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