1 /*
   2  * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package javax.management;
  27 
  28 
  29 // java import
  30 import java.io.Serializable;
  31 
  32 
  33 /**
  34  * Represents an MBean attribute by associating its name with its value.
  35  * The MBean server and other objects use this class to get and set attributes values.
  36  *
  37  * @since 1.5
  38  */
  39 public class Attribute implements Serializable   {
  40 
  41     /* Serial version */
  42     private static final long serialVersionUID = 2484220110589082382L;
  43 
  44     /**
  45      * @serial Attribute name.
  46      */
  47     private String name;
  48 
  49     /**
  50      * @serial Attribute value
  51      */
  52     @SuppressWarnings("serial") // Conditionally serializable
  53     private Object value= null;
  54 
  55 
  56     /**
  57      * Constructs an Attribute object which associates the given attribute name with the given value.
  58      *
  59      * @param name A String containing the name of the attribute to be created. Cannot be null.
  60      * @param value The Object which is assigned to the attribute. This object must be of the same type as the attribute.
  61      *
  62      */
  63     public Attribute(String name, Object value) {
  64 
  65         if (name == null) {
  66             throw new RuntimeOperationsException(new IllegalArgumentException("Attribute name cannot be null "));
  67         }
  68 
  69         this.name = name;
  70         this.value = value;
  71     }
  72 
  73 
  74     /**
  75      * Returns a String containing the  name of the attribute.
  76      *
  77      * @return the name of the attribute.
  78      */
  79     public String getName()  {
  80         return name;
  81     }
  82 
  83     /**
  84      * Returns an Object that is the value of this attribute.
  85      *
  86      * @return the value of the attribute.
  87      */
  88     public Object getValue()  {
  89         return value;
  90     }
  91 
  92     /**
  93      * Compares the current Attribute Object with another Attribute Object.
  94      *
  95      * @param object  The Attribute that the current Attribute is to be compared with.
  96      *
  97      * @return  True if the two Attribute objects are equal, otherwise false.
  98      */
  99 
 100 
 101     public boolean equals(Object object)  {
 102         if (!(object instanceof Attribute)) {
 103             return false;
 104         }
 105         Attribute val = (Attribute) object;
 106 
 107         if (value == null) {
 108             if (val.getValue() == null) {
 109                 return name.equals(val.getName());
 110             } else {
 111                 return false;
 112             }
 113         }
 114 
 115         return ((name.equals(val.getName())) &&
 116                 (value.equals(val.getValue())));
 117     }
 118 
 119     /**
 120      * Returns a hash code value for this attribute.
 121      *
 122      * @return a hash code value for this attribute.
 123      */
 124     public int hashCode() {
 125         return name.hashCode() ^ (value == null ? 0 : value.hashCode());
 126     }
 127 
 128     /**
 129      * Returns a String object representing this Attribute's value. The format of this
 130      * string is not specified, but users can expect that two Attributes return the
 131      * same string if and only if they are equal.
 132      */
 133     public String toString() {
 134         return getName() + " = " + getValue();
 135     }
 136  }