EventCounter.java

/**
 * Copyright 2010 Archfirst
 *
 * 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 org.archfirst.common.datetime;

/**
 * EventCounter
 *
 * @author Naresh Bhatia
 */
public class EventCounter {
    private int totalEvents = 0;
    private long firstEventNanos = 0;
    private long lastEventNanos = 0;
    
    // ----- Commands -----
    public synchronized void onEvent() {
        totalEvents++;
        if (totalEvents == 1) {
            firstEventNanos = System.nanoTime();
        }
        lastEventNanos = System.nanoTime();
    }

    // ----- Queries -----
    public synchronized EventStats getStats() {
        return new EventStats(totalEvents, firstEventNanos, lastEventNanos);
    }
}