org.glassfish.jersey.server.monitoring.ExecutionStatistics Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jersey-all Show documentation
jersey-all is a rebundled verison of Jersey as one OSGi bundle.
There is a newer version: 2.22.2
/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2013 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * http://glassfish.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package org.glassfish.jersey.server.monitoring;

import java.util.Date;
import java.util.Map;

/**
 * Monitoring statistics of execution of one target. {@code ExecutionStatistics} contains
 * {@link TimeWindowStatistics} for various time window sizes.
 * 
 * Statistics retrieved from Jersey runtime might be mutable and thanks to it might provide inconsistent data
 * as not all statistics are updated in the same time. To retrieve the immutable and consistent
 * statistics data the method {@link #snapshot()} should be used.
 *
 * @author Miroslav Fuksa (miroslav.fuksa at oracle.com)
 * @see MonitoringStatistics See monitoring statistics for general details about statistics.
 */
public interface ExecutionStatistics {

    /**
     * Return time when target was executed last time. The time is measured before the target was executed.
     *
     * @return Time of last execution.
     */
    public Date getLastStartTime();

    /**
     * Returns time window statistics for available time window sizes. The returned map contains sizes
     * of a time window in milliseconds as keys and
     * {@link TimeWindowStatistics time window statistics} for the corresponding time window
     * as value.
     *
     * @return Map with size of a time window in milliseconds as keys and
     *         {@link TimeWindowStatistics time window statistics} for the corresponding time window
     *         as value.
     */
    public Map getTimeWindowStatistics();

    /**
     * Get the immutable consistent snapshot of the monitoring statistics. Working with snapshots might
     * have negative performance impact as snapshot must be created but ensures consistency of data over time.
     * However, the usage of snapshot is encouraged to avoid working with inconsistent data. Not all statistics
     * must be updated in the same time on mutable version of statistics.
     *
     * @return Snapshot of execution statistics.
     */
    public ExecutionStatistics snapshot();
}