1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20
21 package org.apache.directory.server.ntp.messages;
22
23
24 import java.util.Arrays;
25 import java.util.Collections;
26 import java.util.List;
27
28
29 /**
30 * Stratum: This is a eight-bit unsigned integer indicating the stratum
31 * level of the local clock, with values defined as follows:
32 *
33 * Stratum Meaning
34 * ----------------------------------------------
35 * 0 unspecified or unavailable
36 * 1 primary reference (e.g., radio clock)
37 * 2-15 secondary reference (via NTP or SNTP)
38 * 16-255 reserved
39 *
40 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
41 * @version $Rev: 586763 $, $Date: 2007-10-20 19:26:29 +0200 (Sa, 20 Okt 2007) $
42 */
43 public final class StratumType implements Comparable<StratumType>
44 {
45 /**
46 * Constant for the "Unspecified or unavailable" stratum type.
47 */
48 public static final StratumType UNSPECIFIED = new StratumType( 0, "Unspecified or unavailable." );
49
50 /**
51 * Constant for the "Primary reference" stratum type.
52 */
53 public static final StratumType PRIMARY_REFERENCE = new StratumType( 1, "Primary reference." );
54
55 /**
56 * Constant for the "Secondary reference" stratum type.
57 */
58 public static final StratumType SECONDARY_REFERENCE = new StratumType( 2, "Secondary reference." );
59
60 /**
61 * Array for building a List of VALUES.
62 */
63 private static final StratumType[] values =
64 { UNSPECIFIED, PRIMARY_REFERENCE, SECONDARY_REFERENCE };
65
66 /**
67 * A list of all the stratum type constants.
68 */
69 public static final List<StratumType> VALUES = Collections.unmodifiableList( Arrays.asList( values ) );
70
71 /**
72 * The name of the stratum type.
73 */
74 private final String name;
75
76 /**
77 * The value/code for the stratum type.
78 */
79 private final int ordinal;
80
81
82 /**
83 * Private constructor prevents construction outside of this class.
84 */
85 private StratumType( int ordinal, String name )
86 {
87 this.ordinal = ordinal;
88 this.name = name;
89 }
90
91
92 /**
93 * Returns the stratum type when specified by its ordinal.
94 *
95 * @param type
96 * @return The stratum type.
97 */
98 public static StratumType getTypeByOrdinal( int type )
99 {
100 for ( int ii = 0; ii < values.length; ii++ )
101 {
102 if ( values[ii].ordinal == type )
103 {
104 return values[ii];
105 }
106 }
107
108 return UNSPECIFIED;
109 }
110
111
112 /**
113 * Returns the number associated with this stratum type.
114 *
115 * @return The stratum type ordinal.
116 */
117 public int getOrdinal()
118 {
119 return ordinal;
120 }
121
122
123 public int compareTo( StratumType that )
124 {
125 return ordinal - that.ordinal;
126 }
127
128
129 public String toString()
130 {
131 return name;
132 }
133 }