1 package org.apache.bcel.generic;
2
3 /* ====================================================================
4 * The Apache Software License, Version 1.1
5 *
6 * Copyright (c) 2001 The Apache Software Foundation. All rights
7 * reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
19 * distribution.
20 *
21 * 3. The end-user documentation included with the redistribution,
22 * if any, must include the following acknowledgment:
23 * "This product includes software developed by the
24 * Apache Software Foundation (http://www.apache.org/)."
25 * Alternately, this acknowledgment may appear in the software itself,
26 * if and wherever such third-party acknowledgments normally appear.
27 *
28 * 4. The names "Apache" and "Apache Software Foundation" and
29 * "Apache BCEL" must not be used to endorse or promote products
30 * derived from this software without prior written permission. For
31 * written permission, please contact apache@apache.org.
32 *
33 * 5. Products derived from this software may not be called "Apache",
34 * "Apache BCEL", nor may "Apache" appear in their name, without
35 * prior written permission of the Apache Software Foundation.
36 *
37 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
40 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
41 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
44 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
45 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
46 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
47 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48 * SUCH DAMAGE.
49 * ====================================================================
50 *
51 * This software consists of voluntary contributions made by many
52 * individuals on behalf of the Apache Software Foundation. For more
53 * information on the Apache Software Foundation, please see
54 * <http://www.apache.org/>.
55 */
56 import org.apache.bcel.ExceptionConstants;
57 /***
58 * CHECKCAST - Check whether object is of given type
59 * <PRE>Stack: ..., objectref -> ..., objectref</PRE>
60 *
61 * @version $Id: CHECKCAST.java,v 1.1.1.1 2001/10/29 20:00:07 jvanzyl Exp $
62 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
63 */
64 public class CHECKCAST extends CPInstruction
65 implements LoadClass, ExceptionThrower, StackProducer, StackConsumer {
66 /***
67 * Empty constructor needed for the Class.newInstance() statement in
68 * Instruction.readInstruction(). Not to be used otherwise.
69 */
70 CHECKCAST() {}
71
72 /*** Check whether object is of given type
73 * @param n index to class in constant pool
74 */
75 public CHECKCAST(int index) {
76 super(org.apache.bcel.Constants.CHECKCAST, index);
77 }
78
79 /*** @return exceptions this instruction may cause
80 */
81 public Class[] getExceptions() {
82 Class[] cs = new Class[1 + ExceptionConstants.EXCS_CLASS_AND_INTERFACE_RESOLUTION.length];
83
84 System.arraycopy(ExceptionConstants.EXCS_CLASS_AND_INTERFACE_RESOLUTION, 0,
85 cs, 0, ExceptionConstants.EXCS_CLASS_AND_INTERFACE_RESOLUTION.length);
86 cs[ExceptionConstants.EXCS_CLASS_AND_INTERFACE_RESOLUTION.length] =
87 ExceptionConstants.CLASS_CAST_EXCEPTION;
88 return cs;
89 }
90
91 public ObjectType getLoadClassType(ConstantPoolGen cpg) {
92 Type t = getType(cpg);
93
94 if(t instanceof ArrayType)
95 t = ((ArrayType) t).getBasicType();
96
97 return (t instanceof ObjectType)? (ObjectType) t : null;
98 }
99
100 /***
101 * Call corresponding visitor method(s). The order is:
102 * Call visitor methods of implemented interfaces first, then
103 * call methods according to the class hierarchy in descending order,
104 * i.e., the most specific visitXXX() call comes last.
105 *
106 * @param v Visitor object
107 */
108 public void accept(Visitor v) {
109 v.visitLoadClass(this);
110 v.visitExceptionThrower(this);
111 v.visitStackProducer(this);
112 v.visitStackConsumer(this);
113 v.visitTypedInstruction(this);
114 v.visitCPInstruction(this);
115 v.visitCHECKCAST(this);
116 }
117 }
This page was automatically generated by Maven