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Java > Open Source Codes > com > sun > org > apache > bcel > internal > generic > ObjectType


1 package com.sun.org.apache.bcel.internal.generic;
2
3 /* ====================================================================
4  * The Apache Software License, Version 1.1
5  *
6  * Copyright (c) 2001 The Apache Software Foundation. All rights
7  * reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  * notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  * notice, this list of conditions and the following disclaimer in
18  * the documentation and/or other materials provided with the
19  * distribution.
20  *
21  * 3. The end-user documentation included with the redistribution,
22  * if any, must include the following acknowledgment:
23  * "This product includes software developed by the
24  * Apache Software Foundation (http://www.apache.org/)."
25  * Alternately, this acknowledgment may appear in the software itself,
26  * if and wherever such third-party acknowledgments normally appear.
27  *
28  * 4. The names "Apache" and "Apache Software Foundation" and
29  * "Apache BCEL" must not be used to endorse or promote products
30  * derived from this software without prior written permission. For
31  * written permission, please contact apache@apache.org.
32  *
33  * 5. Products derived from this software may not be called "Apache",
34  * "Apache BCEL", nor may "Apache" appear in their name, without
35  * prior written permission of the Apache Software Foundation.
36  *
37  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
40  * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
44  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
45  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
46  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
47  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48  * SUCH DAMAGE.
49  * ====================================================================
50  *
51  * This software consists of voluntary contributions made by many
52  * individuals on behalf of the Apache Software Foundation. For more
53  * information on the Apache Software Foundation, please see
54  * <http://www.apache.org/>.
55  */
56 import com.sun.org.apache.bcel.internal.Constants;
57 import com.sun.org.apache.bcel.internal.Repository;
58 import com.sun.org.apache.bcel.internal.classfile.JavaClass;
59
60 /**
61  * Denotes reference such as java.lang.String.
62  *
63  * @version $Id: ObjectType.java,v 1.1.1.1 2001/10/29 20:00:25 jvanzyl Exp $
64  * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
65  */
66 public final class ObjectType extends ReferenceType {
67   private String JavaDoc class_name; // Class name of type
68
69   /**
70    * @param class_name fully qualified class name, e.g. java.lang.String
71    */
72   public ObjectType(String JavaDoc class_name) {
73     super(Constants.T_REFERENCE, "L" + class_name.replace('.', '/') + ";");
74     this.class_name = class_name.replace('/', '.');
75   }
76
77   /** @return name of referenced class
78    */
79   public String JavaDoc getClassName() { return class_name; }
80
81   /** @return a hash code value for the object.
82    */
83   public int hashCode() { return class_name.hashCode(); }
84
85   /** @return true if both type objects refer to the same class.
86    */
87   public boolean equals(Object JavaDoc type) {
88     return (type instanceof ObjectType)?
89       ((ObjectType)type).class_name.equals(class_name) : false;
90   }
91
92   /**
93    * If "this" doesn't reference a class, it references an interface
94    * or a non-existant entity.
95    */
96   public boolean referencesClass(){
97     JavaClass jc = Repository.lookupClass(class_name);
98     if (jc == null)
99       return false;
100     else
101       return jc.isClass();
102   }
103   
104   /**
105    * If "this" doesn't reference an interface, it references a class
106    * or a non-existant entity.
107    */
108   public boolean referencesInterface(){
109     JavaClass jc = Repository.lookupClass(class_name);
110     if (jc == null)
111       return false;
112     else
113       return !jc.isClass();
114   }
115
116   public boolean subclassOf(ObjectType superclass){
117     if (this.referencesInterface() || superclass.referencesInterface())
118       return false;
119
120     return Repository.instanceOf(this.class_name, superclass.class_name);
121   }
122
123   /**
124    * Java Virtual Machine Specification edition 2, &#247; 5.4.4 Access Control
125    */
126   public boolean accessibleTo(ObjectType accessor) {
127     JavaClass jc = Repository.lookupClass(class_name);
128
129     if(jc.isPublic()) {
130       return true;
131     } else {
132       JavaClass acc = Repository.lookupClass(accessor.class_name);
133       return acc.getPackageName().equals(jc.getPackageName());
134     }
135   }
136 }
137
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