1 /* 2 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 package sun.jvm.hotspot.oops; 26 27 import java.io.*; 28 import java.util.*; 29 import sun.jvm.hotspot.debugger.*; 30 import sun.jvm.hotspot.runtime.*; 31 import sun.jvm.hotspot.types.*; 32 import sun.jvm.hotspot.utilities.*; 33 34 // ConstantPoolCache : A constant pool cache (ConstantPoolCache). 35 // See cpCache.hpp for details about this class. 36 // 37 public class ConstantPoolCache extends Metadata { 38 static { VM.registerVMInitializedObserver(new Observer() { public void update(Observable o, Object data) { initialize(VM.getVM().getTypeDataBase()); } })39 VM.registerVMInitializedObserver(new Observer() { 40 public void update(Observable o, Object data) { 41 initialize(VM.getVM().getTypeDataBase()); 42 } 43 }); 44 } 45 initialize(TypeDataBase db)46 private static synchronized void initialize(TypeDataBase db) throws WrongTypeException { 47 Type type = db.lookupType("ConstantPoolCache"); 48 constants = new MetadataField(type.getAddressField("_constant_pool"), 0); 49 baseOffset = type.getSize(); 50 Type elType = db.lookupType("ConstantPoolCacheEntry"); 51 elementSize = elType.getSize(); 52 length = new CIntField(type.getCIntegerField("_length"), 0); 53 intSize = VM.getVM().getObjectHeap().getIntSize(); 54 resolvedReferences = type.getAddressField("_resolved_references"); 55 referenceMap = type.getAddressField("_reference_map"); 56 } 57 ConstantPoolCache(Address addr)58 public ConstantPoolCache(Address addr) { 59 super(addr); 60 } 61 isConstantPoolCache()62 public boolean isConstantPoolCache() { return true; } 63 64 private static MetadataField constants; 65 66 private static long baseOffset; 67 private static long elementSize; 68 private static CIntField length; 69 private static long intSize; 70 private static AddressField resolvedReferences; 71 private static AddressField referenceMap; 72 getConstants()73 public ConstantPool getConstants() { return (ConstantPool) constants.getValue(this); } 74 getSize()75 public long getSize() { 76 return alignSize(baseOffset + getLength() * elementSize); 77 } 78 getEntryAt(int i)79 public ConstantPoolCacheEntry getEntryAt(int i) { 80 if (i < 0 || i >= getLength()) throw new IndexOutOfBoundsException(i + " " + getLength()); 81 return new ConstantPoolCacheEntry(this, i); 82 } 83 getIntAt(int entry, int fld)84 public int getIntAt(int entry, int fld) { 85 long offset = baseOffset + entry * elementSize + fld * intSize; 86 return (int) getAddress().getCIntegerAt(offset, intSize, true ); 87 } 88 89 printValueOn(PrintStream tty)90 public void printValueOn(PrintStream tty) { 91 tty.print("ConstantPoolCache for " + getConstants().getPoolHolder().getName().asString() + " address = " + getAddress() + " offset = " + baseOffset); 92 } 93 getLength()94 public int getLength() { 95 return (int) length.getValue(getAddress()); 96 } 97 iterateFields(MetadataVisitor visitor)98 public void iterateFields(MetadataVisitor visitor) { 99 super.iterateFields(visitor); 100 visitor.doMetadata(constants, true); 101 for (int i = 0; i < getLength(); i++) { 102 ConstantPoolCacheEntry entry = getEntryAt(i); 103 entry.iterateFields(visitor); 104 } 105 } 106 getResolvedReferences()107 public Oop getResolvedReferences() { 108 Address handle = resolvedReferences.getValue(getAddress()); 109 if (handle != null) { 110 // Load through the handle 111 OopHandle refs = handle.getOopHandleAt(0); 112 return VM.getVM().getObjectHeap().newOop(refs); 113 } 114 return null; 115 } 116 referenceMap()117 public U2Array referenceMap() { 118 return new U2Array(referenceMap.getValue(getAddress())); 119 } 120 }; 121