1 /*
2  * Copyright 2013, Google Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are
7  * met:
8  *
9  *     * Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  *     * Redistributions in binary form must reproduce the above
12  * copyright notice, this list of conditions and the following disclaimer
13  * in the documentation and/or other materials provided with the
14  * distribution.
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16  * contributors may be used to endorse or promote products derived from
17  * this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 package org.jf.dexlib2.writer.builder;
33 
34 import com.google.common.collect.Maps;
35 import org.jf.dexlib2.writer.DexWriter;
36 import org.jf.dexlib2.writer.StringSection;
37 
38 import javax.annotation.Nonnull;
39 import javax.annotation.Nullable;
40 import java.util.Collection;
41 import java.util.Map.Entry;
42 import java.util.concurrent.ConcurrentMap;
43 
44 class BuilderStringPool implements StringSection<BuilderStringReference, BuilderStringReference> {
45     @Nonnull private final ConcurrentMap<String, BuilderStringReference> internedItems = Maps.newConcurrentMap();
46 
internString(@onnull String string)47     @Nonnull BuilderStringReference internString(@Nonnull String string) {
48         BuilderStringReference ret = internedItems.get(string);
49         if (ret != null) {
50             return ret;
51         }
52         BuilderStringReference stringReference = new BuilderStringReference(string);
53         ret = internedItems.putIfAbsent(string, stringReference);
54         return ret==null?stringReference:ret;
55     }
56 
internNullableString(@ullable String string)57     @Nullable BuilderStringReference internNullableString(@Nullable String string) {
58         if (string == null) {
59             return null;
60         }
61         return internString(string);
62     }
63 
getNullableItemIndex(@ullable BuilderStringReference key)64     @Override public int getNullableItemIndex(@Nullable BuilderStringReference key) {
65         return key==null?DexWriter.NO_INDEX:key.index;
66     }
67 
getItemIndex(@onnull BuilderStringReference key)68     @Override public int getItemIndex(@Nonnull BuilderStringReference key) {
69         return key.index;
70     }
71 
hasJumboIndexes()72     @Override public boolean hasJumboIndexes() {
73         return internedItems.size() > 65536;
74     }
75 
getItems()76     @Nonnull @Override public Collection<? extends Entry<? extends BuilderStringReference, Integer>> getItems() {
77         return new BuilderMapEntryCollection<BuilderStringReference>(internedItems.values()) {
78             @Override protected int getValue(@Nonnull BuilderStringReference key) {
79                 return key.index;
80             }
81 
82             @Override protected int setValue(@Nonnull BuilderStringReference key, int value) {
83                 int prev = key.index;
84                 key.index = value;
85                 return prev;
86             }
87         };
88     }
89 }
90