354 lines
14 KiB
Java
354 lines
14 KiB
Java
/*
|
|
* Copyright (c) 2016, 2019, 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.jfr;
|
|
|
|
import static jdk.jfr.internal.LogLevel.DEBUG;
|
|
import static jdk.jfr.internal.LogLevel.INFO;
|
|
import static jdk.jfr.internal.LogTag.JFR;
|
|
|
|
import java.security.AccessControlContext;
|
|
import java.security.AccessController;
|
|
import java.util.ArrayList;
|
|
import java.util.Collections;
|
|
import java.util.List;
|
|
import java.util.Objects;
|
|
|
|
import jdk.jfr.internal.JVM;
|
|
import jdk.jfr.internal.JVMSupport;
|
|
import jdk.jfr.internal.LogLevel;
|
|
import jdk.jfr.internal.Logger;
|
|
import jdk.jfr.internal.MetadataRepository;
|
|
import jdk.jfr.internal.Options;
|
|
import jdk.jfr.internal.PlatformRecorder;
|
|
import jdk.jfr.internal.PlatformRecording;
|
|
import jdk.jfr.internal.Repository;
|
|
import jdk.jfr.internal.RequestEngine;
|
|
import jdk.jfr.internal.Utils;
|
|
|
|
/**
|
|
* Class for accessing, controlling, and managing Flight Recorder.
|
|
* <p>
|
|
* This class provides the methods necessary for creating, starting, stopping,
|
|
* and destroying recordings.
|
|
*
|
|
* @since 8
|
|
*/
|
|
public final class FlightRecorder {
|
|
private static volatile FlightRecorder platformRecorder;
|
|
private static volatile boolean initialized;
|
|
private final PlatformRecorder internal;
|
|
|
|
private FlightRecorder(PlatformRecorder internal) {
|
|
this.internal = internal;
|
|
}
|
|
|
|
/**
|
|
* Returns an immutable list of the available recordings.
|
|
* <p>
|
|
* A recording becomes available when it is created. It becomes unavailable when it
|
|
* is in the {@code CLOSED} state, typically after a call to
|
|
* {@link Recording#close()}.
|
|
*
|
|
* @return a list of recordings, not {@code null}
|
|
*/
|
|
public List<Recording> getRecordings() {
|
|
List<Recording> recs = new ArrayList<>();
|
|
for (PlatformRecording r : internal.getRecordings()) {
|
|
recs.add(r.getRecording());
|
|
}
|
|
return Collections.unmodifiableList(recs);
|
|
}
|
|
|
|
/**
|
|
* Creates a snapshot of all available recorded data.
|
|
* <p>
|
|
* A snapshot is a synthesized recording in a {@code STOPPPED} state. If no data is
|
|
* available, a recording with size {@code 0} is returned.
|
|
* <p>
|
|
* A snapshot provides stable access to data for later operations (for example,
|
|
* operations to change the interval or to reduce the data size).
|
|
* <p>
|
|
* The following example shows how to create a snapshot and write a subset of the data to a file.
|
|
*
|
|
* <pre>
|
|
* <code>
|
|
* try (Recording snapshot = FlightRecorder.getFlightRecorder().takeSnapshot()) {
|
|
* if (snapshot.getSize() > 0) {
|
|
* snapshot.setMaxSize(100_000_000);
|
|
* snapshot.setMaxAge(Duration.ofMinutes(5));
|
|
* snapshot.dump(Paths.get("snapshot.jfr"));
|
|
* }
|
|
* }
|
|
* </code>
|
|
* </pre>
|
|
*
|
|
* The caller must close the recording when access to the data is no longer
|
|
* needed.
|
|
*
|
|
* @return a snapshot of all available recording data, not {@code null}
|
|
*/
|
|
public Recording takeSnapshot() {
|
|
Recording snapshot = new Recording();
|
|
snapshot.setName("Snapshot");
|
|
internal.fillWithRecordedData(snapshot.getInternal(), null);
|
|
return snapshot;
|
|
}
|
|
|
|
/**
|
|
* Registers an event class.
|
|
* <p>
|
|
* If the event class is already registered, then the invocation of this method is
|
|
* ignored.
|
|
*
|
|
* @param eventClass the event class to register, not {@code null}
|
|
*
|
|
* @throws IllegalArgumentException if class is abstract or not a subclass
|
|
* of {@link Event}
|
|
* @throws SecurityException if a security manager exists and the caller
|
|
* does not have {@code FlightRecorderPermission("registerEvent")}
|
|
*/
|
|
public static void register(Class<? extends Event> eventClass) {
|
|
Objects.requireNonNull(eventClass);
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return;
|
|
}
|
|
Utils.ensureValidEventSubclass(eventClass);
|
|
MetadataRepository.getInstance().register(eventClass);
|
|
}
|
|
|
|
/**
|
|
* Unregisters an event class.
