1/*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5/*
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements.  See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License.  You may obtain a copy of the License at
12 *
13 *      http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 */
21
22package com.sun.org.apache.bcel.internal.generic;
23
24import java.io.*;
25
26/**
27 * JSR - Jump to subroutine
28 *
29 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
30 */
31public class JSR extends JsrInstruction implements VariableLengthInstruction {
32  /**
33   * Empty constructor needed for the Class.newInstance() statement in
34   * Instruction.readInstruction(). Not to be used otherwise.
35   */
36  JSR() {}
37
38  public JSR(InstructionHandle target) {
39    super(com.sun.org.apache.bcel.internal.Constants.JSR, target);
40  }
41
42  /**
43   * Dump instruction as byte code to stream out.
44   * @param out Output stream
45   */
46  public void dump(DataOutputStream out) throws IOException {
47    index = getTargetOffset();
48    if(opcode == com.sun.org.apache.bcel.internal.Constants.JSR)
49      super.dump(out);
50    else { // JSR_W
51      index = getTargetOffset();
52      out.writeByte(opcode);
53      out.writeInt(index);
54    }
55  }
56
57  protected int updatePosition(int offset, int max_offset) {
58    int i = getTargetOffset(); // Depending on old position value
59
60    position += offset; // Position may be shifted by preceding expansions
61
62    if(Math.abs(i) >= (32767 - max_offset)) { // to large for short (estimate)
63      opcode  = com.sun.org.apache.bcel.internal.Constants.JSR_W;
64      length = 5;
65      return 2; // 5 - 3
66    }
67
68    return 0;
69  }
70
71  /**
72   * Call corresponding visitor method(s). The order is:
73   * Call visitor methods of implemented interfaces first, then
74   * call methods according to the class hierarchy in descending order,
75   * i.e., the most specific visitXXX() call comes last.
76   *
77   * @param v Visitor object
78   */
79  public void accept(Visitor v) {
80    v.visitStackProducer(this);
81    v.visitVariableLengthInstruction(this);
82    v.visitBranchInstruction(this);
83    v.visitJsrInstruction(this);
84    v.visitJSR(this);
85  }
86}
87