View Javadoc
1   /*
2    * reserved comment block
3    * DO NOT REMOVE OR ALTER!
4    */
5   package com.sun.org.apache.bcel.internal.generic;
6   
7   /* ====================================================================
8    * The Apache Software License, Version 1.1
9    *
10   * Copyright (c) 2001 The Apache Software Foundation.  All rights
11   * reserved.
12   *
13   * Redistribution and use in source and binary forms, with or without
14   * modification, are permitted provided that the following conditions
15   * are met:
16   *
17   * 1. Redistributions of source code must retain the above copyright
18   *    notice, this list of conditions and the following disclaimer.
19   *
20   * 2. Redistributions in binary form must reproduce the above copyright
21   *    notice, this list of conditions and the following disclaimer in
22   *    the documentation and/or other materials provided with the
23   *    distribution.
24   *
25   * 3. The end-user documentation included with the redistribution,
26   *    if any, must include the following acknowledgment:
27   *       "This product includes software developed by the
28   *        Apache Software Foundation (http://www.apache.org/)."
29   *    Alternately, this acknowledgment may appear in the software itself,
30   *    if and wherever such third-party acknowledgments normally appear.
31   *
32   * 4. The names "Apache" and "Apache Software Foundation" and
33   *    "Apache BCEL" must not be used to endorse or promote products
34   *    derived from this software without prior written permission. For
35   *    written permission, please contact apache@apache.org.
36   *
37   * 5. Products derived from this software may not be called "Apache",
38   *    "Apache BCEL", nor may "Apache" appear in their name, without
39   *    prior written permission of the Apache Software Foundation.
40   *
41   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
44   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
45   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
46   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
48   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
49   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
51   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52   * SUCH DAMAGE.
53   * ====================================================================
54   *
55   * This software consists of voluntary contributions made by many
56   * individuals on behalf of the Apache Software Foundation.  For more
57   * information on the Apache Software Foundation, please see
58   * <http://www.apache.org/>.
59   */
60  import com.sun.org.apache.bcel.internal.Constants;
61  import com.sun.org.apache.bcel.internal.Repository;
62  import com.sun.org.apache.bcel.internal.classfile.JavaClass;
63  
64  /**
65   * Denotes reference such as java.lang.String.
66   *
67   * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
68   */
69  public final class ObjectType extends ReferenceType {
70    private String class_name; // Class name of type
71  
72    /**
73     * @param class_name fully qualified class name, e.g. java.lang.String
74     */
75    public ObjectType(String class_name) {
76      super(Constants.T_REFERENCE, "L" + class_name.replace('.', '/') + ";");
77      this.class_name = class_name.replace('/', '.');
78    }
79  
80    /** @return name of referenced class
81     */
82    public String getClassName() { return class_name; }
83  
84    /** @return a hash code value for the object.
85     */
86    public int hashCode()  { return class_name.hashCode(); }
87  
88    /** @return true if both type objects refer to the same class.
89     */
90    public boolean equals(Object type) {
91      return (type instanceof ObjectType)?
92        ((ObjectType)type).class_name.equals(class_name) : false;
93    }
94  
95    /**
96     * If "this" doesn't reference a class, it references an interface
97     * or a non-existant entity.
98     */
99    public boolean referencesClass(){
100     JavaClass jc = Repository.lookupClass(class_name);
101     if (jc == null)
102       return false;
103     else
104       return jc.isClass();
105   }
106 
107   /**
108    * If "this" doesn't reference an interface, it references a class
109    * or a non-existant entity.
110    */
111   public boolean referencesInterface(){
112     JavaClass jc = Repository.lookupClass(class_name);
113     if (jc == null)
114       return false;
115     else
116       return !jc.isClass();
117   }
118 
119   public boolean subclassOf(ObjectType superclass){
120     if (this.referencesInterface() || superclass.referencesInterface())
121       return false;
122 
123     return Repository.instanceOf(this.class_name, superclass.class_name);
124   }
125 
126   /**
127    * Java Virtual Machine Specification edition 2, 5.4.4 Access Control
128    */
129   public boolean accessibleTo(ObjectType accessor) {
130     JavaClass jc = Repository.lookupClass(class_name);
131 
132     if(jc.isPublic()) {
133       return true;
134     } else {
135       JavaClass acc = Repository.lookupClass(accessor.class_name);
136       return acc.getPackageName().equals(jc.getPackageName());
137     }
138   }
139 }