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 
22 package com.sun.org.apache.bcel.internal.generic;
23 
24 import com.sun.org.apache.bcel.internal.ExceptionConst;
25 
26 /**
27  * INSTANCEOF - Determine if object is of given type
28  * <PRE>Stack: ..., objectref -&gt; ..., result</PRE>
29  *
30  * @version $Id$
31  */
32 public class INSTANCEOF extends CPInstruction implements LoadClass, ExceptionThrower,
33         StackProducer, StackConsumer {
34 
35     /**
36      * Empty constructor needed for Instruction.readInstruction.
37      * Not to be used otherwise.
38      */
INSTANCEOF()39     INSTANCEOF() {
40     }
41 
42 
INSTANCEOF(final int index)43     public INSTANCEOF(final int index) {
44         super(com.sun.org.apache.bcel.internal.Const.INSTANCEOF, index);
45     }
46 
47 
48     @Override
getExceptions()49     public Class<?>[] getExceptions() {
50         return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_CLASS_AND_INTERFACE_RESOLUTION);
51     }
52 
53 
54     @Override
getLoadClassType( final ConstantPoolGen cpg )55     public ObjectType getLoadClassType( final ConstantPoolGen cpg ) {
56         Type t = getType(cpg);
57         if (t instanceof ArrayType) {
58             t = ((ArrayType) t).getBasicType();
59         }
60         return (t instanceof ObjectType) ? (ObjectType) t : null;
61     }
62 
63 
64     /**
65      * Call corresponding visitor method(s). The order is:
66      * Call visitor methods of implemented interfaces first, then
67      * call methods according to the class hierarchy in descending order,
68      * i.e., the most specific visitXXX() call comes last.
69      *
70      * @param v Visitor object
71      */
72     @Override
accept( final Visitor v )73     public void accept( final Visitor v ) {
74         v.visitLoadClass(this);
75         v.visitExceptionThrower(this);
76         v.visitStackProducer(this);
77         v.visitStackConsumer(this);
78         v.visitTypedInstruction(this);
79         v.visitCPInstruction(this);
80         v.visitINSTANCEOF(this);
81     }
82 }
83