1 /* RefAddr.java -- Abstract superclass of addresses used in References
2    Copyright (C) 2000, 2001 Free Software Foundation, Inc.
3 
4 This file is part of GNU Classpath.
5 
6 GNU Classpath is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10 
11 GNU Classpath is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GNU Classpath; see the file COPYING.  If not, write to the
18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 02110-1301 USA.
20 
21 Linking this library statically or dynamically with other modules is
22 making a combined work based on this library.  Thus, the terms and
23 conditions of the GNU General Public License cover the whole
24 combination.
25 
26 As a special exception, the copyright holders of this library give you
27 permission to link this library with independent modules to produce an
28 executable, regardless of the license terms of these independent
29 modules, and to copy and distribute the resulting executable under
30 terms of your choice, provided that you also meet, for each linked
31 independent module, the terms and conditions of the license of that
32 module.  An independent module is a module which is not derived from
33 or based on this library.  If you modify this library, you may extend
34 this exception to your version of the library, but you are not
35 obligated to do so.  If you do not wish to do so, delete this
36 exception statement from your version. */
37 
38 package javax.naming;
39 
40 import java.io.Serializable;
41 
42 /**
43  * Abstract superclass of addresses used in References.
44  * A <code>Reference</code> object contains a <code>Vector</code> of
45  * <code>RefAddr</code>s which are used to reference/address the object.
46  * This abstract superclass keeps track of the type of address, which will be
47  * returned by <code>getType()</code>. And defines a abstract method
48  * <code>getContent()</code> which must be implemented in concrete subclasses
49  * such as <code>BinaryRefAddr</code> and <code>StringRefAddr</code>.
50  *
51  * @see Reference
52  * @see BinaryRefAddr
53  * @see StringRefAddr
54  * @since 1.3
55  * @author Anthony Green (green@redhat.com)
56  * @author Mark Wielaard (mark@klomp.org)
57  */
58 public abstract class RefAddr implements Serializable
59 {
60   /**
61    * The string resprenstation of the type of address.
62    * Set by the constructor and returned by the getType() method.
63    */
64   protected String addrType;
65 
66   /**
67    * Protected constructor for use by subclasses.
68    * Sets the addrType field of this object to the supplied String.
69    *
70    * @exception NullPointerException if the supplied String is null.
71    */
RefAddr(String addrType)72   protected RefAddr(String addrType)
73   {
74         if (addrType == null)
75           throw new NullPointerException("addrType cannot be null");
76 
77     this.addrType = addrType;
78   }
79 
80   /**
81    * Returns the non-null address type given to the constructor.
82    */
getType()83   public String getType()
84   {
85     return addrType;
86   }
87 
88   /**
89    * Returns the possibly null content of this RefAddr.
90    * The actual value is defined by the non-abstract subclass.
91    */
getContent()92   public abstract Object getContent();
93 
94   /**
95    * Checks if the object is a RefAddr with the same type and content.
96    *
97    * @return true if the given object is an instance of RefAddr, the addrType
98    *         is the same as this addrType and the content is equals to the
99    *         content of this object.
100    */
equals(Object o)101   public boolean equals(Object o)
102   {
103     if (o instanceof RefAddr)
104       {
105         RefAddr refAddr = (RefAddr) o;
106         if (this.getType().equals(refAddr.getType()))
107         {
108           Object c1 = this.getContent();
109           Object c2 = refAddr.getContent();
110           if (c1 == null)
111             return c2 == null;
112           else
113             return c1.equals(c2);
114         }
115       }
116     return false;
117   }
118 
119   /**
120    * Returns the hashCode which is the hasCode of the String returned by
121    * <code>getType()</code> plus the hashCode of the Object returned by
122    * <code>getContent</code> (when not null).
123    */
hashCode()124   public int hashCode()
125   {
126     int result = getType().hashCode();
127     Object o = getContent();
128     if (o != null)
129       result += o.hashCode();
130 
131     return result;
132   }
133 
134   /**
135    * Returns a String representation of the RefAddr.
136    * Should only be used for debugging purposes.
137    */
toString()138   public String toString()
139   {
140     return "[RefAddr type: " + getType() + " content: " + getContent() + ']';
141   }
142 }
143