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1   /*
2    * reserved comment block
3    * DO NOT REMOVE OR ALTER!
4    */
5   package com.sun.org.apache.bcel.internal.generic;
6   
7   /* ====================================================================
8    * The Apache Software License, Version 1.1
9    *
10   * Copyright (c) 2001 The Apache Software Foundation.  All rights
11   * reserved.
12   *
13   * Redistribution and use in source and binary forms, with or without
14   * modification, are permitted provided that the following conditions
15   * are met:
16   *
17   * 1. Redistributions of source code must retain the above copyright
18   *    notice, this list of conditions and the following disclaimer.
19   *
20   * 2. Redistributions in binary form must reproduce the above copyright
21   *    notice, this list of conditions and the following disclaimer in
22   *    the documentation and/or other materials provided with the
23   *    distribution.
24   *
25   * 3. The end-user documentation included with the redistribution,
26   *    if any, must include the following acknowledgment:
27   *       "This product includes software developed by the
28   *        Apache Software Foundation (http://www.apache.org/)."
29   *    Alternately, this acknowledgment may appear in the software itself,
30   *    if and wherever such third-party acknowledgments normally appear.
31   *
32   * 4. The names "Apache" and "Apache Software Foundation" and
33   *    "Apache BCEL" must not be used to endorse or promote products
34   *    derived from this software without prior written permission. For
35   *    written permission, please contact apache@apache.org.
36   *
37   * 5. Products derived from this software may not be called "Apache",
38   *    "Apache BCEL", nor may "Apache" appear in their name, without
39   *    prior written permission of the Apache Software Foundation.
40   *
41   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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46   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
48   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
49   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
51   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52   * SUCH DAMAGE.
53   * ====================================================================
54   *
55   * This software consists of voluntary contributions made by many
56   * individuals on behalf of the Apache Software Foundation.  For more
57   * information on the Apache Software Foundation, please see
58   * <http://www.apache.org/>.
59   */
60  import com.sun.org.apache.bcel.internal.Constants;
61  import com.sun.org.apache.bcel.internal.ExceptionConstants;
62  
63  /**
64   * Super class for the xRETURN family of instructions.
65   *
66   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
67   */
68  public abstract class ReturnInstruction extends Instruction
69    implements ExceptionThrower, TypedInstruction, StackConsumer {
70    /**
71     * Empty constructor needed for the Class.newInstance() statement in
72     * Instruction.readInstruction(). Not to be used otherwise.
73     */
74    ReturnInstruction() {}
75  
76    /**
77     * @param opcode of instruction
78     */
79    protected ReturnInstruction(short opcode) {
80      super(opcode, (short)1);
81    }
82  
83    public Type getType() {
84      switch(opcode) {
85        case Constants.IRETURN: return Type.INT;
86        case Constants.LRETURN: return Type.LONG;
87        case Constants.FRETURN: return Type.FLOAT;
88        case Constants.DRETURN: return Type.DOUBLE;
89        case Constants.ARETURN: return Type.OBJECT;
90        case Constants.RETURN:  return Type.VOID;
91  
92      default: // Never reached
93        throw new ClassGenException("Unknown type " + opcode);
94      }
95    }
96  
97    public Class[] getExceptions() {
98      return new Class[] { ExceptionConstants.ILLEGAL_MONITOR_STATE };
99    }
100 
101   /** @return type associated with the instruction
102    */
103   public Type getType(ConstantPoolGen cp) {
104     return getType();
105   }
106 }