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.util.ByteSequence;
25
26 /**
27 * LOOKUPSWITCH - Switch with unordered set of values
28 *
29 * @see SWITCH
30 */
31 public class LOOKUPSWITCH extends Select {
32
33 /**
34 * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
35 */
36 LOOKUPSWITCH() {
37 }
38
39 public LOOKUPSWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle defaultTarget) {
40 super(org.apache.bcel.Const.LOOKUPSWITCH, match, targets, defaultTarget);
41 /* alignment remainder assumed 0 here, until dump time. */
42 final short length = (short) (9 + getMatchLength() * 8);
43 super.setLength(length);
44 setFixedLength(length);
45 }
46
47 /**
48 * Call corresponding visitor method(s). The order is: Call visitor methods of implemented interfaces first, then call
49 * methods according to the class hierarchy in descending order, i.e., the most specific visitXXX() call comes last.
50 *
51 * @param v Visitor object
52 */
53 @Override
54 public void accept(final Visitor v) {
55 v.visitVariableLengthInstruction(this);
56 v.visitStackConsumer(this);
57 v.visitBranchInstruction(this);
58 v.visitSelect(this);
59 v.visitLOOKUPSWITCH(this);
60 }
61
62 /**
63 * Dump instruction as byte code to stream out.
64 *
65 * @param out Output stream
66 */
67 @Override
68 public void dump(final DataOutputStream out) throws IOException {
69 super.dump(out);
70 final int matchLength = getMatchLength();
71 out.writeInt(matchLength); // npairs
72 for (int i = 0; i < matchLength; i++) {
73 out.writeInt(super.getMatch(i)); // match-offset pairs
74 out.writeInt(setIndices(i, getTargetOffset(super.getTarget(i))));
75 }
76 }
77
78 /**
79 * Reads needed data (for example index) from file.
80 */
81 @Override
82 protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {
83 super.initFromFile(bytes, wide); // reads padding
84 final int matchLength = bytes.readInt();
85 setMatchLength(matchLength);
86 final short fixedLength = (short) (9 + matchLength * 8);
87 setFixedLength(fixedLength);
88 final short length = (short) (matchLength + super.getPadding());
89 super.setLength(length);
90 super.setMatches(new int[matchLength]);
91 super.setIndices(new int[matchLength]);
92 super.setTargets(new InstructionHandle[matchLength]);
93 for (int i = 0; i < matchLength; i++) {
94 super.setMatch(i, bytes.readInt());
95 super.setIndices(i, bytes.readInt());
96 }
97 }
98 }