hotspot/agent/src/share/classes/sun/jvm/hotspot/oops/ConstantPool.java
changeset 1 489c9b5090e2
child 360 21d113ecbf6a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/agent/src/share/classes/sun/jvm/hotspot/oops/ConstantPool.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,481 @@
+/*
+ * Copyright 2000-2005 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.
+ *
+ */
+
+package sun.jvm.hotspot.oops;
+
+import java.io.*;
+import java.util.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.runtime.*;
+import sun.jvm.hotspot.types.*;
+import sun.jvm.hotspot.utilities.*;
+
+// A ConstantPool is an array containing class constants
+// as described in the class file
+
+public class ConstantPool extends Array implements ClassConstants {
+  // Used for debugging this code
+  private static final boolean DEBUG = false;
+
+  protected void debugMessage(String message) {
+    System.out.println(message);
+  }
+
+  static {
+    VM.registerVMInitializedObserver(new Observer() {
+        public void update(Observable o, Object data) {
+          initialize(VM.getVM().getTypeDataBase());
+        }
+      });
+  }
+
+  private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
+    Type type   = db.lookupType("constantPoolOopDesc");
+    tags        = new OopField(type.getOopField("_tags"), 0);
+    cache       = new OopField(type.getOopField("_cache"), 0);
+    poolHolder  = new OopField(type.getOopField("_pool_holder"), 0);
+    headerSize  = type.getSize();
+    elementSize = db.getOopSize();
+  }
+
+  ConstantPool(OopHandle handle, ObjectHeap heap) {
+    super(handle, heap);
+  }
+
+  public boolean isConstantPool()      { return true; }
+
+  private static OopField tags;
+  private static OopField cache;
+  private static OopField poolHolder;
+
+
+  private static long headerSize;
+  private static long elementSize;
+
+  public TypeArray         getTags()       { return (TypeArray)         tags.getValue(this); }
+  public ConstantPoolCache getCache()      { return (ConstantPoolCache) cache.getValue(this); }
+  public Klass             getPoolHolder() { return (Klass)             poolHolder.getValue(this); }
+
+  private long indexOffset(long index) {
+    if (Assert.ASSERTS_ENABLED) {
+      Assert.that(index > 0 && index < getLength(),  "invalid cp index");
+    }
+    return (index * elementSize) + headerSize;
+  }
+
+  public ConstantTag getTagAt(long index) {
+    return new ConstantTag(getTags().getByteAt((int) index));
+  }
+
+  public Oop getObjAt(long index){
+    return getHeap().newOop(getHandle().getOopHandleAt(indexOffset(index)));
+  }
+
+  public Symbol getSymbolAt(long index) {
+    return (Symbol) getObjAt(index);
+  }
+
+  public int getIntAt(long index){
+    return getHandle().getJIntAt(indexOffset(index));
+  }
+
+  public float getFloatAt(long index){
+    return getHandle().getJFloatAt(indexOffset(index));
+  }
+
+  public long getLongAt(long index) {
+    int oneHalf = getHandle().getJIntAt(indexOffset(index + 1));
+    int otherHalf   = getHandle().getJIntAt(indexOffset(index));
+    // buildLongFromIntsPD accepts higher address value, lower address value
+    // in that order.
+    return VM.getVM().buildLongFromIntsPD(oneHalf, otherHalf);
+  }
+
+  public double getDoubleAt(long index) {
+    return Double.longBitsToDouble(getLongAt(index));
+  }
+
+  public int getFieldOrMethodAt(int which) {
+    if (DEBUG) {
+      System.err.print("ConstantPool.getFieldOrMethodAt(" + which + "): new index = ");
+    }
+    int i = -1;
+    ConstantPoolCache cache = getCache();
+    if (cache == null) {
+      i = which;
+    } else {
+      // change byte-ordering and go via cache
+      i = cache.getEntryAt(0xFFFF & VM.getVM().getBytes().swapShort((short) which)).getConstantPoolIndex();
+    }
+    if (Assert.ASSERTS_ENABLED) {
+      Assert.that(getTagAt(i).isFieldOrMethod(), "Corrupted constant pool");
+    }
+    if (DEBUG) {
+      System.err.println(i);
+    }
+    int res = getIntAt(i);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getFieldOrMethodAt(" + i + "): result = " + res);
+    }
+    return res;
+  }
+
+  public int getNameAndTypeAt(int which) {
+    if (Assert.ASSERTS_ENABLED) {
+      Assert.that(getTagAt(which).isNameAndType(), "Corrupted constant pool");
+    }
+    int i = getIntAt(which);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getNameAndTypeAt(" + which + "): result = " + i);
+    }
+    return i;
+  }
+
+  public Symbol getNameRefAt(int which) {
+    int refIndex = getNameAndTypeAt(getNameAndTypeRefIndexAt(which));
+    int nameIndex = extractLowShortFromInt(refIndex);
+    return getSymbolAt(nameIndex);
+  }
+
+  public Symbol getSignatureRefAt(int which) {
+    int refIndex = getNameAndTypeAt(getNameAndTypeRefIndexAt(which));
+    int sigIndex = extractHighShortFromInt(refIndex);
+    return getSymbolAt(sigIndex);
+  }
+
+  // returns null, if not resolved.
