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 * CHECKCAST - Check whether object is of given type 28 * <PRE>Stack: ..., objectref -> ..., objectref</PRE> 29 * 30 * @version $Id$ 31 */ 32 public class CHECKCAST extends CPInstruction implements LoadClass, ExceptionThrower, StackProducer, 33 StackConsumer { 34 35 /** 36 * Empty constructor needed for Instruction.readInstruction. 37 * Not to be used otherwise. 38 */ CHECKCAST()39 CHECKCAST() { 40 } 41 42 43 /** Check whether object is of given type 44 * @param index index to class in constant pool 45 */ CHECKCAST(final int index)46 public CHECKCAST(final int index) { 47 super(com.sun.org.apache.bcel.internal.Const.CHECKCAST, index); 48 } 49 50 51 /** @return exceptions this instruction may cause 52 */ 53 @Override getExceptions()54 public Class<?>[] getExceptions() { 55 return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_CLASS_AND_INTERFACE_RESOLUTION, 56 ExceptionConst.CLASS_CAST_EXCEPTION); 57 } 58 59 60 @Override getLoadClassType( final ConstantPoolGen cpg )61 public ObjectType getLoadClassType( final ConstantPoolGen cpg ) { 62 Type t = getType(cpg); 63 if (t instanceof ArrayType) { 64 t = ((ArrayType) t).getBasicType(); 65 } 66 return (t instanceof ObjectType) ? (ObjectType) t : null; 67 } 68 69 70 /** 71 * Call corresponding visitor method(s). The order is: 72 * Call visitor methods of implemented interfaces first, then 73 * call methods according to the class hierarchy in descending order, 74 * i.e., the most specific visitXXX() call comes last. 75 * 76 * @param v Visitor object 77 */ 78 @Override accept( final Visitor v )79 public void accept( final Visitor v ) { 80 v.visitLoadClass(this); 81 v.visitExceptionThrower(this); 82 v.visitStackProducer(this); 83 v.visitStackConsumer(this); 84 v.visitTypedInstruction(this); 85 v.visitCPInstruction(this); 86 v.visitCHECKCAST(this); 87 } 88 } 89