1 /***
2 * Copyright 2003-2010 Terracotta, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package net.sf.ehcache;
18
19 import java.io.Serializable;
20
21 /***
22 * A pre JDK1.5 compatible enum class to indicate the status of a {@link CacheManager} or {@link Cache}.
23 * <p/>
24 * ehcache historically used int values for status. This is unsuitable for third party use thus this class.
25 * Methods are provided to convert from the int status values to enum values and vice versa.
26 *
27 * @author Greg Luck
28 * @version $Id: Status.html 13146 2011-08-01 17:12:39Z oletizi $
29 * @since 1.2
30 */
31 public final class Status implements Serializable {
32 /***
33 * The cache is uninitialised. It cannot be used.
34 */
35 public static final Status STATUS_UNINITIALISED = new Status(0, "STATUS_UNINITIALISED");
36 /***
37 * The cache is alive. It can be used.
38 */
39 public static final Status STATUS_ALIVE = new Status(1, "STATUS_ALIVE");
40 /***
41 * The cache is shudown. It cannot be used.
42 */
43 public static final Status STATUS_SHUTDOWN = new Status(2, "STATUS_SHUTDOWN");
44
45 private static final long serialVersionUID = 2732730630423367732L;
46
47 private static final Status[] STATUSES = {STATUS_UNINITIALISED, STATUS_ALIVE, STATUS_SHUTDOWN};
48
49 private final String name;
50 private final int intValue;
51
52 private Status(int intValue, String name) {
53 this.intValue = intValue;
54 this.name = name;
55
56 }
57
58 /***
59 * Returns a string representation of the object. In general, the
60 * <code>toString</code> method returns a string that
61 * "textually represents" this object. The result should
62 * be a concise but informative representation that is easy for a
63 * person to read.
64 * It is recommended that all subclasses override this method.
65 * <p/>
66 * The <code>toString</code> method for class <code>Object</code>
67 * returns a string consisting of the name of the class of which the
68 * object is an instance, the at-sign character `<code>@</code>', and
69 * the unsigned hexadecimal representation of the hash code of the
70 * object. In other words, this method returns a string equal to the
71 * value of:
72 * <blockquote>
73 * <pre>
74 * getClass().getName() + '@' + Integer.toHexString(hashCode())
75 * </pre></blockquote>
76 *
77 * @return a string representation of the object.
78 */
79 public String toString() {
80 return name;
81 }
82
83 /***
84 * @param statusAsInt an int argument between 1 and 3.
85 * @return an enum Status
86 * @throws IllegalArgumentException if the argument is not between 1 and 3
87 */
88 public static Status convertIntToStatus(int statusAsInt) throws IllegalArgumentException {
89 if ((statusAsInt < STATUS_UNINITIALISED.intValue) || (statusAsInt > STATUS_SHUTDOWN.intValue)) {
90 throw new IllegalArgumentException("int value of statuses must be between 1 and three");
91 }
92 return STATUSES[statusAsInt];
93 }
94
95 /***
96 * Returns the int value of status, for backward compatibility with ehcache versions below 1.2
97 * @return the int value of this status.
98 */
99 public int intValue() {
100 return intValue;
101 }
102
103 /***
104 * Indicates whether some other object is "equal to" this one.
105 * <p/>
106 * The <code>equals</code> method implements an equivalence relation
107 * on non-null object references:
108 * <ul>
109 * <li>It is <i>reflexive</i>: for any non-null reference value
110 * <code>x</code>, <code>x.equals(x)</code> should return
111 * <code>true</code>.
112 * <li>It is <i>symmetric</i>: for any non-null reference values
113 * <code>x</code> and <code>y</code>, <code>x.equals(y)</code>
114 * should return <code>true</code> if and only if
115 * <code>y.equals(x)</code> returns <code>true</code>.
116 * <li>It is <i>transitive</i>: for any non-null reference values
117 * <code>x</code>, <code>y</code>, and <code>z</code>, if
118 * <code>x.equals(y)</code> returns <code>true</code> and
119 * <code>y.equals(z)</code> returns <code>true</code>, then
120 * <code>x.equals(z)</code> should return <code>true</code>.
121 * <li>It is <i>consistent</i>: for any non-null reference values
122 * <code>x</code> and <code>y</code>, multiple invocations of
123 * <tt>x.equals(y)</tt> consistently return <code>true</code>
124 * or consistently return <code>false</code>, provided no
125 * information used in <code>equals</code> comparisons on the
126 * objects is modified.
127 * <li>For any non-null reference value <code>x</code>,
128 * <code>x.equals(null)</code> should return <code>false</code>.
129 * </ul>
130 * <p/>
131 * The <tt>equals</tt> method for class <code>Object</code> implements
132 * the most discriminating possible equivalence relation on objects;
133 * that is, for any non-null reference values <code>x</code> and
134 * <code>y</code>, this method returns <code>true</code> if and only
135 * if <code>x</code> and <code>y</code> refer to the same object
136 * (<code>x == y</code> has the value <code>true</code>).
137 * <p/>
138 * Note that it is generally necessary to override the <tt>hashCode</tt>
139 * method whenever this method is overridden, so as to maintain the
140 * general contract for the <tt>hashCode</tt> method, which states
141 * that equal objects must have equal hash codes.
142 *
143 * @param object the reference object with which to compare.
144 * @return <code>true</code> if this object is the same as the obj
145 * argument; <code>false</code> otherwise.
146 * @see #hashCode()
147 * @see java.util.Hashtable
148 */
149 public boolean equals(Object object) {
150 if (!(object instanceof Status)) {
151 return false;
152 }
153 return ((Status) object).intValue == intValue;
154 }
155
156 /***
157 * Equality checker when the comparison object is of the same type.
158 * @param status the status to check
159 * @return true is the statuses are the same
160 */
161 public boolean equals(Status status) {
162 if (status == null) {
163 return false;
164 } else {
165 return (intValue == status.intValue);
166 }
167 }
168
169 /***
170 * Returns a hash code value for Status. It is the underlying int value of the status.
171 * @return a hash code value for this object.
172 * @see Object#hashCode()
173 * @see java.util.Hashtable
174 */
175 public int hashCode() {
176 return intValue;
177 }
178
179 }