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3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
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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).
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25  
26  package sun.jvmstat.monitor;
27  
28  /**
29   * Provides a typesafe enumeration for describing units of measurement
30   * attribute for instrumentation objects.
31   *
32   * @author   Brian Doherty
33   */
34  public class Units implements java.io.Serializable {
35  
36      /* The enumeration values for this typesafe enumeration must be
37       * kept in synchronization with the Units enum in the perfData.hpp file
38       * in the HotSpot source base.
39       */
40  
41      private static final int NUNITS=8;
42  
43      private static Units[] map = new Units[NUNITS];
44  
45      private final String name;
46      private final int value;
47  
48      /**
49       * An Invalid Units value.
50       */
51      public static final Units INVALID = new Units("Invalid", 0);
52  
53      /**
54       * Units attribute representing unit-less quantities.
55       */
56      public static final Units NONE = new Units("None", 1);
57  
58      /**
59       * Units attribute representing Bytes.
60       */
61      public static final Units BYTES = new Units("Bytes", 2);
62  
63      /**
64       * Units attribute representing Ticks.
65       */
66      public static final Units TICKS = new Units("Ticks", 3);
67  
68      /**
69       * Units attribute representing a count of events.
70       */
71      public static final Units EVENTS = new Units("Events", 4);
72  
73      /**
74       * Units attribute representing String data. Although not really
75       * a unit of measure, this Units value serves to distinguish String
76       * instrumentation objects from instrumentation objects of other types.
77       */
78      public static final Units STRING = new Units("String", 5);
79  
80      /**
81       * Units attribute representing Hertz (frequency).
82       */
83      public static final Units HERTZ = new Units("Hertz", 6);
84  
85      /**
86       * Returns a string describing this Unit of measurement attribute
87       *
88       * @return String - a descriptive string for this enum.
89       */
90      public String toString() {
91          return name;
92      }
93  
94      /**
95       * Returns the integer representation of this Units attribute
96       *
97       * @return int - an integer representation of this Units attribute.
98       */
99      public int intValue() {
100         return value;
101     }
102 
103     /**
104      * Maps an integer value to its corresponding Units attribute.
105      * If the integer value does not have a corresponding Units enum
106      * value, then {@link Units#INVALID} is returned.
107      *
108      * @param value an integer representation of counter Units
109      * @return Units - the Units object for the given <code>value</code>
110      *                 or {@link Units#INVALID} if out of range.
111      */
112     public static Units toUnits(int value) {
113 
114         if (value < 0 || value >= map.length || map[value] == null) {
115             return INVALID;
116         }
117 
118         return map[value];
119     }
120 
121     private Units(String name, int value) {
122         this.name = name;
123         this.value = value;
124         map[value] = this;
125     }
126 
127     private static final long serialVersionUID = 6992337162326171013L;
128 }