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.generic;
20
21 import java.io.DataOutputStream;
22 import java.io.IOException;
23
24 import org.apache.bcel.Const;
25 import org.apache.bcel.ExceptionConst;
26 import org.apache.bcel.classfile.ConstantInvokeDynamic;
27 import org.apache.bcel.classfile.ConstantNameAndType;
28 import org.apache.bcel.classfile.ConstantPool;
29 import org.apache.bcel.util.ByteSequence;
30
31 /**
32 * Class for INVOKEDYNAMIC. Not an instance of InvokeInstruction, since that class expects to be able to get the class
33 * of the method. Ignores the bootstrap mechanism entirely.
34 *
35 * @see <a href="https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-6.html#jvms-6.5.invokedynamic"> The
36 * invokedynamic instruction in The Java Virtual Machine Specification</a>
37 * @since 6.0
38 */
39 public class INVOKEDYNAMIC extends InvokeInstruction {
40
41 /**
42 * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
43 */
44 INVOKEDYNAMIC() {
45 }
46
47 public INVOKEDYNAMIC(final int index) {
48 super(Const.INVOKEDYNAMIC, index);
49 }
50
51 /**
52 * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
53 * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last.
54 *
55 * @param v Visitor object
56 */
57 @Override
58 public void accept(final Visitor v) {
59 v.visitExceptionThrower(this);
60 v.visitTypedInstruction(this);
61 v.visitStackConsumer(this);
62 v.visitStackProducer(this);
63 v.visitLoadClass(this);
64 v.visitCPInstruction(this);
65 v.visitFieldOrMethod(this);
66 v.visitInvokeInstruction(this);
67 v.visitINVOKEDYNAMIC(this);
68 }
69
70 /**
71 * Dump instruction as byte code to stream out.
72 *
73 * @param out Output stream
74 */
75 @Override
76 public void dump(final DataOutputStream out) throws IOException {
77 out.writeByte(super.getOpcode());
78 out.writeShort(super.getIndex());
79 out.writeByte(0);
80 out.writeByte(0);
81 }
82
83 /**
84 * Override the parent method because our class name is held elsewhere.
85 *
86 * Note: Contrary to this method's name it does not return the class name of the invoke target; rather it returns the
87 * name of the method that will be used to invoke the Lambda method generated by this invoke dynamic instruction.
88 */
89 @Override
90 public String getClassName(final ConstantPoolGen cpg) {
91 final ConstantPool cp = cpg.getConstantPool();
92 final ConstantInvokeDynamic cid = cp.getConstant(super.getIndex(), Const.CONSTANT_InvokeDynamic, ConstantInvokeDynamic.class);
93 return cp.getConstant(cid.getNameAndTypeIndex(), ConstantNameAndType.class).getName(cp);
94 }
95
96 @Override
97 public Class<?>[] getExceptions() {
98 return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_INTERFACE_METHOD_RESOLUTION, ExceptionConst.UNSATISFIED_LINK_ERROR,
99 ExceptionConst.ABSTRACT_METHOD_ERROR, ExceptionConst.ILLEGAL_ACCESS_ERROR, ExceptionConst.INCOMPATIBLE_CLASS_CHANGE_ERROR);
100 }
101
102 /**
103 * Since InvokeDynamic doesn't refer to a reference type, just return {@link Object}, as that is the only type we can
104 * say for sure the reference will be.
105 *
106 * @param cpg the ConstantPoolGen used to create the instruction
107 * @return an ObjectType for {@link Object}
108 * @since 6.1
109 */
110 @Override
111 public ReferenceType getReferenceType(final ConstantPoolGen cpg) {
112 return new ObjectType(Object.class.getName());
113 }
114
115 /**
116 * Reads needed data (i.e., index) from file.
117 */
118 @Override
119 protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {
120 super.initFromFile(bytes, wide);
121 super.setLength(5);
122 bytes.readByte(); // Skip 0 byte
123 bytes.readByte(); // Skip 0 byte
124 }
125
126 }