1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.dx.dex.file; 18 19 import com.android.dx.rop.cst.Constant; 20 import com.android.dx.rop.cst.CstNat; 21 import com.android.dx.rop.cst.CstString; 22 import com.android.dx.util.AnnotatedOutput; 23 import com.android.dx.util.Hex; 24 25 import java.util.Collection; 26 import java.util.TreeMap; 27 28 /** 29 * Strings list section of a {@code .dex} file. 30 */ 31 public final class StringIdsSection 32 extends UniformItemSection { 33 /** 34 * {@code non-null;} map from string constants to {@link 35 * StringIdItem} instances 36 */ 37 private final TreeMap<CstString, StringIdItem> strings; 38 39 /** 40 * Constructs an instance. The file offset is initially unknown. 41 * 42 * @param file {@code non-null;} file that this instance is part of 43 */ 44 public StringIdsSection(DexFile file) { 45 super("string_ids", file, 4); 46 47 strings = new TreeMap<CstString, StringIdItem>(); 48 } 49 50 /** {@inheritDoc} */ 51 @Override 52 public Collection<? extends Item> items() { 53 return strings.values(); 54 } 55 56 /** {@inheritDoc} */ 57 @Override 58 public IndexedItem get(Constant cst) { 59 if (cst == null) { 60 throw new NullPointerException("cst == null"); 61 } 62 63 throwIfNotPrepared(); 64 65 IndexedItem result = strings.get((CstString) cst); 66 67 if (result == null) { 68 throw new IllegalArgumentException("not found"); 69 } 70 71 return result; 72 } 73 74 /** 75 * Writes the portion of the file header that refers to this instance. 76 * 77 * @param out {@code non-null;} where to write 78 */ 79 public void writeHeaderPart(AnnotatedOutput out) { 80 throwIfNotPrepared(); 81 82 int sz = strings.size(); 83 int offset = (sz == 0) ? 0 : getFileOffset(); 84 85 if (out.annotates()) { 86 out.annotate(4, "string_ids_size: " + Hex.u4(sz)); 87 out.annotate(4, "string_ids_off: " + Hex.u4(offset)); 88 } 89 90 out.writeInt(sz); 91 out.writeInt(offset); 92 } 93 94 /** 95 * Interns an element into this instance. 96 * 97 * @param string {@code non-null;} the string to intern, as a regular Java 98 * {@code String} 99 * @return {@code non-null;} the interned string 100 */ 101 public StringIdItem intern(String string) { 102 return intern(new StringIdItem(new CstString(string))); 103 } 104 105 /** 106 * Interns an element into this instance. 107 * 108 * @param string {@code non-null;} the string to intern, as a constant 109 * @return {@code non-null;} the interned string 110 */ 111 public StringIdItem intern(CstString string) { 112 return intern(new StringIdItem(string)); 113 } 114 115 /** 116 * Interns an element into this instance. 117 * 118 * @param string {@code non-null;} the string to intern 119 * @return {@code non-null;} the interned string 120 */ 121 public StringIdItem intern(StringIdItem string) { 122 if (string == null) { 123 throw new NullPointerException("string == null"); 124 } 125 126 throwIfPrepared(); 127 128 CstString value = string.getValue(); 129 StringIdItem already = strings.get(value); 130 131 if (already != null) { 132 return already; 133 } 134 135 strings.put(value, string); 136 return string; 137 } 138 139 /** 140 * Interns the components of a name-and-type into this instance. 141 * 142 * @param nat {@code non-null;} the name-and-type 143 */ 144 public void intern(CstNat nat) { 145 intern(nat.getName()); 146 intern(nat.getDescriptor()); 147 } 148 149 /** 150 * Gets the index of the given string, which must have been added 151 * to this instance. 152 * 153 * @param string {@code non-null;} the string to look up 154 * @return {@code >= 0;} the string's index 155 */ 156 public int indexOf(CstString string) { 157 if (string == null) { 158 throw new NullPointerException("string == null"); 159 } 160 161 throwIfNotPrepared(); 162 163 StringIdItem s = strings.get(string); 164 165 if (s == null) { 166 throw new IllegalArgumentException("not found"); 167 } 168 169 return s.getIndex(); 170 } 171 172 /** {@inheritDoc} */ 173 @Override 174 protected void orderItems() { 175 int idx = 0; 176 177 for (StringIdItem s : strings.values()) { 178 s.setIndex(idx); 179 idx++; 180 } 181 } 182 } 183