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
44 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
45 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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
61 /**
62 * INSTANCEOF - Determine if object is of given type
63 * <PRE>Stack: ..., objectref -> ..., result</PRE>
64 *
65 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
66 */
67 public class INSTANCEOF extends CPInstruction
68 implements LoadClass, ExceptionThrower, StackProducer, StackConsumer {
69 /**
70 * Empty constructor needed for the Class.newInstance() statement in
71 * Instruction.readInstruction(). Not to be used otherwise.
72 */
73 INSTANCEOF() {}
74
75 public INSTANCEOF(int index) {
76 super(com.sun.org.apache.bcel.internal.Constants.INSTANCEOF, index);
77 }
78
79 public Class[] getExceptions() {
80 return com.sun.org.apache.bcel.internal.ExceptionConstants.EXCS_CLASS_AND_INTERFACE_RESOLUTION;
81 }
82
83 public ObjectType getLoadClassType(ConstantPoolGen cpg) {
84 Type t = getType(cpg);
85
86 if(t instanceof ArrayType)
87 t = ((ArrayType) t).getBasicType();
88
89 return (t instanceof ObjectType)? (ObjectType) t : null;
90 }
91
92 /**
93 * Call corresponding visitor method(s). The order is:
94 * Call visitor methods of implemented interfaces first, then
95 * call methods according to the class hierarchy in descending order,
96 * i.e., the most specific visitXXX() call comes last.
97 *
98 * @param v Visitor object
99 */
100 public void accept(Visitor v) {
101 v.visitLoadClass(this);
102 v.visitExceptionThrower(this);
103 v.visitStackProducer(this);
104 v.visitStackConsumer(this);
105 v.visitTypedInstruction(this);
106 v.visitCPInstruction(this);
107 v.visitINSTANCEOF(this);
108 }
109 }