001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 *  Unless required by applicable law or agreed to in writing, software
012 *  distributed under the License is distributed on an "AS IS" BASIS,
013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 *  See the License for the specific language governing permissions and
015 *  limitations under the License.
016 *
017 */
018package org.apache.bcel.verifier.structurals;
019
020import org.apache.bcel.generic.InstructionHandle;
021import org.apache.bcel.generic.ObjectType;
022
023/**
024 * This class represents an exception handler; that is, an ObjectType representing a subclass of java.lang.Throwable and
025 * the instruction the handler starts off (represented by an InstructionContext).
026 *
027 */
028public class ExceptionHandler {
029
030    static final ExceptionHandler[] EMPTY_ARRAY = {};
031
032    /** The type of the exception to catch. NULL means ANY. */
033    private final ObjectType catchType;
034
035    /** The InstructionHandle where the handling begins. */
036    private final InstructionHandle handlerPc;
037
038    /** Leave instance creation to JustIce. */
039    ExceptionHandler(final ObjectType catchType, final InstructionHandle handlerPc) {
040        this.catchType = catchType;
041        this.handlerPc = handlerPc;
042    }
043
044    /**
045     * Returns the type of the exception that's handled. <B>'null' means 'ANY'.</B>
046     */
047    public ObjectType getExceptionType() {
048        return catchType;
049    }
050
051    /**
052     * Returns the InstructionHandle where the handler starts off.
053     */
054    public InstructionHandle getHandlerStart() {
055        return handlerPc;
056    }
057}