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 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package sun.jvmstat.monitor;

/**

 * Provides a typesafe enumeration for describing units of measurement

 * attribute for instrumentation objects.

 *

 * @author   Brian Doherty

 */

public class Units implements java.io.Serializable {

    /* The enumeration values for this typesafe enumeration must be

     * kept in synchronization with the Units enum in the perfData.hpp file

     * in the HotSpot source base.

     */

    private static final int NUNITS=8;

    private static Units[] map = new Units[NUNITS];

    private final String name;

    private final int value;

    /**

     * An Invalid Units value.

     */

    public static final Units INVALID = new Units("Invalid", 0);

    /**

     * Units attribute representing unit-less quantities.

     */

    public static final Units NONE = new Units("None", 1);

    /**

     * Units attribute representing Bytes.

     */

    public static final Units BYTES = new Units("Bytes", 2);

    /**

     * Units attribute representing Ticks.

     */

    public static final Units TICKS = new Units("Ticks", 3);

    /**

     * Units attribute representing a count of events.

     */

    public static final Units EVENTS = new Units("Events", 4);

    /**

     * Units attribute representing String data. Although not really

     * a unit of measure, this Units value serves to distinguish String

     * instrumentation objects from instrumentation objects of other types.

     */

    public static final Units STRING = new Units("String", 5);

    /**

     * Units attribute representing Hertz (frequency).

     */

    public static final Units HERTZ = new Units("Hertz", 6);

    /**

     * Returns a string describing this Unit of measurement attribute

     *

     * @return String - a descriptive string for this enum.

     */

    public String toString() {

        return name;

    }

    /**

     * Returns the integer representation of this Units attribute

     *

     * @return int - an integer representation of this Units attribute.

     */

    public int intValue() {

        return value;

    }

    /**

     * Maps an integer value to its corresponding Units attribute.

     * If the integer value does not have a corresponding Units enum

     * value, then {@link Units#INVALID} is returned.

     *

     * @param value an integer representation of counter Units

     * @return Units - the Units object for the given <code>value</code>

     *                 or {@link Units#INVALID} if out of range.

     */

    public static Units toUnits(int value) {

        if (value < 0 || value >= map.length || map[value] == null) {

            return INVALID;

        }

        return map[value];

    }

    private Units(String name, int value) {

        this.name = name;

        this.value = value;

        map[value] = this;

    }

    private static final long serialVersionUID = 6992337162326171013L;

}