1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * https://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.bcel.classfile;
20
21 import java.io.DataInput;
22 import java.io.IOException;
23
24 import org.apache.bcel.Const;
25
26 /**
27 * This class is derived from the abstract {@link Constant} and represents a reference to a invoke dynamic.
28 *
29 * @see Constant
30 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.4.10"> The
31 * CONSTANT_InvokeDynamic_info Structure in The Java Virtual Machine Specification</a>
32 * @since 6.0
33 */
34 public final class ConstantInvokeDynamic extends ConstantCP {
35
36 /**
37 * Initialize from another object.
38 *
39 * @param c Source to copy.
40 */
41 public ConstantInvokeDynamic(final ConstantInvokeDynamic c) {
42 this(c.getBootstrapMethodAttrIndex(), c.getNameAndTypeIndex());
43 }
44
45 /**
46 * Initialize instance from file data.
47 *
48 * @param file Input stream.
49 * @throws IOException if an I/O error occurs.
50 */
51 ConstantInvokeDynamic(final DataInput file) throws IOException {
52 this(file.readUnsignedShort(), file.readUnsignedShort());
53 }
54
55 /**
56 * Constructs a ConstantInvokeDynamic.
57 *
58 * @param bootstrapMethodAttrIndex Index to the bootstrap method.
59 * @param nameAndTypeIndex Index to the name and type.
60 */
61 public ConstantInvokeDynamic(final int bootstrapMethodAttrIndex, final int nameAndTypeIndex) {
62 super(Const.CONSTANT_InvokeDynamic, bootstrapMethodAttrIndex, nameAndTypeIndex);
63 }
64
65 /**
66 * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. I.e.,
67 * the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
68 *
69 * @param v Visitor object.
70 */
71 @Override
72 public void accept(final Visitor v) {
73 v.visitConstantInvokeDynamic(this);
74 }
75
76 /**
77 * Gets the reference (index) to bootstrap method this constant refers to.
78 *
79 * @return Reference (index) to bootstrap method this constant refers to.
80 *
81 * Note that this method is a functional duplicate of getClassIndex for use by ConstantInvokeDynamic.
82 * @since 6.0
83 */
84 public int getBootstrapMethodAttrIndex() {
85 return super.getClassIndex(); // AKA bootstrap_method_attr_index
86 }
87
88 /**
89 * @return String representation.
90 */
91 @Override
92 public String toString() {
93 return super.toString().replace("class_index", "bootstrap_method_attr_index");
94 }
95 }