    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.generic;
    019
    020import org.apache.bcel.Const;
    021import org.apache.bcel.Repository;
    022import org.apache.bcel.classfile.JavaClass;
    023
    024/**
    025 * Denotes reference such as java.lang.String.
    026 *
    027 */
    028public class ObjectType extends ReferenceType {
    029
    030    private final String class_name; // Class name of type
    031
    032    /**
    033     * @since 6.0
    034     */
    035    public static ObjectType getInstance(final String class_name) {
    036        return new ObjectType(class_name);
    037    }
    038
    039    /**
    040     * @param class_name fully qualified class name, e.g. java.lang.String
    041     */
    042    public ObjectType(final String class_name) {
    043        super(Const.T_REFERENCE, "L" + class_name.replace('.', '/') + ";");
    044        this.class_name = class_name.replace('/', '.');
    045    }
    046
    047
    048    /** @return name of referenced class
    049     */
    050    public String getClassName() {
    051        return class_name;
    052    }
    053
    054
    055    /** @return a hash code value for the object.
    056     */
    057    @Override
    058    public int hashCode() {
    059        return class_name.hashCode();
    060    }
    061
    062
    063    /** @return true if both type objects refer to the same class.
    064     */
    065    @Override
    066    public boolean equals( final Object type ) {
    067        return (type instanceof ObjectType)
    068                ? ((ObjectType) type).class_name.equals(class_name)
    069                : false;
    070    }
    071
    072
    073    /**
    074     * If "this" doesn't reference a class, it references an interface
    075     * or a non-existant entity.
    076     * @deprecated (since 6.0) this method returns an inaccurate result
    077     *   if the class or interface referenced cannot
    078     *   be found: use referencesClassExact() instead
    079     */
    080    @Deprecated
    081    public boolean referencesClass() {
    082        try {
    083            final JavaClass jc = Repository.lookupClass(class_name);
    084            return jc.isClass();
    085        } catch (final ClassNotFoundException e) {
    086            return false;
    087        }
    088    }
    089
    090
    091    /**
    092     * If "this" doesn't reference an interface, it references a class
    093     * or a non-existant entity.
    094     * @deprecated (since 6.0) this method returns an inaccurate result
    095     *   if the class or interface referenced cannot
    096     *   be found: use referencesInterfaceExact() instead
    097     */
    098    @Deprecated
    099    public boolean referencesInterface() {
    100        try {
    101            final JavaClass jc = Repository.lookupClass(class_name);
    102            return !jc.isClass();
    103        } catch (final ClassNotFoundException e) {
    104            return false;
    105        }
    106    }
    107
    108
    109    /**
    110     * Return true if this type references a class,
    111     * false if it references an interface.
    112     * @return true if the type references a class, false if
    113     *   it references an interface
    114     * @throws ClassNotFoundException if the class or interface
    115     *   referenced by this type can't be found
    116     */
    117    public boolean referencesClassExact() throws ClassNotFoundException {
    118        final JavaClass jc = Repository.lookupClass(class_name);
    119        return jc.isClass();
    120    }
    121
    122
    123    /**
    124     * Return true if this type references an interface,
    125     * false if it references a class.
    126     * @return true if the type references an interface, false if
    127     *   it references a class
    128     * @throws ClassNotFoundException if the class or interface
    129     *   referenced by this type can't be found
    130     */
    131    public boolean referencesInterfaceExact() throws ClassNotFoundException {
    132        final JavaClass jc = Repository.lookupClass(class_name);
    133        return !jc.isClass();
    134    }
    135
    136
    137    /**
    138     * Return true if this type is a subclass of given ObjectType.
    139     * @throws ClassNotFoundException if any of this class's superclasses
    140     *  can't be found
    141     */
    142    public boolean subclassOf( final ObjectType superclass ) throws ClassNotFoundException {
    143        if (this.referencesInterfaceExact() || superclass.referencesInterfaceExact()) {
    144            return false;
    145        }
    146        return Repository.instanceOf(this.class_name, superclass.class_name);
    147    }
    148
    149
    150    /**
    151     * Java Virtual Machine Specification edition 2, � 5.4.4 Access Control
    152     * @throws ClassNotFoundException if the class referenced by this type
    153     *   can't be found
    154     */
    155    public boolean accessibleTo( final ObjectType accessor ) throws ClassNotFoundException {
    156        final JavaClass jc = Repository.lookupClass(class_name);
    157        if (jc.isPublic()) {
    158            return true;
    159        }
    160        final JavaClass acc = Repository.lookupClass(accessor.class_name);
    161        return acc.getPackageName().equals(jc.getPackageName());
    162    }
    163}