1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one or more
3  * contributor license agreements.  See the NOTICE file distributed with
4  * this work for additional information regarding copyright ownership.
5  * The ASF licenses this file to You under the Apache License, Version 2.0
6  * (the "License"); you may not use this file except in compliance with
7  * the License.  You may obtain a copy of the License at
8  *
9  *      http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  */
17 
18 package org.apache.bcel.classfile;
19 
20 import java.io.DataInput;
21 import java.io.DataOutputStream;
22 import java.io.IOException;
23 
24 import org.apache.bcel.Const;
25 
26 /**
27  * This class represents a BootstrapMethods attribute.
28  *
29  * @see <a href="http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.7.23">
30  * The class File Format : The BootstrapMethods Attribute</a>
31  * @since 6.0
32  */
33 public class BootstrapMethods extends Attribute {
34 
35     private BootstrapMethod[] bootstrap_methods;  // TODO this could be made final (setter is not used)
36 
37     /**
38      * Initialize from another object. Note that both objects use the same
39      * references (shallow copy). Use clone() for a physical copy.
40      */
BootstrapMethods(final BootstrapMethods c)41     public BootstrapMethods(final BootstrapMethods c) {
42         this(c.getNameIndex(), c.getLength(), c.getBootstrapMethods(), c.getConstantPool());
43     }
44 
45 
46     /**
47      * @param name_index Index in constant pool to CONSTANT_Utf8
48      * @param length Content length in bytes
49      * @param bootstrap_methods array of bootstrap methods
50      * @param constant_pool Array of constants
51      */
BootstrapMethods(final int name_index, final int length, final BootstrapMethod[] bootstrap_methods, final ConstantPool constant_pool)52     public BootstrapMethods(final int name_index, final int length, final BootstrapMethod[] bootstrap_methods, final ConstantPool constant_pool) {
53         super(Const.ATTR_BOOTSTRAP_METHODS, name_index, length, constant_pool);
54         this.bootstrap_methods = bootstrap_methods;
55     }
56 
57     /**
58      * Construct object from Input stream.
59      *
60      * @param name_index Index in constant pool to CONSTANT_Utf8
61      * @param length Content length in bytes
62      * @param input Input stream
63      * @param constant_pool Array of constants
64      * @throws IOException
65      */
BootstrapMethods(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool)66     BootstrapMethods(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool) throws IOException {
67         this(name_index, length, (BootstrapMethod[]) null, constant_pool);
68 
69         final int num_bootstrap_methods = input.readUnsignedShort();
70         bootstrap_methods = new BootstrapMethod[num_bootstrap_methods];
71         for (int i = 0; i < num_bootstrap_methods; i++) {
72             bootstrap_methods[i] = new BootstrapMethod(input);
73         }
74     }
75 
76     /**
77      * @return array of bootstrap method "records"
78      */
getBootstrapMethods()79     public final BootstrapMethod[] getBootstrapMethods() {
80         return bootstrap_methods;
81     }
82 
83     /**
84      * @param bootstrap_methods the array of bootstrap methods
85      */
setBootstrapMethods(final BootstrapMethod[] bootstrap_methods)86     public final void setBootstrapMethods(final BootstrapMethod[] bootstrap_methods) {
87         this.bootstrap_methods = bootstrap_methods;
88     }
89 
90     /**
91      * @param v Visitor object
92      */
93     @Override
accept(final Visitor v)94     public void accept(final Visitor v) {
95         v.visitBootstrapMethods(this);
96     }
97 
98     /**
99      * @return deep copy of this attribute
100      */
101     @Override
copy(final ConstantPool _constant_pool)102     public BootstrapMethods copy(final ConstantPool _constant_pool) {
103         final BootstrapMethods c = (BootstrapMethods) clone();
104         c.bootstrap_methods = new BootstrapMethod[bootstrap_methods.length];
105 
106         for (int i = 0; i < bootstrap_methods.length; i++) {
107             c.bootstrap_methods[i] = bootstrap_methods[i].copy();
108         }
109         c.setConstantPool(_constant_pool);
110         return c;
111     }
112 
113     /**
114      * Dump bootstrap methods attribute to file stream in binary format.
115      *
116      * @param file Output file stream
117      * @throws IOException
118      */
119     @Override
dump(final DataOutputStream file)120     public final void dump(final DataOutputStream file) throws IOException {
121         super.dump(file);
122 
123         file.writeShort(bootstrap_methods.length);
124         for (final BootstrapMethod bootstrap_method : bootstrap_methods) {
125             bootstrap_method.dump(file);
126         }
127     }
128 
129     /**
130      * @return String representation.
131      */
132     @Override
toString()133     public final String toString() {
134         final StringBuilder buf = new StringBuilder();
135         buf.append("BootstrapMethods(");
136         buf.append(bootstrap_methods.length);
137         buf.append("):\n");
138         for (int i = 0; i < bootstrap_methods.length; i++) {
139             buf.append("  ").append(i).append(": ");
140             buf.append(bootstrap_methods[i].toString(super.getConstantPool())).append("\n");
141         }
142         return buf.toString();
143     }
144 }
145