|
|
* <p>
|
|
* If the event class is not registered, then the invocation of this method is
|
|
* ignored.
|
|
*
|
|
* @param eventClass the event class to unregistered, not {@code null}
|
|
* @throws IllegalArgumentException if a class is abstract or not a subclass
|
|
* of {@link Event}
|
|
*
|
|
* @throws SecurityException if a security manager exists and the caller
|
|
* does not have {@code FlightRecorderPermission("registerEvent")}
|
|
*/
|
|
public static void unregister(Class<? extends Event> eventClass) {
|
|
Objects.requireNonNull(eventClass);
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return;
|
|
}
|
|
Utils.ensureValidEventSubclass(eventClass);
|
|
MetadataRepository.getInstance().unregister(eventClass);
|
|
}
|
|
|
|
/**
|
|
* Returns the Flight Recorder for the platform.
|
|
*
|
|
* @return a Flight Recorder instance, not {@code null}
|
|
*
|
|
* @throws IllegalStateException if Flight Recorder can't be created (for
|
|
* example, if the Java Virtual Machine (JVM) lacks Flight Recorder
|
|
* support, or if the file repository can't be created or accessed)
|
|
*
|
|
* @throws SecurityException if a security manager exists and the caller does
|
|
* not have {@code FlightRecorderPermission("accessFlightRecorder")}
|
|
*/
|
|
public static FlightRecorder getFlightRecorder() throws IllegalStateException, SecurityException {
|
|
synchronized (PlatformRecorder.class) {
|
|
Utils.checkAccessFlightRecorder();
|
|
JVMSupport.ensureWithIllegalStateException();
|
|
if (platformRecorder == null) {
|
|
try {
|
|
platformRecorder = new FlightRecorder(new PlatformRecorder());
|
|
} catch (IllegalStateException ise) {
|
|
throw ise;
|
|
} catch (Exception e) {
|
|
throw new IllegalStateException("Can't create Flight Recorder. " + e.getMessage(), e);
|
|
}
|
|
// Must be in synchronized block to prevent instance leaking out
|
|
// before initialization is done
|
|
initialized = true;
|
|
Logger.log(JFR, INFO, "Flight Recorder initialized");
|
|
Logger.log(JFR, DEBUG, "maxchunksize: " + Options.getMaxChunkSize()+ " bytes");
|
|
Logger.log(JFR, DEBUG, "memorysize: " + Options.getMemorySize()+ " bytes");
|
|
Logger.log(JFR, DEBUG, "globalbuffersize: " + Options.getGlobalBufferSize()+ " bytes");
|
|
Logger.log(JFR, DEBUG, "globalbuffercount: " + Options.getGlobalBufferCount());
|
|
Logger.log(JFR, DEBUG, "dumppath: " + Options.getDumpPath());
|
|
Logger.log(JFR, DEBUG, "samplethreads: " + Options.getSampleThreads());
|
|
Logger.log(JFR, DEBUG, "stackdepth: " + Options.getStackDepth());
|
|
Logger.log(JFR, DEBUG, "threadbuffersize: " + Options.getThreadBufferSize());
|
|
Logger.log(JFR, LogLevel.INFO, "Created repository " + Repository.getRepository().getRepositoryPath().toString());
|
|
PlatformRecorder.notifyRecorderInitialized(platformRecorder);
|
|
}
|
|
}
|
|
return platformRecorder;
|
|
}
|
|
|
|
/**
|
|
* Adds a hook for a periodic event.
|
|
* <p>
|
|
* The implementation of the hook should return as soon as possible, to
|
|
* avoid blocking other Flight Recorder operations. The hook should emit
|
|
* one or more events of the specified type. When a hook is added, the
|
|
* interval at which the call is invoked is configurable using the
|
|
* {@code "period"} setting.
|
|
*
|
|
* @param eventClass the class that the hook should run for, not {@code null}
|
|
* @param hook the hook, not {@code null}
|
|
* @throws IllegalArgumentException if a class is not a subclass of
|
|
* {@link Event}, is abstract, or the hook is already added
|
|
* @throws IllegalStateException if the event class has the
|
|
* {@code Registered(false)} annotation and is not registered manually
|
|
* @throws SecurityException if a security manager exists and the caller
|
|
* does not have {@code FlightRecorderPermission("registerEvent")}
|
|
*/
|
|
public static void addPeriodicEvent(Class<? extends Event> eventClass, Runnable hook) throws SecurityException {
|
|
Objects.requireNonNull(eventClass);
|
|
Objects.requireNonNull(hook);
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return;
|
|
}
|
|
|
|
Utils.ensureValidEventSubclass(eventClass);
|
|
Utils.checkRegisterPermission();
|
|
AccessControlContext acc = AccessController.getContext();
|
|
RequestEngine.addHook(acc, EventType.getEventType(eventClass).getPlatformEventType(), hook);
|
|
}
|
|
|
|
/**
|
|
* Removes a hook for a periodic event.
