Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
NumericGenerator |
|
| 1.5;1.5 |
1 | /* | |
2 | * Licensed to the Apache Software Foundation (ASF) under one or more | |
3 | * contributor license agreements. See the NOTICE file distributed with | |
4 | * this work for additional information regarding copyright ownership. | |
5 | * The ASF licenses this file to You under the Apache License, Version 2.0 | |
6 | * (the "License"); you may not use this file except in compliance with | |
7 | * the License. You may obtain a copy of the License at | |
8 | * | |
9 | * http://www.apache.org/licenses/LICENSE-2.0 | |
10 | * | |
11 | * Unless required by applicable law or agreed to in writing, software | |
12 | * distributed under the License is distributed on an "AS IS" BASIS, | |
13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
14 | * See the License for the specific language governing permissions and | |
15 | * limitations under the License. | |
16 | */ | |
17 | ||
18 | package org.apache.commons.id.serial; | |
19 | ||
20 | import org.apache.commons.id.AbstractStringIdentifierGenerator; | |
21 | ||
22 | import java.io.Serializable; | |
23 | ||
24 | /** | |
25 | * <p><code>NumericIdentifierGenerator</code> is an Identifier Generator | |
26 | * that generates an incrementing number as a String object.</p> | |
27 | * | |
28 | * <p>If the <code>wrap</code> argument passed to the constructor is set to | |
29 | * <code>true</code>, the sequence will wrap, returning negative values when | |
30 | * {@link Long#MAX_VALUE} reached; otherwise an {@link IllegalStateException} | |
31 | * will be thrown.</p> | |
32 | * | |
33 | * @author Commons-Id team | |
34 | * @version $Id: NumericGenerator.java 480488 2006-11-29 08:57:26Z bayard $ | |
35 | */ | |
36 | public class NumericGenerator extends AbstractStringIdentifierGenerator implements Serializable { | |
37 | ||
38 | /** | |
39 | * <code>serialVersionUID</code> is the serializable UID for the binary version of the class. | |
40 | */ | |
41 | private static final long serialVersionUID = 20060121L; | |
42 | ||
43 | /** Should the counter wrap. */ | |
44 | private boolean wrapping; | |
45 | /** The counter. */ | |
46 | 31 | private long count = 0; |
47 | ||
48 | /** | |
49 | * <p>Constructor.</p> | |
50 | * | |
51 | * @param wrap should the factory wrap when it reaches the maximum | |
52 | * long value (or throw an exception) | |
53 | * @param initialValue the initial long value to start at | |
54 | */ | |
55 | public NumericGenerator(boolean wrap, long initialValue) { | |
56 | 31 | super(); |
57 | 31 | this.wrapping = wrap; |
58 | 31 | this.count = initialValue; |
59 | 31 | } |
60 | ||
61 | /** | |
62 | * Returns the maximum length (number or characters) for an identifier | |
63 | * from this sequence. | |
64 | * | |
65 | * <p>The maximum value is determined from the length of the string | |
66 | * representation of {@link Long#MAX_VALUE}.</p> | |
67 | * | |
68 | * @return the maximum identifier length | |
69 | */ | |
70 | public long maxLength() { | |
71 | 7 | return AbstractStringIdentifierGenerator.MAX_LONG_NUMERIC_VALUE_LENGTH; |
72 | } | |
73 | ||
74 | /** | |
75 | * <p>Returns the minimum length (number of characters) for an identifier | |
76 | * from this sequence.</p> | |
77 | * | |
78 | * @return the minimum identifier length: <code>1</code> | |
79 | */ | |
80 | public long minLength() { | |
81 | 7 | return 1; |
82 | } | |
83 | ||
84 | /** | |
85 | * Getter for property wrap. | |
86 | * | |
87 | * @return <code>true</code> if this generator is set up to wrap. | |
88 | * | |
89 | */ | |
90 | public boolean isWrap() { | |
91 | 7 | return wrapping; |
92 | } | |
93 | ||
94 | /** | |
95 | * Sets the wrap property. | |
96 | * | |
97 | * @param wrap value for the wrap property | |
98 | * | |
99 | */ | |
100 | public void setWrap(boolean wrap) { | |
101 | 2 | this.wrapping = wrap; |
102 | 2 | } |
103 | ||
104 | public String nextStringIdentifier() { | |
105 | 30 | long value = 0; |
106 | 30 | if (wrapping) { |
107 | 21 | synchronized (this) { |
108 | 21 | value = count++; |
109 | 21 | } |
110 | 21 | } else { |
111 | 9 | synchronized (this) { |
112 | 9 | if (count == Long.MAX_VALUE) { |
113 | 4 | throw new IllegalStateException |
114 | ("The maximum number of identifiers has been reached"); | |
115 | } | |
116 | 5 | value = count++; |
117 | 5 | } |
118 | } | |
119 | 26 | return Long.toString(value); |
120 | } | |
121 | } |