src/java.base/share/classes/jdk/internal/event/FileForceEvent.java - master - githubmirror/galahad

src/java.base/share/classes/jdk/internal/event/FileForceEvent.java
110 строк4 KB
Tim Prinzing
8329138: Convert JFR FileForceEvent to static mirror event
30 апр 2024, 18:39
30 апр 2024, 18:39f4caac8
/*
 * Copyright (c) 2024, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package jdk.internal.event;

/**
 * A JFR event for forced updates written to files.  This event is mirrored in
 * {@code jdk.jfr.events.FileForceEvent } where the event annotations are
 * provided.  Some of the methods are replaced by generated
 * methods when jfr is enabled.  Note that the order of the arguments of the
 * {@link #commit(long, long, String, boolean)} method
 * must be the same as the order of the fields.
 */
public class FileForceEvent extends Event {

    // THE ORDER OF THE FOLLOWING FIELDS IS IMPORTANT!
    // The order must match the argument order of the generated commit method.
    public String path;
    public boolean metaData;

    /**
     * Helper method to offer the data needed to potentially commit an event.
     * The duration of the operation is computed using the current
     * timestamp and the given start time.  If the duration is meets
     * or exceeds the configured value (determined by calling the generated method
     * {@link #shouldCommit(long)}), an event will be emitted by calling
     * {@link #commit(long, long, String, boolean)}.
     *
     * @param start     timestamp of the start of the operation
     * @param path      the full pathname of the file
     * @param metaData  true if the file metadata is updated
     */
    public static void offer(long start, String path, boolean metaData) {
        long duration = timestamp() - start;
        if (shouldCommit(duration)) {
            commit(start, duration, path, metaData);
        }
    }

    /**
     * Actually commit an event.  The implementation is generated automatically.
     * The order of the fields must be the same as the parameters in this method.
     *
     * @param start     timestamp of the start of the operation
     * @param duration  time in nanoseconds to complete the operation
     * @param path      the full pathname of the file
     * @param metaData  true if the file metadata is updated
     */
    public static void commit(long start, long duration, String path, boolean metaData) {
        // Generated by JFR
    }

    /**
     * Determine if an event should be emitted.  The duration of the operation
     * must exceed some threshold in order to commit the event.  The implementation
     * of this method is generated automatically if jfr is enabled.
     *
     * @param duration  time in nanoseconds to complete the operation
     * @return  true if the event should be commited
     */
    public static boolean shouldCommit(long duration) {
        // Generated by JFR
        return false;
    }

    /**
     * Determine if this kind of event is enabled.  The implementation
     * of this method is generated automatically if jfr is enabled.
     *
     * @return true if this type of event is enabled, false otherwise
     */
    public static boolean enabled() {
        // Generated by JFR
        return false;
    }

    /**
     * Fetch the current timestamp in nanoseconds.  This method is used
     * to determine the start and end of an operation.  The implementation
     * of this method is generated automatically if jfr is enabled.
     *
     * @return  the current timestamp value
     */
    public static long timestamp() {
        // Generated by JFR
        return 0L;
    }
}