    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;
    019
    020/**
    021 * Exception constants.
    022 * @since 6.0 (intended to replace the InstructionConstant interface)
    023 */
    024public final class ExceptionConst {
    025
    026    /**
    027     * The mother of all exceptions
    028     */
    029    public static final Class<Throwable> THROWABLE = Throwable.class;
    030
    031    /**
    032     * Super class of any run-time exception
    033     */
    034    public static final Class<RuntimeException> RUNTIME_EXCEPTION = RuntimeException.class;
    035
    036    /**
    037     * Super class of any linking exception (aka Linkage Error)
    038     */
    039    public static final Class<LinkageError> LINKING_EXCEPTION = LinkageError.class;
    040
    041    /**
    042     * Linking Exceptions
    043     */
    044    public static final Class<ClassCircularityError> CLASS_CIRCULARITY_ERROR = ClassCircularityError.class;
    045    public static final Class<ClassFormatError> CLASS_FORMAT_ERROR = ClassFormatError.class;
    046    public static final Class<ExceptionInInitializerError> EXCEPTION_IN_INITIALIZER_ERROR = ExceptionInInitializerError.class;
    047    public static final Class<IncompatibleClassChangeError> INCOMPATIBLE_CLASS_CHANGE_ERROR = IncompatibleClassChangeError.class;
    048    public static final Class<AbstractMethodError> ABSTRACT_METHOD_ERROR = AbstractMethodError.class;
    049    public static final Class<IllegalAccessError> ILLEGAL_ACCESS_ERROR = IllegalAccessError.class;
    050    public static final Class<InstantiationError> INSTANTIATION_ERROR = InstantiationError.class;
    051    public static final Class<NoSuchFieldError> NO_SUCH_FIELD_ERROR = NoSuchFieldError.class;
    052    public static final Class<NoSuchMethodError> NO_SUCH_METHOD_ERROR = NoSuchMethodError.class;
    053    public static final Class<NoClassDefFoundError> NO_CLASS_DEF_FOUND_ERROR = NoClassDefFoundError.class;
    054    public static final Class<UnsatisfiedLinkError> UNSATISFIED_LINK_ERROR = UnsatisfiedLinkError.class;
    055    public static final Class<VerifyError> VERIFY_ERROR = VerifyError.class;
    056    /* UnsupportedClassVersionError is new in JDK 1.2 */
    057//    public static final Class UnsupportedClassVersionError = UnsupportedClassVersionError.class;
    058
    059    /**
    060     * Run-Time Exceptions
    061     */
    062    public static final Class<NullPointerException> NULL_POINTER_EXCEPTION = NullPointerException.class;
    063    public static final Class<ArrayIndexOutOfBoundsException> ARRAY_INDEX_OUT_OF_BOUNDS_EXCEPTION
    064                                                            = ArrayIndexOutOfBoundsException.class;
    065    public static final Class<ArithmeticException> ARITHMETIC_EXCEPTION = ArithmeticException.class;
    066    public static final Class<NegativeArraySizeException> NEGATIVE_ARRAY_SIZE_EXCEPTION = NegativeArraySizeException.class;
    067    public static final Class<ClassCastException> CLASS_CAST_EXCEPTION = ClassCastException.class;
    068    public static final Class<IllegalMonitorStateException> ILLEGAL_MONITOR_STATE = IllegalMonitorStateException.class;
    069
    070    /**
    071     * Pre-defined exception arrays according to chapters 5.1-5.4 of the Java Virtual
    072     * Machine Specification
    073     */
    074    private static final Class<?>[] EXCS_CLASS_AND_INTERFACE_RESOLUTION = {
    075            NO_CLASS_DEF_FOUND_ERROR, CLASS_FORMAT_ERROR, VERIFY_ERROR, ABSTRACT_METHOD_ERROR,
    076            EXCEPTION_IN_INITIALIZER_ERROR, ILLEGAL_ACCESS_ERROR
    077    }; // Chapter 5.1
    078    private static final Class<?>[] EXCS_FIELD_AND_METHOD_RESOLUTION = {
    079            NO_SUCH_FIELD_ERROR, ILLEGAL_ACCESS_ERROR, NO_SUCH_METHOD_ERROR
    080    }; // Chapter 5.2
    081    private static final Class<?>[] EXCS_INTERFACE_METHOD_RESOLUTION = new Class[0]; // Chapter 5.3 (as below)
    082    private static final Class<?>[] EXCS_STRING_RESOLUTION = new Class[0];
    083    // Chapter 5.4 (no errors but the ones that _always_ could happen! How stupid.)
    084    private static final Class<?>[] EXCS_ARRAY_EXCEPTION = {
    085            NULL_POINTER_EXCEPTION, ARRAY_INDEX_OUT_OF_BOUNDS_EXCEPTION
    086    };
    087
    088    /**
    089     * Enum corresponding to the various Exception Class arrays,
    090     * used by {@link ExceptionConst#createExceptions(EXCS, Class...)}
    091     */
    092    public enum EXCS {
    093        EXCS_CLASS_AND_INTERFACE_RESOLUTION,
    094        EXCS_FIELD_AND_METHOD_RESOLUTION,
    095        EXCS_INTERFACE_METHOD_RESOLUTION,
    096        EXCS_STRING_RESOLUTION,
    097        EXCS_ARRAY_EXCEPTION,
    098    }
    099
    100    // helper method to merge exception class arrays
    101    private static Class<?>[] mergeExceptions(final Class<?>[] input, final Class<?> ... extraClasses) {
    102        final int extraLen = extraClasses == null ? 0 : extraClasses.length;
    103        final Class<?>[] excs = new Class<?>[input.length + extraLen];
    104        System.arraycopy(input, 0, excs, 0, input.length);
    105        if (extraLen > 0) {
    106            System.arraycopy(extraClasses, 0, excs, input.length, extraLen);
    107        }
    108        return excs;
    109    }
    110
    111    /**
    112     * Creates a copy of the specified Exception Class array combined with any additional Exception classes.
    113     * @param type the basic array type
    114     * @param extraClasses additional classes, if any
    115     * @return the merged array
    116     */
    117    public static Class<?>[] createExceptions(final EXCS type, final Class<?> ... extraClasses) {
    118        switch (type) {
    119        case EXCS_CLASS_AND_INTERFACE_RESOLUTION:
    120            return mergeExceptions(EXCS_CLASS_AND_INTERFACE_RESOLUTION, extraClasses);
    121        case EXCS_ARRAY_EXCEPTION:
    122            return mergeExceptions(EXCS_ARRAY_EXCEPTION, extraClasses);
    123        case EXCS_FIELD_AND_METHOD_RESOLUTION:
    124            return mergeExceptions(EXCS_FIELD_AND_METHOD_RESOLUTION, extraClasses);
    125        case EXCS_INTERFACE_METHOD_RESOLUTION:
    126            return mergeExceptions(EXCS_INTERFACE_METHOD_RESOLUTION, extraClasses);
    127        case EXCS_STRING_RESOLUTION:
    128            return mergeExceptions(EXCS_STRING_RESOLUTION, extraClasses);
    129        default:
    130            throw new AssertionError("Cannot happen; unexpected enum value: " + type);
    131        }
    132    }
    133
    134
    135}