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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.generic;
19  
20  import java.io.DataOutputStream;
21  import java.io.IOException;
22  
23  import org.apache.bcel.util.ByteSequence;
24  
25  /**
26   * LOOKUPSWITCH - Switch with unordered set of values
27   *
28   * @version $Id: LOOKUPSWITCH.html 1021978 2017-12-09 17:38:21Z ggregory $
29   * @see SWITCH
30   */
31  public class LOOKUPSWITCH extends Select {
32  
33      /**
34       * Empty constructor needed for Instruction.readInstruction.
35       * Not to be used otherwise.
36       */
37      LOOKUPSWITCH() {
38      }
39  
40  
41      public LOOKUPSWITCH(final int[] match, final InstructionHandle[] targets, final InstructionHandle defaultTarget) {
42          super(org.apache.bcel.Const.LOOKUPSWITCH, match, targets, defaultTarget);
43          /* alignment remainder assumed 0 here, until dump time. */
44          final short _length = (short) (9 + getMatch_length() * 8);
45          super.setLength(_length);
46          setFixed_length(_length);
47      }
48  
49  
50      /**
51       * Dump instruction as byte code to stream out.
52       * @param out Output stream
53       */
54      @Override
55      public void dump( final DataOutputStream out ) throws IOException {
56          super.dump(out);
57          final int _match_length = getMatch_length();
58          out.writeInt(_match_length); // npairs
59          for (int i = 0; i < _match_length; i++) {
60              out.writeInt(super.getMatch(i)); // match-offset pairs
61              out.writeInt(setIndices(i, getTargetOffset(super.getTarget(i))));
62          }
63      }
64  
65  
66      /**
67       * Read needed data (e.g. index) from file.
68       */
69      @Override
70      protected void initFromFile( final ByteSequence bytes, final boolean wide ) throws IOException {
71          super.initFromFile(bytes, wide); // reads padding
72          final int _match_length = bytes.readInt();
73          setMatch_length(_match_length);
74          final short _fixed_length = (short) (9 + _match_length * 8);
75          setFixed_length(_fixed_length);
76          final short _length = (short) (_match_length + super.getPadding());
77          super.setLength(_length);
78          super.setMatches(new int[_match_length]);
79          super.setIndices(new int[_match_length]);
80          super.setTargets(new InstructionHandle[_match_length]);
81          for (int i = 0; i < _match_length; i++) {
82              super.setMatch(i, bytes.readInt());
83              super.setIndices(i, bytes.readInt());
84          }
85      }
86  
87  
88      /**
89       * Call corresponding visitor method(s). The order is:
90       * Call visitor methods of implemented interfaces first, then
91       * call methods according to the class hierarchy in descending order,
92       * i.e., the most specific visitXXX() call comes last.
93       *
94       * @param v Visitor object
95       */
96      @Override
97      public void accept( final Visitor v ) {
98          v.visitVariableLengthInstruction(this);
99          v.visitStackConsumer(this);
100         v.visitBranchInstruction(this);
101         v.visitSelect(this);
102         v.visitLOOKUPSWITCH(this);
103     }
104 }