Java Code Examples for jdk.jfr.internal.JVMSupport#isNotAvailable()

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());
}
 

/**
 * 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);
}
 

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());
}
 

/**
 * Returns an immutable list of predefined configurations for this Java Virtual Machine (JVM).
 *
 * @return the list of predefined configurations, not {@code null}
 */
public static List<Configuration> getConfigurations() {
    if (JVMSupport.isNotAvailable()) {
        return new ArrayList<>();
    }
    return Collections.unmodifiableList(JFC.getConfigurations());
}
 

/**
 * Returns an immutable list of predefined configurations for this JVM.
 *
 * @return the list of predefined configurations, not {@code null}
 */
public static List<Configuration> getConfigurations() {
    if (JVMSupport.isNotAvailable()) {
        return new ArrayList<>();
    }
    return Collections.unmodifiableList(JFC.getConfigurations());
}
 

/**
 * 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);
}
 

/**
 * 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);
}
 

/**
 * 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);
}
 

/**
 * 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();
}
 

/**
 * 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);
}
 

/**
 * 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);
}
 

/**
 * 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);
}
 

/**
 * 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);
}
 

/**
 * 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 {@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();
}
 

/**
 * 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);
}
 

/**
 * 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, the 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);
}
 

/**
 * Adds a callback 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);
}
 

/**
 * 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);
}
 

/**
 * 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);
}