001/* RefAddr.java -- Abstract superclass of addresses used in References 002 Copyright (C) 2000, 2001 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038package javax.naming; 039 040import java.io.Serializable; 041 042/** 043 * Abstract superclass of addresses used in References. 044 * A <code>Reference</code> object contains a <code>Vector</code> of 045 * <code>RefAddr</code>s which are used to reference/address the object. 046 * This abstract superclass keeps track of the type of address, which will be 047 * returned by <code>getType()</code>. And defines a abstract method 048 * <code>getContent()</code> which must be implemented in concrete subclasses 049 * such as <code>BinaryRefAddr</code> and <code>StringRefAddr</code>. 050 * 051 * @see Reference 052 * @see BinaryRefAddr 053 * @see StringRefAddr 054 * @since 1.3 055 * @author Anthony Green (green@redhat.com) 056 * @author Mark Wielaard (mark@klomp.org) 057 */ 058public abstract class RefAddr implements Serializable 059{ 060 /** 061 * The string resprenstation of the type of address. 062 * Set by the constructor and returned by the getType() method. 063 */ 064 protected String addrType; 065 066 /** 067 * Protected constructor for use by subclasses. 068 * Sets the addrType field of this object to the supplied String. 069 * 070 * @exception NullPointerException if the supplied String is null. 071 */ 072 protected RefAddr(String addrType) 073 { 074 if (addrType == null) 075 throw new NullPointerException("addrType cannot be null"); 076 077 this.addrType = addrType; 078 } 079 080 /** 081 * Returns the non-null address type given to the constructor. 082 */ 083 public String getType() 084 { 085 return addrType; 086 } 087 088 /** 089 * Returns the possibly null content of this RefAddr. 090 * The actual value is defined by the non-abstract subclass. 091 */ 092 public abstract Object getContent(); 093 094 /** 095 * Checks if the object is a RefAddr with the same type and content. 096 * 097 * @return true if the given object is an instance of RefAddr, the addrType 098 * is the same as this addrType and the content is equals to the 099 * content of this object. 100 */ 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 */ 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 */ 138 public String toString() 139 { 140 return "[RefAddr type: " + getType() + " content: " + getContent() + ']'; 141 } 142}