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 */
017package org.apache.bcel.verifier.structurals;
018
019import org.apache.bcel.generic.InstructionHandle;
020import org.apache.bcel.generic.ObjectType;
021
022/**
023 * This class represents an exception handler; that is, an ObjectType representing a subclass of {@link Throwable} and
024 * the instruction the handler starts off (represented by an InstructionContext).
025 */
026public class ExceptionHandler {
027
028    static final ExceptionHandler[] EMPTY_ARRAY = {};
029
030    /** The type of the exception to catch. NULL means ANY. */
031    private final ObjectType catchType;
032
033    /** The InstructionHandle where the handling begins. */
034    private final InstructionHandle handlerPc;
035
036    /** Leave instance creation to JustIce. */
037    ExceptionHandler(final ObjectType catchType, final InstructionHandle handlerPc) {
038        this.catchType = catchType;
039        this.handlerPc = handlerPc;
040    }
041
042    /**
043     * Returns the type of the exception that's handled. <B>'null' means 'ANY'.</B>
044     */
045    public ObjectType getExceptionType() {
046        return catchType;
047    }
048
049    /**
050     * Returns the InstructionHandle where the handler starts off.
051     */
052    public InstructionHandle getHandlerStart() {
053        return handlerPc;
054    }
055}