+  public Klass getKlassRefAt(int which) {
+    if( ! getTagAt(which).isKlass()) return null;
+    return (Klass) getObjAt(which);
+  }
+
+  // returns null, if not resolved.
+  public InstanceKlass getFieldOrMethodKlassRefAt(int which) {
+    int refIndex = getFieldOrMethodAt(which);
+    int klassIndex = extractLowShortFromInt(refIndex);
+    return (InstanceKlass) getKlassRefAt(klassIndex);
+  }
+
+  // returns null, if not resolved.
+  public Method getMethodRefAt(int which) {
+    InstanceKlass klass = getFieldOrMethodKlassRefAt(which);
+    if (klass == null) return null;
+    Symbol name = getNameRefAt(which);
+    Symbol sig  = getSignatureRefAt(which);
+    return klass.findMethod(name, sig);
+  }
+
+  // returns null, if not resolved.
+  public Field getFieldRefAt(int which) {
+    InstanceKlass klass = getFieldOrMethodKlassRefAt(which);
+    if (klass == null) return null;
+    Symbol name = getNameRefAt(which);
+    Symbol sig  = getSignatureRefAt(which);
+    return klass.findField(name, sig);
+  }
+
+  public int getNameAndTypeRefIndexAt(int index) {
+    int refIndex = getFieldOrMethodAt(index);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getNameAndTypeRefIndexAt(" + index + "): refIndex = " + refIndex);
+    }
+    int i = extractHighShortFromInt(refIndex);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getNameAndTypeRefIndexAt(" + index + "): result = " + i);
+    }
+    return i;
+  }
+
+  /** Lookup for entries consisting of (name_index, signature_index) */
+  public int getNameRefIndexAt(int index) {
+    int refIndex = getNameAndTypeAt(index);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getNameRefIndexAt(" + index + "): refIndex = " + refIndex);
+    }
+    int i = extractLowShortFromInt(refIndex);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getNameRefIndexAt(" + index + "): result = " + i);
+    }
+    return i;
+  }
+
+  /** Lookup for entries consisting of (name_index, signature_index) */
+  public int getSignatureRefIndexAt(int index) {
+    int refIndex = getNameAndTypeAt(index);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getSignatureRefIndexAt(" + index + "): refIndex = " + refIndex);
+    }
+    int i = extractHighShortFromInt(refIndex);
+    if (DEBUG) {
+      System.err.println("ConstantPool.getSignatureRefIndexAt(" + index + "): result = " + i);
+    }
+    return i;
+  }
+
+  final private static String[] nameForTag = new String[] {
+  };
+
+  private String nameForTag(int tag) {
+    switch (tag) {
+    case JVM_CONSTANT_Utf8:               return "JVM_CONSTANT_Utf8";
+    case JVM_CONSTANT_Unicode:            return "JVM_CONSTANT_Unicode";
+    case JVM_CONSTANT_Integer:            return "JVM_CONSTANT_Integer";
+    case JVM_CONSTANT_Float:              return "JVM_CONSTANT_Float";
+    case JVM_CONSTANT_Long:               return "JVM_CONSTANT_Long";
+    case JVM_CONSTANT_Double:             return "JVM_CONSTANT_Double";
+    case JVM_CONSTANT_Class:              return "JVM_CONSTANT_Class";
+    case JVM_CONSTANT_String:             return "JVM_CONSTANT_String";
+    case JVM_CONSTANT_Fieldref:           return "JVM_CONSTANT_Fieldref";
+    case JVM_CONSTANT_Methodref:          return "JVM_CONSTANT_Methodref";
+    case JVM_CONSTANT_InterfaceMethodref: return "JVM_CONSTANT_InterfaceMethodref";
+    case JVM_CONSTANT_NameAndType:        return "JVM_CONSTANT_NameAndType";
+    case JVM_CONSTANT_Invalid:            return "JVM_CONSTANT_Invalid";
+    case JVM_CONSTANT_UnresolvedClass:    return "JVM_CONSTANT_UnresolvedClass";
+    case JVM_CONSTANT_ClassIndex:         return "JVM_CONSTANT_ClassIndex";
+    case JVM_CONSTANT_UnresolvedString:   return "JVM_CONSTANT_UnresolvedString";
+    case JVM_CONSTANT_StringIndex:        return "JVM_CONSTANT_StringIndex";
+    }
+    throw new InternalError("unknown tag");
+  }
+
+  public void iterateFields(OopVisitor visitor, boolean doVMFields) {
+    super.iterateFields(visitor, doVMFields);
+    if (doVMFields) {
+      visitor.doOop(tags, true);
+      visitor.doOop(cache, true);
+      visitor.doOop(poolHolder, true);
+
+      final int length = (int) getLength();
+      // zero'th pool entry is always invalid. ignore it.
