1 /* 2 * [The "BSD licence"] 3 * Copyright (c) 2010 Ben Gruver (JesusFreke) 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 package org.jf.dexlib.Code; 30 31 import org.jf.dexlib.*; 32 import org.jf.dexlib.Util.NumberUtils; 33 34 public abstract class InstructionWithReference extends Instruction { 35 private Item referencedItem; 36 private ReferenceType referenceType; 37 InstructionWithReference(Opcode opcode, Item referencedItem)38 protected InstructionWithReference(Opcode opcode, Item referencedItem) { 39 super(opcode); 40 this.referencedItem = referencedItem; 41 this.referenceType = opcode.referenceType; 42 checkReferenceType(); 43 } 44 InstructionWithReference(Opcode opcode, Item referencedItem, ReferenceType referenceType)45 protected InstructionWithReference(Opcode opcode, Item referencedItem, ReferenceType referenceType) { 46 super(opcode); 47 this.referencedItem = referencedItem; 48 this.referenceType = referenceType; 49 checkReferenceType(); 50 } 51 InstructionWithReference(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex)52 protected InstructionWithReference(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) { 53 super(opcode); 54 55 this.referenceType = readReferenceType(opcode, buffer, bufferIndex); 56 int itemIndex = getReferencedItemIndex(buffer, bufferIndex); 57 lookupReferencedItem(dexFile, opcode, itemIndex); 58 } 59 getReferencedItemIndex(byte[] buffer, int bufferIndex)60 protected int getReferencedItemIndex(byte[] buffer, int bufferIndex) { 61 return NumberUtils.decodeUnsignedShort(buffer, bufferIndex + 2); 62 } 63 getReferenceType()64 public ReferenceType getReferenceType() { 65 return referenceType; 66 } 67 getReferencedItem()68 public Item getReferencedItem() { 69 return referencedItem; 70 } 71 readReferenceType(Opcode opcode, byte[] buffer, int bufferIndex)72 protected ReferenceType readReferenceType(Opcode opcode, byte[] buffer, int bufferIndex) { 73 return opcode.referenceType; 74 } 75 lookupReferencedItem(DexFile dexFile, Opcode opcode, int itemIndex)76 private void lookupReferencedItem(DexFile dexFile, Opcode opcode, int itemIndex) { 77 switch (referenceType) { 78 case field: 79 referencedItem = dexFile.FieldIdsSection.getItemByIndex(itemIndex); 80 return; 81 case method: 82 referencedItem = dexFile.MethodIdsSection.getItemByIndex(itemIndex); 83 return; 84 case type: 85 referencedItem = dexFile.TypeIdsSection.getItemByIndex(itemIndex); 86 return; 87 case string: 88 referencedItem = dexFile.StringIdsSection.getItemByIndex(itemIndex); 89 } 90 } 91 92 checkReferenceType()93 private void checkReferenceType() { 94 switch (referenceType) { 95 case field: 96 if (!(referencedItem instanceof FieldIdItem)) { 97 throw new RuntimeException(referencedItem.getClass().getSimpleName() + 98 " is the wrong item type for opcode " + opcode.name + ". Expecting FieldIdItem."); 99 } 100 return; 101 case method: 102 if (!(referencedItem instanceof MethodIdItem)) { 103 throw new RuntimeException(referencedItem.getClass().getSimpleName() + 104 " is the wrong item type for opcode " + opcode.name + ". Expecting MethodIdItem."); 105 } 106 return; 107 case type: 108 if (!(referencedItem instanceof TypeIdItem)) { 109 throw new RuntimeException(referencedItem.getClass().getSimpleName() + 110 " is the wrong item type for opcode " + opcode.name + ". Expecting TypeIdItem."); 111 } 112 return; 113 case string: 114 if (!(referencedItem instanceof StringIdItem)) { 115 throw new RuntimeException(referencedItem.getClass().getSimpleName() + 116 " is the wrong item type for opcode " + opcode.name + ". Expecting StringIdItem."); 117 } 118 return; 119 default: 120 if (referencedItem != null) { 121 throw new RuntimeException(referencedItem.getClass().getSimpleName() + 122 " is invalid for opcode " + opcode.name + ". This opcode does not reference an item"); 123 } 124 } 125 } 126 } 127