1 /* 2 * Copyright (c) 2000, 2011, 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 (constantPoolCacheOopDesc). 35 // See cpCacheOop.hpp for details about this class. 36 // 37 public class ConstantPoolCache extends Oop { 38 static { 39 VM.registerVMInitializedObserver(new Observer() { 40 public void update(Observable o, Object data) { 41 initialize(VM.getVM().getTypeDataBase()); 42 } 43 }); 44 } 45 46 private static synchronized void initialize(TypeDataBase db) throws WrongTypeException { 47 Type type = db.lookupType("constantPoolCacheOopDesc"); 48 constants = new OopField(type.getOopField("_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 } 54 55 ConstantPoolCache(OopHandle handle, ObjectHeap heap) { 56 super(handle, heap); 57 } 58 59 public boolean isConstantPoolCache() { return true; } 60 61 private static OopField constants; 62 63 private static long baseOffset; 64 private static long elementSize; 65 private static CIntField length; 66 67 68 public ConstantPool getConstants() { return (ConstantPool) constants.getValue(this); } 69 70 public long getObjectSize() { 71 return alignObjectSize(baseOffset + getLength() * elementSize); 72 } 73 74 public ConstantPoolCacheEntry getEntryAt(int i) { 75 if (i < 0 || i >= getLength()) throw new IndexOutOfBoundsException(i + " " + getLength()); 76 return new ConstantPoolCacheEntry(this, i); 77 } 78 79 public static boolean isSecondaryIndex(int i) { return (i < 0); } 80 public static int decodeSecondaryIndex(int i) { return isSecondaryIndex(i) ? ~i : i; } 81 public static int encodeSecondaryIndex(int i) { return !isSecondaryIndex(i) ? ~i : i; } 82 83 // secondary entries hold invokedynamic call site bindings 84 public ConstantPoolCacheEntry getSecondaryEntryAt(int i) { 85 int rawIndex = i; 86 if (isSecondaryIndex(i)) { 87 rawIndex = decodeSecondaryIndex(i); 88 } 89 ConstantPoolCacheEntry e = getEntryAt(rawIndex); 90 if (Assert.ASSERTS_ENABLED) { 91 Assert.that(e.isSecondaryEntry(), "must be a secondary entry:" + rawIndex); 92 } 93 return e; 94 } 95 96 public ConstantPoolCacheEntry getMainEntryAt(int i) { 97 int primaryIndex = i; 98 if (isSecondaryIndex(i)) { 99 // run through an extra level of indirection: 100 int rawIndex = decodeSecondaryIndex(i); 101 primaryIndex = getEntryAt(rawIndex).getMainEntryIndex(); 102 } 103 ConstantPoolCacheEntry e = getEntryAt(primaryIndex); 104 if (Assert.ASSERTS_ENABLED) { 105 Assert.that(!e.isSecondaryEntry(), "must not be a secondary entry:" + primaryIndex); 106 } 107 return e; 108 } 109 110 public int getIntAt(int entry, int fld) { 111 //alignObjectSize ? 112 long offset = baseOffset + /*alignObjectSize*/entry * elementSize + fld* getHeap().getIntSize(); 113 return (int) getHandle().getCIntegerAt(offset, getHeap().getIntSize(), true ); 114 } 115 116 117 public void printValueOn(PrintStream tty) { 118 tty.print("ConstantPoolCache for " + getConstants().getPoolHolder().getName().asString()); 119 } 120 121 public int getLength() { 122 return (int) length.getValue(this); 123 } 124 125 public void iterateFields(OopVisitor visitor, boolean doVMFields) { 126 super.iterateFields(visitor, doVMFields); 127 if (doVMFields) { 128 visitor.doOop(constants, true); 129 for (int i = 0; i < getLength(); i++) { 130 ConstantPoolCacheEntry entry = getEntryAt(i); 131 entry.iterateFields(visitor); 132 } 133 } 134 } 135 };