1/*
2 * Copyright (C) 2008 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
17package com.android.dexgen.dex.file;
18
19import com.android.dexgen.rop.cst.CstType;
20import com.android.dexgen.rop.cst.CstUtf8;
21import com.android.dexgen.rop.type.Prototype;
22import com.android.dexgen.rop.type.StdTypeList;
23import com.android.dexgen.rop.type.Type;
24import com.android.dexgen.util.AnnotatedOutput;
25import com.android.dexgen.util.Hex;
26
27/**
28 * Representation of a method prototype reference inside a Dalvik file.
29 */
30public final class ProtoIdItem extends IndexedItem {
31    /** size of instances when written out to a file, in bytes */
32    public static final int WRITE_SIZE = 12;
33
34    /** {@code non-null;} the wrapped prototype */
35    private final Prototype prototype;
36
37    /** {@code non-null;} the short-form of the prototype */
38    private final CstUtf8 shortForm;
39
40    /**
41     * {@code null-ok;} the list of parameter types or {@code null} if this
42     * prototype has no parameters
43     */
44    private TypeListItem parameterTypes;
45
46    /**
47     * Constructs an instance.
48     *
49     * @param prototype {@code non-null;} the constant for the prototype
50     */
51    public ProtoIdItem(Prototype prototype) {
52        if (prototype == null) {
53            throw new NullPointerException("prototype == null");
54        }
55
56        this.prototype = prototype;
57        this.shortForm = makeShortForm(prototype);
58
59        StdTypeList parameters = prototype.getParameterTypes();
60        this.parameterTypes = (parameters.size() == 0) ? null
61            : new TypeListItem(parameters);
62    }
63
64    /**
65     * Creates the short-form of the given prototype.
66     *
67     * @param prototype {@code non-null;} the prototype
68     * @return {@code non-null;} the short form
69     */
70    private static CstUtf8 makeShortForm(Prototype prototype) {
71        StdTypeList parameters = prototype.getParameterTypes();
72        int size = parameters.size();
73        StringBuilder sb = new StringBuilder(size + 1);
74
75        sb.append(shortFormCharFor(prototype.getReturnType()));
76
77        for (int i = 0; i < size; i++) {
78            sb.append(shortFormCharFor(parameters.getType(i)));
79        }
80
81        return new CstUtf8(sb.toString());
82    }
83
84    /**
85     * Gets the short-form character for the given type.
86     *
87     * @param type {@code non-null;} the type
88     * @return the corresponding short-form character
89     */
90    private static char shortFormCharFor(Type type) {
91        char descriptorChar = type.getDescriptor().charAt(0);
92
93        if (descriptorChar == '[') {
94            return 'L';
95        }
96
97        return descriptorChar;
98    }
99
100    /** {@inheritDoc} */
101    @Override
102    public ItemType itemType() {
103        return ItemType.TYPE_PROTO_ID_ITEM;
104    }
105
106    /** {@inheritDoc} */
107    @Override
108    public int writeSize() {
109        return WRITE_SIZE;
110    }
111
112    /** {@inheritDoc} */
113    @Override
114    public void addContents(DexFile file) {
115        StringIdsSection stringIds = file.getStringIds();
116        TypeIdsSection typeIds = file.getTypeIds();
117        MixedItemSection typeLists = file.getTypeLists();
118
119        typeIds.intern(prototype.getReturnType());
120        stringIds.intern(shortForm);
121
122        if (parameterTypes != null) {
123            parameterTypes = typeLists.intern(parameterTypes);
124        }
125    }
126
127    /** {@inheritDoc} */
128    @Override
129    public void writeTo(DexFile file, AnnotatedOutput out) {
130        int shortyIdx = file.getStringIds().indexOf(shortForm);
131        int returnIdx = file.getTypeIds().indexOf(prototype.getReturnType());
132        int paramsOff = OffsettedItem.getAbsoluteOffsetOr0(parameterTypes);
133
134        if (out.annotates()) {
135            StringBuilder sb = new StringBuilder();
136            sb.append(prototype.getReturnType().toHuman());
137            sb.append(" proto(");
138
139            StdTypeList params = prototype.getParameterTypes();
140            int size = params.size();
141
142            for (int i = 0; i < size; i++) {
143                if (i != 0) {
144                    sb.append(", ");
145                }
146                sb.append(params.getType(i).toHuman());
147            }
148
149            sb.append(")");
150            out.annotate(0, indexString() + ' ' + sb.toString());
151            out.annotate(4, "  shorty_idx:      " + Hex.u4(shortyIdx) +
152                    " // " + shortForm.toQuoted());
153            out.annotate(4, "  return_type_idx: " + Hex.u4(returnIdx) +
154                    " // " + prototype.getReturnType().toHuman());
155            out.annotate(4, "  parameters_off:  " + Hex.u4(paramsOff));
156        }
157
158        out.writeInt(shortyIdx);
159        out.writeInt(returnIdx);
160        out.writeInt(paramsOff);
161    }
162}
163