volatilesequencer.java

来自「java pos,你可以直接编译运行,」· Java 代码 · 共 109 行

/*
 * Copyright (c) 2000 jPOS.org.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *    "This product includes software developed by the jPOS project 
 *    (http://www.jpos.org/)". Alternately, this acknowledgment may 
 *    appear in the software itself, if and wherever such third-party 
 *    acknowledgments normally appear.
 *
 * 4. The names "jPOS" and "jPOS.org" must not be used to endorse 
 *    or promote products derived from this software without prior 
 *    written permission. For written permission, please contact 
 *    [e-mail].
 *
 * 5. Products derived from this software may not be called "jPOS",
 *    nor may "jPOS" appear in their name, without prior written
 *    permission of the jPOS project.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  
 * IN NO EVENT SHALL THE JPOS PROJECT OR ITS CONTRIBUTORS BE LIABLE FOR 
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the jPOS Project.  For more
 * information please see <http://www.jpos.org/>.
 */

package org.jpos.core;

import java.util.HashMap;
import java.util.Map;

/**
 * @author [e-mail]
 * @version $Id: VolatileSequencer.java,v 1.6 2003/10/13 10:46:15 apr Exp $
 * @since jPOS 1.1
 *
 * A simple sequencer intended for Debugging applications.<br>
 * Production grade Sequencers are required to be persistent capables
 */
public class VolatileSequencer implements Sequencer, VolatileSequencerMBean {
    private Map map;
    public VolatileSequencer () {
        map = new HashMap();
    }
    /**
     * @param counterName
     * @param add increment
     * @return counterName's value + add
     */
    synchronized public int get (String counterName, int add) {
        int i = 0;
        Integer I = (Integer) map.get (counterName);
        if (I != null)
            i = I.intValue();
        i += add;
        map.put (counterName, new Integer (i));
        return i;
    }
    /**
     * @param counterName
     * @return counterName's value + 1
     */
    public int get (String counterName) {
        return get (counterName, 1);
    }
    /**
     * @param counterName
     * @param newValue
     * @return oldValue
     */
    synchronized public int set (String counterName, int newValue) {
        int oldValue = 0;
        Integer I = (Integer) map.get (counterName);
        if (I != null)
            oldValue = I.intValue();
        map.put (counterName, new Integer (newValue));
        return oldValue;
    }
    public String[] getCounterNames () {
        Object[] o = map.keySet().toArray();
        String[] s = new String [o.length];
        System.arraycopy (o, 0, s, 0, o.length);
        return s;
    }
}