop arrayKlass::allocate_arrayArray(int n, int length, TRAPS) {
+  if (length < 0) {
+    THROW_0(vmSymbols::java_lang_NegativeArraySizeException());
+  }
+  if (length > arrayOopDesc::max_array_length(T_ARRAY)) {
+    THROW_OOP_0(Universe::out_of_memory_error_array_size());
+  }
+  int size = objArrayOopDesc::object_size(length);
+  klassOop k = array_klass(n+dimension(), CHECK_0);
+  arrayKlassHandle ak (THREAD, k);
+  objArrayOop o =
+    (objArrayOop)CollectedHeap::array_allocate(ak, size, length, CHECK_0);
+  // initialization to NULL not necessary, area already cleared
+  return o;
+}
+
+
+void arrayKlass::array_klasses_do(void f(klassOop k)) {
+  klassOop k = as_klassOop();
+  // Iterate over this array klass and all higher dimensions
+  while (k != NULL) {
+    f(k);
+    k = arrayKlass::cast(k)->higher_dimension();
+  }
+}
+
+
+void arrayKlass::with_array_klasses_do(void f(klassOop k)) {
+  array_klasses_do(f);
+}
+
+// JVM support
+
+jint arrayKlass::compute_modifier_flags(TRAPS) const {
+  return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
+}
+
+// JVMTI support
+
+jint arrayKlass::jvmti_class_status() const {
+  return JVMTI_CLASS_STATUS_ARRAY;
+}
+
+#ifndef PRODUCT
+
+// Printing
+
+void arrayKlass::oop_print_on(oop obj, outputStream* st) {
+  assert(obj->is_array(), "must be array");
+  Klass::oop_print_on(obj, st);
+  st->print_cr(" - length: %d", arrayOop(obj)->length());
+}
+
+#endif
+
+// Verification
+
+void arrayKlass::oop_verify_on(oop obj, outputStream* st) {
+  guarantee(obj->is_array(), "must be array");
+  arrayOop a = arrayOop(obj);
+  guarantee(a->length() >= 0, "array with negative length?");
+}