/**
* Copyright 2003-2010 Terracotta, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.sf.ehcache;
import java.io.Serializable;
/**
* A pre JDK1.5 compatible enum class to indicate the status of a {@link CacheManager} or {@link Cache}.
* <p/>
* ehcache historically used int values for status. This is unsuitable for third party use thus this class.
* Methods are provided to convert from the int status values to enum values and vice versa.
*
* @author Greg Luck
* @version $Id: Status.java 2154 2010-04-06 02:45:52Z cdennis $
* @since 1.2
*/
public final class Status implements Serializable {
/**
* The cache is uninitialised. It cannot be used.
*/
public static final Status STATUS_UNINITIALISED = new Status(0, "STATUS_UNINITIALISED");
/**
* The cache is alive. It can be used.
*/
public static final Status STATUS_ALIVE = new Status(1, "STATUS_ALIVE");
/**
* The cache is shudown. It cannot be used.
*/
public static final Status STATUS_SHUTDOWN = new Status(2, "STATUS_SHUTDOWN");
private static final long serialVersionUID = 2732730630423367732L;
private static final Status[] STATUSES = {STATUS_UNINITIALISED, STATUS_ALIVE, STATUS_SHUTDOWN};
private final String name;
private final int intValue;
private Status(int intValue, String name) {
this.intValue = intValue;
this.name = name;
}
/**
* Returns a string representation of the object. In general, the
* <code>toString</code> method returns a string that
* "textually represents" this object. The result should
* be a concise but informative representation that is easy for a
* person to read.
* It is recommended that all subclasses override this method.
* <p/>
* The <code>toString</code> method for class <code>Object</code>
* returns a string consisting of the name of the class of which the
* object is an instance, the at-sign character `<code>@</code>', and
* the unsigned hexadecimal representation of the hash code of the
* object. In other words, this method returns a string equal to the
* value of:
* <blockquote>
* <pre>
* getClass().getName() + '@' + Integer.toHexString(hashCode())
* </pre></blockquote>
*
* @return a string representation of the object.
*/
public String toString() {
return name;
}
/**
* @param statusAsInt an int argument between 1 and 3.
* @return an enum Status
* @throws IllegalArgumentException if the argument is not between 1 and 3
*/
public static Status convertIntToStatus(int statusAsInt) throws IllegalArgumentException {
if ((statusAsInt < STATUS_UNINITIALISED.intValue) || (statusAsInt > STATUS_SHUTDOWN.intValue)) {
throw new IllegalArgumentException("int value of statuses must be between 1 and three");
}
return STATUSES[statusAsInt];
}
/**
* Returns the int value of status, for backward compatibility with ehcache versions below 1.2
* @return the int value of this status.
*/
public int intValue() {
return intValue;
}
/**
* Indicates whether some other object is "equal to" this one.
* <p/>
* The <code>equals</code> method implements an equivalence relation
* on non-null object references:
* <ul>
* <li>It is <i>reflexive</i>: for any non-null reference value
* <code>x</code>, <code>x.equals(x)</code> should return
* <code>true</code>.
* <li>It is <i>symmetric</i>: for any non-null reference values
* <code>x</code> and <code>y</code>, <code>x.equals(y)</code>
* should return <code>true</code> if and only if
* <code>y.equals(x)</code> returns <code>true</code>.
* <li>It is <i>transitive</i>: for any non-null reference values
* <code>x</code>, <code>y</code>, and <code>z</code>, if
* <code>x.equals(y)</code> returns <code>true</code> and
* <code>y.equals(z)</code> returns <code>true</code>, then
* <code>x.equals(z)</code> should return <code>true</code>.
* <li>It is <i>consistent</i>: for any non-null reference values
* <code>x</code> and <code>y</code>, multiple invocations of
* <tt>x.equals(y)</tt> consistently return <code>true</code>
* or consistently return <code>false</code>, provided no
* information used in <code>equals</code> comparisons on the
* objects is modified.
* <li>For any non-null reference value <code>x</code>,
* <code>x.equals(null)</code> should return <code>false</code>.
* </ul>
* <p/>
* The <tt>equals</tt> method for class <code>Object</code> implements
* the most discriminating possible equivalence relation on objects;
* that is, for any non-null reference values <code>x</code> and
* <code>y</code>, this method returns <code>true</code> if and only
* if <code>x</code> and <code>y</code> refer to the same object
* (<code>x == y</code> has the value <code>true</code>).
* <p/>
* Note that it is generally necessary to override the <tt>hashCode</tt>
* method whenever this method is overridden, so as to maintain the
* general contract for the <tt>hashCode</tt> method, which states
* that equal objects must have equal hash codes.
*
* @param object the reference object with which to compare.
* @return <code>true</code> if this object is the same as the obj
* argument; <code>false</code> otherwise.
* @see #hashCode()
* @see java.util.Hashtable
*/
public boolean equals(Object object) {
if (!(object instanceof Status)) {
return false;
}
return ((Status) object).intValue == intValue;
}
/**
* Equality checker when the comparison object is of the same type.
* @param status the status to check
* @return true is the statuses are the same
*/
public boolean equals(Status status) {
if (status == null) {
return false;
} else {
return (intValue == status.intValue);
}
}
/**
* Returns a hash code value for Status. It is the underlying int value of the status.
* @return a hash code value for this object.
* @see Object#hashCode()
* @see java.util.Hashtable
*/
public int hashCode() {
return intValue;
}
}
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