001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.bcel;
020
021import org.apache.commons.lang3.ArrayUtils;
022
023/**
024 * Exception constants.
025 *
026 * @since 6.0 (intended to replace the InstructionConstant interface)
027 */
028public final class ExceptionConst {
029
030    /**
031     * Enum corresponding to the various Exception Class arrays, used by
032     * {@link ExceptionConst#createExceptions(EXCS, Class...)}.
033     */
034    public enum EXCS {
035
036        /** Exception class and interface resolution. */
037        EXCS_CLASS_AND_INTERFACE_RESOLUTION,
038
039        /** Exception field and method resolution. */
040        EXCS_FIELD_AND_METHOD_RESOLUTION,
041
042        /** Exception interface method resolution. */
043        EXCS_INTERFACE_METHOD_RESOLUTION,
044
045        /** Exception string resolution. */
046        EXCS_STRING_RESOLUTION,
047
048        /** Exception array exception. */
049        EXCS_ARRAY_EXCEPTION,
050    }
051
052    /** Private constructor - utility class. */
053    public ExceptionConst() {
054    }
055
056    /**
057     * The mother of all exceptions
058     */
059    public static final Class<Throwable> THROWABLE = Throwable.class;
060
061    /**
062     * Super class of any run-time exception
063     */
064    public static final Class<RuntimeException> RUNTIME_EXCEPTION = RuntimeException.class;
065
066    /**
067     * Super class of any linking exception (aka Linkage Error)
068     */
069    public static final Class<LinkageError> LINKING_EXCEPTION = LinkageError.class;
070
071    /**
072     * Linking Exceptions.
073     */
074
075    /** Exception class: ClassCircularityError. */
076    public static final Class<ClassCircularityError> CLASS_CIRCULARITY_ERROR = ClassCircularityError.class;
077
078    /** Exception class: ClassFormatError. */
079    public static final Class<ClassFormatError> CLASS_FORMAT_ERROR = ClassFormatError.class;
080
081    /** Exception class: ExceptionInInitializerError. */
082    public static final Class<ExceptionInInitializerError> EXCEPTION_IN_INITIALIZER_ERROR = ExceptionInInitializerError.class;
083
084    /** Exception class: IncompatibleClassChangeError. */
085    public static final Class<IncompatibleClassChangeError> INCOMPATIBLE_CLASS_CHANGE_ERROR = IncompatibleClassChangeError.class;
086
087    /** Exception class: AbstractMethodError. */
088    public static final Class<AbstractMethodError> ABSTRACT_METHOD_ERROR = AbstractMethodError.class;
089
090    /** Exception class: IllegalAccessError. */
091    public static final Class<IllegalAccessError> ILLEGAL_ACCESS_ERROR = IllegalAccessError.class;
092
093    /** Exception class: InstantiationError. */
094    public static final Class<InstantiationError> INSTANTIATION_ERROR = InstantiationError.class;
095
096    /** Exception class: NoSuchFieldError. */
097    public static final Class<NoSuchFieldError> NO_SUCH_FIELD_ERROR = NoSuchFieldError.class;
098
099    /** Exception class: NoSuchMethodError. */
100    public static final Class<NoSuchMethodError> NO_SUCH_METHOD_ERROR = NoSuchMethodError.class;
101
102    /** Exception class: NoClassDefFoundError. */
103    public static final Class<NoClassDefFoundError> NO_CLASS_DEF_FOUND_ERROR = NoClassDefFoundError.class;
104
105    /** Exception class: UnsatisfiedLinkError. */
106    public static final Class<UnsatisfiedLinkError> UNSATISFIED_LINK_ERROR = UnsatisfiedLinkError.class;
107
108    /** Exception class: VerifyError. */
109    public static final Class<VerifyError> VERIFY_ERROR = VerifyError.class;
110    /* UnsupportedClassVersionError is new in JDK 1.2 */
111//    public static final Class UnsupportedClassVersionError = UnsupportedClassVersionError.class;
112
113    /**
114     * Run-Time Exceptions.
