ArrayProto.java revision 39e4d4487e20041700f036a58a4dd7fb50e954bf 
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.
15 *     * Neither the name of Google Inc. nor the names of its
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
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32package org.jf.dexlib2.analysis;
33
34import com.google.common.base.Strings;
35import org.jf.dexlib2.util.TypeUtils;
36import org.jf.util.ExceptionWithContext;
37
38import javax.annotation.Nonnull;
39import javax.annotation.Nullable;
40
41public class ArrayProto implements TypeProto {
42    protected final ClassPath classPath;
43    protected final int dimensions;
44    protected final String elementType;
45
46    public ArrayProto(@Nonnull ClassPath classPath, @Nonnull String type) {
47        this.classPath = classPath;
48        int i=0;
49        while (type.charAt(i) == '[') {
50            i++;
51            if (i == type.length()) {
52                throw new ExceptionWithContext("Invalid array type: %s", type);
53            }
54        }
55
56        dimensions = i;
57        elementType = type.substring(i);
58    }
59
60    @Override public String toString() { return getType(); }
61    @Nonnull @Override public ClassPath getClassPath() { return classPath; }
62    @Nonnull @Override public String getType() { return makeArrayType(elementType, dimensions); }
63    @Nonnull public String getElementType() { return elementType; }
64    @Override public boolean isInterface() { return false; }
65
66    @Override public boolean implementsInterface(@Nonnull String iface) {
67        return iface.equals("Ljava/lang/Cloneable;") || iface.equals("Ljava/io/Serializable;");
68    }
69
70    @Nullable @Override
71    public String getSuperclass() {
72        return "Ljava/lang/Object;";
73    }
74
75    @Nonnull @Override
76    public TypeProto getCommonSuperclass(@Nonnull TypeProto other) {
77        if (other instanceof ArrayProto) {
78            if (TypeUtils.isPrimitiveType(getElementType()) ||
79                    TypeUtils.isPrimitiveType(((ArrayProto)other).getElementType())) {
80                if (dimensions == ((ArrayProto)other).dimensions &&
81                        getElementType().equals(((ArrayProto)other).getElementType())) {
82                    return this;
83                }
84                return classPath.getClass("Ljava/lang/Object;");
85            }
86
87            if (dimensions == ((ArrayProto)other).dimensions) {
88                TypeProto thisClass = classPath.getClass(elementType);
89                TypeProto otherClass = classPath.getClass(((ArrayProto)other).elementType);
90                TypeProto mergedClass = thisClass.getCommonSuperclass(otherClass);
91                if (thisClass == mergedClass) {
92                    return this;
93                }
94                if (otherClass == mergedClass) {
95                    return other;
96                }
97                return classPath.getClass(makeArrayType(mergedClass.getType(), dimensions));
98            }
99
100            int dimensions = Math.min(this.dimensions, ((ArrayProto)other).dimensions);
101            return classPath.getClass(makeArrayType("Ljava/lang/Object;", dimensions));
102        }
103
104        if (other instanceof ClassProto) {
105            try {
106                if (other.isInterface()) {
107                    if (implementsInterface(other.getType())) {
108                        return other;
109                    }
110                }
111            } catch (UnresolvedClassException ex) {
112                // ignore
113            }
114            return classPath.getClass("Ljava/lang/Object;");
115        }
116
117        // otherwise, defer to the other class' getCommonSuperclass
118        return other.getCommonSuperclass(this);
119    }
120
121    private static final String BRACKETS = Strings.repeat("[", 256);
122
123    @Nonnull
124    private static String makeArrayType(@Nonnull String elementType, int dimensions) {
125        return BRACKETS.substring(0, dimensions) + elementType;
126    }
127}
128