+      for (int index = 1; index < length; index++) {
+        int ctag = (int) getTags().getByteAt((int) index);
+        switch (ctag) {
+        case JVM_CONSTANT_ClassIndex:
+        case JVM_CONSTANT_StringIndex:
+        case JVM_CONSTANT_Integer:
+          visitor.doInt(new IntField(new NamedFieldIdentifier(nameForTag(ctag)), indexOffset(index), true), true);
+          break;
+
+        case JVM_CONSTANT_Float:
+          visitor.doFloat(new FloatField(new NamedFieldIdentifier(nameForTag(ctag)), indexOffset(index), true), true);
+          break;
+
+        case JVM_CONSTANT_Long:
+          visitor.doLong(new LongField(new NamedFieldIdentifier(nameForTag(ctag)), indexOffset(index), true), true);
+          // long entries occupy two slots
+          index++;
+          break;
+
+        case JVM_CONSTANT_Double:
+          visitor.doDouble(new DoubleField(new NamedFieldIdentifier(nameForTag(ctag)), indexOffset(index), true), true);
+          // double entries occupy two slots
+          index++;
+          break;
+
+        case JVM_CONSTANT_UnresolvedClass:
+        case JVM_CONSTANT_Class:
+        case JVM_CONSTANT_UnresolvedString:
+        case JVM_CONSTANT_Utf8:
+          visitor.doOop(new OopField(new NamedFieldIdentifier(nameForTag(ctag)), indexOffset(index), true), true);
+          break;
+
+        case JVM_CONSTANT_Fieldref:
+        case JVM_CONSTANT_Methodref:
+        case JVM_CONSTANT_InterfaceMethodref:
+        case JVM_CONSTANT_NameAndType:
+          visitor.doInt(new IntField(new NamedFieldIdentifier(nameForTag(ctag)), indexOffset(index), true), true);
+          break;
+        }
+      }
+    }
+    /*
+    int length = getLength();
+    for (int index = 0; index < length; index++) {
+      long offset = baseOffset + (index + typeDataBase.getOopSize());
+      visitor.doOop(new IndexableField(index, offset, false), getObjAt(index));
+    }
+    */
+  }
+
+  public void writeBytes(OutputStream os) throws IOException {
+          // Map between any modified UTF-8 and it's constant pool index.
+          Map utf8ToIndex = new HashMap();
+      DataOutputStream dos = new DataOutputStream(os);
+      TypeArray tags = getTags();
+      int len = (int)getLength();
+      int ci = 0; // constant pool index
+
+      // collect all modified UTF-8 Strings from Constant Pool
+
+      for (ci = 1; ci < len; ci++) {
+          byte cpConstType = tags.getByteAt(ci);
+          if(cpConstType == JVM_CONSTANT_Utf8) {
+              Symbol sym = getSymbolAt(ci);
+              utf8ToIndex.put(sym.asString(), new Short((short) ci));
+          }
+          else if(cpConstType == JVM_CONSTANT_Long ||
+                  cpConstType == JVM_CONSTANT_Double) {
+              ci++;
+          }
+      }
+
+
+      for(ci = 1; ci < len; ci++) {
+          int cpConstType = (int)tags.getByteAt(ci);
+          // write cp_info
+          // write constant type
+          switch(cpConstType) {
+              case JVM_CONSTANT_Utf8: {
+                  dos.writeByte(cpConstType);
+                  Symbol sym = getSymbolAt(ci);
+                  dos.writeShort((short)sym.getLength());
+                  dos.write(sym.asByteArray());
+                  if (DEBUG) debugMessage("CP[" + ci + "] = modified UTF-8 " + sym.asString());
+                  break;
+              }
+
+              case JVM_CONSTANT_Unicode:
+                  throw new IllegalArgumentException("Unicode constant!");
+
+              case JVM_CONSTANT_Integer:
+                  dos.writeByte(cpConstType);
+                  dos.writeInt(getIntAt(ci));
+                  if (DEBUG) debugMessage("CP[" + ci + "] = int " + getIntAt(ci));
+                  break;
+
+              case JVM_CONSTANT_Float:
+                  dos.writeByte(cpConstType);
+                  dos.writeFloat(getFloatAt(ci));
+                  if (DEBUG) debugMessage("CP[" + ci + "] = float " + getFloatAt(ci));
+                  break;
+
+              case JVM_CONSTANT_Long: {
+                  dos.writeByte(cpConstType);
+                  long l = getLongAt(ci);
+                  // long entries occupy two pool entries
+                  ci++;
+                  dos.writeLong(l);
+                  break;
+              }
+
+              case JVM_CONSTANT_Double:
+                  dos.writeByte(cpConstType);
+                  dos.writeDouble(getDoubleAt(ci));
+                  // double entries occupy two pool entries
+                  ci++;
+                  break;
+
+              case JVM_CONSTANT_Class: {
+                  dos.writeByte(cpConstType);
+                  // Klass already resolved. ConstantPool constains klassOop.