115     */
116
117    /** Exception class: NullPointerException. */
118    public static final Class<NullPointerException> NULL_POINTER_EXCEPTION = NullPointerException.class;
119
120    /** Exception class: ArrayIndexOutOfBoundsException. */
121    public static final Class<ArrayIndexOutOfBoundsException> ARRAY_INDEX_OUT_OF_BOUNDS_EXCEPTION = ArrayIndexOutOfBoundsException.class;
122
123    /** Exception class: ArithmeticException. */
124    public static final Class<ArithmeticException> ARITHMETIC_EXCEPTION = ArithmeticException.class;
125
126    /** Exception class: NegativeArraySizeException. */
127    public static final Class<NegativeArraySizeException> NEGATIVE_ARRAY_SIZE_EXCEPTION = NegativeArraySizeException.class;
128
129    /** Exception class: ClassCastException. */
130    public static final Class<ClassCastException> CLASS_CAST_EXCEPTION = ClassCastException.class;
131
132    /** Exception class: IllegalMonitorStateException. */
133    public static final Class<IllegalMonitorStateException> ILLEGAL_MONITOR_STATE = IllegalMonitorStateException.class;
134
135    /**
136     * Pre-defined exception arrays according to chapters 5.1-5.4 of the Java Virtual Machine Specification
137     */
138    private static final Class<?>[] EXCS_CLASS_AND_INTERFACE_RESOLUTION = {NO_CLASS_DEF_FOUND_ERROR, CLASS_FORMAT_ERROR, VERIFY_ERROR, ABSTRACT_METHOD_ERROR,
139        EXCEPTION_IN_INITIALIZER_ERROR, ILLEGAL_ACCESS_ERROR}; // Chapter 5.1
140
141    private static final Class<?>[] EXCS_FIELD_AND_METHOD_RESOLUTION = {NO_SUCH_FIELD_ERROR, ILLEGAL_ACCESS_ERROR, NO_SUCH_METHOD_ERROR}; // Chapter 5.2
142
143    /**
144     * Empty array.
145     */
146    private static final Class<?>[] EXCS_INTERFACE_METHOD_RESOLUTION = new Class[0]; // Chapter 5.3 (as below)
147
148    /**
149     * Empty array.
150     */
151    private static final Class<?>[] EXCS_STRING_RESOLUTION = new Class[0];
152
153    // Chapter 5.4 (no errors but the ones that _always_ could happen! How stupid.)
154    private static final Class<?>[] EXCS_ARRAY_EXCEPTION = {NULL_POINTER_EXCEPTION, ARRAY_INDEX_OUT_OF_BOUNDS_EXCEPTION};
155
156    /**
157     * Creates a copy of the specified Exception Class array combined with any additional Exception classes.
158     *
159     * @param type the basic array type.
160     * @param extraClasses additional classes, if any.
161     * @return the merged array.
162     */
163    public static Class<?>[] createExceptions(final EXCS type, final Class<?>... extraClasses) {
164        switch (type) {
165        case EXCS_CLASS_AND_INTERFACE_RESOLUTION:
166            return mergeExceptions(EXCS_CLASS_AND_INTERFACE_RESOLUTION, extraClasses);
167        case EXCS_ARRAY_EXCEPTION:
168            return mergeExceptions(EXCS_ARRAY_EXCEPTION, extraClasses);
169        case EXCS_FIELD_AND_METHOD_RESOLUTION:
170            return mergeExceptions(EXCS_FIELD_AND_METHOD_RESOLUTION, extraClasses);
171        case EXCS_INTERFACE_METHOD_RESOLUTION:
172            return mergeExceptions(EXCS_INTERFACE_METHOD_RESOLUTION, extraClasses);
173        case EXCS_STRING_RESOLUTION:
174            return mergeExceptions(EXCS_STRING_RESOLUTION, extraClasses);
175        default:
176            throw new AssertionError("Cannot happen; unexpected enum value: " + type);
177        }
178    }
179
180    // helper method to merge exception class arrays
181    private static Class<?>[] mergeExceptions(final Class<?>[] input, final Class<?>... extraClasses) {
182        return ArrayUtils.addAll(input, extraClasses);
183    }
184
185}