|
|
*
|
|
* @param hook the hook to remove, not {@code null}
|
|
* @return {@code true} if hook is removed, {@code false} otherwise
|
|
* @throws SecurityException if a security manager exists and the caller
|
|
* does not have {@code FlightRecorderPermission("registerEvent")}
|
|
*/
|
|
public static boolean removePeriodicEvent(Runnable hook) throws SecurityException {
|
|
Objects.requireNonNull(hook);
|
|
Utils.checkRegisterPermission();
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return false;
|
|
}
|
|
return RequestEngine.removeHook(hook);
|
|
}
|
|
|
|
/**
|
|
* Returns an immutable list that contains all currently registered events.
|
|
* <p>
|
|
* By default, events are registered when they are first used, typically
|
|
* when an event object is allocated. To ensure an event is visible early,
|
|
* registration can be triggered by invoking the
|
|
* {@link FlightRecorder#register(Class)} method.
|
|
*
|
|
* @return list of events, not {@code null}
|
|
*/
|
|
public List<EventType> getEventTypes() {
|
|
return Collections.unmodifiableList(MetadataRepository.getInstance().getRegisteredEventTypes());
|
|
}
|
|
|
|
/**
|
|
* Adds a recorder listener and captures the {@code AccessControlContext} to
|
|
* use when invoking the listener.
|
|
* <p>
|
|
* If Flight Recorder is already initialized when the listener is added, then the method
|
|
* {@link FlightRecorderListener#recorderInitialized(FlightRecorder)} method is
|
|
* invoked before returning from this method.
|
|
*
|
|
* @param changeListener the listener to add, not {@code null}
|
|
*
|
|
* @throws SecurityException if a security manager exists and the caller
|
|
* does not have
|
|
* {@code FlightRecorderPermission("accessFlightRecorder")}
|
|
*/
|
|
public static void addListener(FlightRecorderListener changeListener) {
|
|
Objects.requireNonNull(changeListener);
|
|
Utils.checkAccessFlightRecorder();
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return;
|
|
}
|
|
PlatformRecorder.addListener(changeListener);
|
|
}
|
|
|
|
/**
|
|
* Removes a recorder listener.
|
|
* <p>
|
|
* If the same listener is added multiple times, only one instance is
|
|
* removed.
|
|
*
|
|
* @param changeListener listener to remove, not {@code null}
|
|
*
|
|
* @throws SecurityException if a security manager exists and the caller
|
|
* does not have
|
|
* {@code FlightRecorderPermission("accessFlightRecorder")}
|
|
*
|
|
* @return {@code true}, if the listener could be removed, {@code false}
|
|
* otherwise
|
|
*/
|
|
public static boolean removeListener(FlightRecorderListener changeListener) {
|
|
Objects.requireNonNull(changeListener);
|
|
Utils.checkAccessFlightRecorder();
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return false;
|
|
}
|
|
|
|
return PlatformRecorder.removeListener(changeListener);
|
|
}
|
|
|
|
/**
|
|
* Returns {@code true} if the Java Virtual Machine (JVM) has Flight Recorder capabilities.
|
|
* <p>
|
|
* This method can quickly check whether Flight Recorder can be
|
|
* initialized, without actually doing the initialization work. The value may
|
|
* change during runtime and it is not safe to cache it.
|
|
*
|
|
* @return {@code true}, if Flight Recorder is available, {@code false}
|
|
* otherwise
|
|
*
|
|
* @see FlightRecorderListener for callback when Flight Recorder is
|
|
* initialized
|
|
*/
|
|
public static boolean isAvailable() {
|
|
if (JVMSupport.isNotAvailable()) {
|
|
return false;
|
|
}
|
|
return JVM.getJVM().isAvailable();
|
|
}
|
|
|
|
/**
|
|
* Returns {@code true} if Flight Recorder is initialized.
|
|
*
|
|
* @return {@code true}, if Flight Recorder is initialized,
|
|
* {@code false} otherwise
|
|
*
|
|
* @see FlightRecorderListener for callback when Flight Recorder is
|
|
* initialized
|
|
*/
|
|
public static boolean isInitialized() {
|
|
return initialized;
|
|
}
|
|
|
|
PlatformRecorder getInternal() {
|
|
return internal;
|
|
}
|
|
}
|