+                  Klass refKls = (Klass) getObjAt(ci);
+                  String klassName = refKls.getName().asString();
+                  Short s = (Short) utf8ToIndex.get(klassName);
+                  dos.writeShort(s.shortValue());
+                  if (DEBUG) debugMessage("CP[" + ci  + "] = class " + s);
+                  break;
+              }
+
+              // case JVM_CONSTANT_ClassIndex:
+              case JVM_CONSTANT_UnresolvedClass: {
+                  dos.writeByte(JVM_CONSTANT_Class);
+                  String klassName = getSymbolAt(ci).asString();
+                  Short s = (Short) utf8ToIndex.get(klassName);
+                  dos.writeShort(s.shortValue());
+                  if (DEBUG) debugMessage("CP[" + ci + "] = class " + s);
+                  break;
+              }
+
+              case JVM_CONSTANT_String: {
+                  dos.writeByte(cpConstType);
+                  String str = OopUtilities.stringOopToString(getObjAt(ci));
+                  Short s = (Short) utf8ToIndex.get(str);
+                  dos.writeShort(s.shortValue());
+                  if (DEBUG) debugMessage("CP[" + ci + "] = string " + s);
+                  break;
+              }
+
+                  // case JVM_CONSTANT_StringIndex:
+              case JVM_CONSTANT_UnresolvedString: {
+                  dos.writeByte(JVM_CONSTANT_String);
+                  String val = getSymbolAt(ci).asString();
+
+                  Short s = (Short) utf8ToIndex.get(val);
+                  dos.writeShort(s.shortValue());
+                  if (DEBUG) debugMessage("CP[" + ci + "] = string " + s);
+                  break;
+              }
+
+              // all external, internal method/field references
+              case JVM_CONSTANT_Fieldref:
+              case JVM_CONSTANT_Methodref:
+              case JVM_CONSTANT_InterfaceMethodref: {
+                  dos.writeByte(cpConstType);
+                  int value = getIntAt(ci);
+                  short klassIndex = (short) extractLowShortFromInt(value);
+                  short nameAndTypeIndex = (short) extractHighShortFromInt(value);
+                  dos.writeShort(klassIndex);
+                  dos.writeShort(nameAndTypeIndex);
+                  if (DEBUG) debugMessage("CP[" + ci + "] = ref klass = " +
+                                          klassIndex + ", N&T = " + nameAndTypeIndex);
+                  break;
+              }
+
+              case JVM_CONSTANT_NameAndType: {
+                  dos.writeByte(cpConstType);
+                  int value = getIntAt(ci);
+                  short nameIndex = (short) extractLowShortFromInt(value);
+                  short signatureIndex = (short) extractHighShortFromInt(value);
+                  dos.writeShort(nameIndex);
+                  dos.writeShort(signatureIndex);
+                  if (DEBUG) debugMessage("CP[" + ci + "] = N&T name = " + nameIndex
+                                          + ", type = " + signatureIndex);
+                  break;
+              }
+          } // switch
+      }
+      dos.flush();
+      return;
+  }
+
+  public void printValueOn(PrintStream tty) {
+    tty.print("ConstantPool for " + getPoolHolder().getName().asString());
+  }
+
+  public long getObjectSize() {
+    return alignObjectSize(headerSize + (getLength() * elementSize));
+  }
+
+  //----------------------------------------------------------------------
+  // Internals only below this point
+  //
+
+  private static int extractHighShortFromInt(int val) {
+    return (val >> 16) & 0xFFFF;
+  }
+
+  private static int extractLowShortFromInt(int val) {
+    return val & 0xFFFF;
+  }
+}