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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * 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).
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package jdk.jfr.internal.management;

import java.time.Duration;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import jdk.jfr.EventType;
import jdk.jfr.internal.JVMSupport;
import jdk.jfr.internal.LogLevel;
import jdk.jfr.internal.LogTag;
import jdk.jfr.internal.Logger;
import jdk.jfr.internal.MetadataRepository;
import jdk.jfr.internal.Utils;
import jdk.jfr.internal.instrument.JDKEvents;

The management API in module jdk.management.jfr should be built on top of the
public API in jdk.jfr. Before putting more functionality here, consider if it
should not be part of the public API, and if not, please provide motivation
/**
 * The management API in module jdk.management.jfr should be built on top of the
 * public API in jdk.jfr. Before putting more functionality here, consider if it
 * should not be part of the public API, and if not, please provide motivation
 *
 */
public final class ManagementSupport {

    // Purpose of this method is to expose the event types to the
    // FlightRecorderMXBean without instantiating Flight Recorder.
    //
    // This allows:
    //
    // 1) discoverability, so event settings can be exposed without the need to
    // create a new Recording in FlightrecorderMXBean.
    //
    // 2) a graphical JMX client to list all attributes to the user, without
    // loading JFR memory buffers. This is especially important when there is
    // no intent to use Flight Recorder.
    //
    // An alternative design would be to make FlightRecorder#getEventTypes
    // static, but it would the make the API look strange
    //
    public static List<EventType> getEventTypes() {
        // would normally be checked when a Flight Recorder instance is created
        Utils.checkAccessFlightRecorder();
        if (JVMSupport.isNotAvailable()) {
            return new ArrayList<>();
        }
        JDKEvents.initialize(); // make sure JDK events are available
        return Collections.unmodifiableList(MetadataRepository.getInstance().getRegisteredEventTypes());
    }

    // Reuse internal code for parsing a timespan
    public static long parseTimespan(String s) {
        return Utils.parseTimespan(s);
    }

    // Reuse internal code for formatting settings
    public static final String formatTimespan(Duration dValue, String separation) {
        return Utils.formatTimespan(dValue, separation);
    }

    // Reuse internal logging mechanism
    public static void logError(String message) {
        Logger.log(LogTag.JFR, LogLevel.ERROR, message);
    }
}