    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;
    018
    019import org.apache.commons.lang3.ArrayUtils;
    020
    021/**
    022 * Exception constants.
    023 *
    024 * @since 6.0 (intended to replace the InstructionConstant interface)
    025 */
    026public final class ExceptionConst {
    027
    028    /**
    029     * Enum corresponding to the various Exception Class arrays, used by
    030     * {@link ExceptionConst#createExceptions(EXCS, Class...)}
    031     */
    032    public enum EXCS {
    033        EXCS_CLASS_AND_INTERFACE_RESOLUTION, EXCS_FIELD_AND_METHOD_RESOLUTION, EXCS_INTERFACE_METHOD_RESOLUTION, EXCS_STRING_RESOLUTION, EXCS_ARRAY_EXCEPTION,
    034    }
    035
    036    /**
    037     * The mother of all exceptions
    038     */
    039    public static final Class<Throwable> THROWABLE = Throwable.class;
    040
    041    /**
    042     * Super class of any run-time exception
    043     */
    044    public static final Class<RuntimeException> RUNTIME_EXCEPTION = RuntimeException.class;
    045
    046    /**
    047     * Super class of any linking exception (aka Linkage Error)
    048     */
    049    public static final Class<LinkageError> LINKING_EXCEPTION = LinkageError.class;
    050    /**
    051     * Linking Exceptions
    052     */
    053    public static final Class<ClassCircularityError> CLASS_CIRCULARITY_ERROR = ClassCircularityError.class;
    054    public static final Class<ClassFormatError> CLASS_FORMAT_ERROR = ClassFormatError.class;
    055    public static final Class<ExceptionInInitializerError> EXCEPTION_IN_INITIALIZER_ERROR = ExceptionInInitializerError.class;
    056    public static final Class<IncompatibleClassChangeError> INCOMPATIBLE_CLASS_CHANGE_ERROR = IncompatibleClassChangeError.class;
    057    public static final Class<AbstractMethodError> ABSTRACT_METHOD_ERROR = AbstractMethodError.class;
    058    public static final Class<IllegalAccessError> ILLEGAL_ACCESS_ERROR = IllegalAccessError.class;
    059    public static final Class<InstantiationError> INSTANTIATION_ERROR = InstantiationError.class;
    060    public static final Class<NoSuchFieldError> NO_SUCH_FIELD_ERROR = NoSuchFieldError.class;
    061    public static final Class<NoSuchMethodError> NO_SUCH_METHOD_ERROR = NoSuchMethodError.class;
    062    public static final Class<NoClassDefFoundError> NO_CLASS_DEF_FOUND_ERROR = NoClassDefFoundError.class;
    063    public static final Class<UnsatisfiedLinkError> UNSATISFIED_LINK_ERROR = UnsatisfiedLinkError.class;
    064
    065    public static final Class<VerifyError> VERIFY_ERROR = VerifyError.class;
    066    /* UnsupportedClassVersionError is new in JDK 1.2 */
    067//    public static final Class UnsupportedClassVersionError = UnsupportedClassVersionError.class;
    068    /**
    069     * Run-Time Exceptions
    070     */
    071    public static final Class<NullPointerException> NULL_POINTER_EXCEPTION = NullPointerException.class;
    072    public static final Class<ArrayIndexOutOfBoundsException> ARRAY_INDEX_OUT_OF_BOUNDS_EXCEPTION = ArrayIndexOutOfBoundsException.class;
    073    public static final Class<ArithmeticException> ARITHMETIC_EXCEPTION = ArithmeticException.class;
    074    public static final Class<NegativeArraySizeException> NEGATIVE_ARRAY_SIZE_EXCEPTION = NegativeArraySizeException.class;
    075    public static final Class<ClassCastException> CLASS_CAST_EXCEPTION = ClassCastException.class;
    076
    077    public static final Class<IllegalMonitorStateException> ILLEGAL_MONITOR_STATE = IllegalMonitorStateException.class;
    078    /**
    079     * Pre-defined exception arrays according to chapters 5.1-5.4 of the Java Virtual Machine Specification
    080     */
    081    private static final Class<?>[] EXCS_CLASS_AND_INTERFACE_RESOLUTION = {NO_CLASS_DEF_FOUND_ERROR, CLASS_FORMAT_ERROR, VERIFY_ERROR, ABSTRACT_METHOD_ERROR,
    082        EXCEPTION_IN_INITIALIZER_ERROR, ILLEGAL_ACCESS_ERROR}; // Chapter 5.1
    083
    084    private static final Class<?>[] EXCS_FIELD_AND_METHOD_RESOLUTION = {NO_SUCH_FIELD_ERROR, ILLEGAL_ACCESS_ERROR, NO_SUCH_METHOD_ERROR}; // Chapter 5.2
    085
    086    /**
    087     * Empty array.
    088     */
    089    private static final Class<?>[] EXCS_INTERFACE_METHOD_RESOLUTION = new Class[0]; // Chapter 5.3 (as below)
    090
    091    /**
    092     * Empty array.
    093     */
    094    private static final Class<?>[] EXCS_STRING_RESOLUTION = new Class[0];
    095
    096    // Chapter 5.4 (no errors but the ones that _always_ could happen! How stupid.)
    097    private static final Class<?>[] EXCS_ARRAY_EXCEPTION = {NULL_POINTER_EXCEPTION, ARRAY_INDEX_OUT_OF_BOUNDS_EXCEPTION};
    098
    099    /**
    100     * Creates a copy of the specified Exception Class array combined with any additional Exception classes.
    101     *
    102     * @param type the basic array type
    103     * @param extraClasses additional classes, if any
    104     * @return the merged array
    105     */
    106    public static Class<?>[] createExceptions(final EXCS type, final Class<?>... extraClasses) {
    107        switch (type) {
    108        case EXCS_CLASS_AND_INTERFACE_RESOLUTION:
    109            return mergeExceptions(EXCS_CLASS_AND_INTERFACE_RESOLUTION, extraClasses);
    110        case EXCS_ARRAY_EXCEPTION:
    111            return mergeExceptions(EXCS_ARRAY_EXCEPTION, extraClasses);
    112        case EXCS_FIELD_AND_METHOD_RESOLUTION:
    113            return mergeExceptions(EXCS_FIELD_AND_METHOD_RESOLUTION, extraClasses);
    114        case EXCS_INTERFACE_METHOD_RESOLUTION:
    115            return mergeExceptions(EXCS_INTERFACE_METHOD_RESOLUTION, extraClasses);
    116        case EXCS_STRING_RESOLUTION:
    117            return mergeExceptions(EXCS_STRING_RESOLUTION, extraClasses);
    118        default:
    119            throw new AssertionError("Cannot happen; unexpected enum value: " + type);
    120        }
    121    }
    122
    123    // helper method to merge exception class arrays
    124    private static Class<?>[] mergeExceptions(final Class<?>[] input, final Class<?>... extraClasses) {
    125        return ArrayUtils.addAll(input, extraClasses);
    126    }
    127
    128}