/*
* Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
package javafx.animation;
import com.sun.javafx.tk.
Toolkit;
import com.sun.scenario.animation.
AbstractMasterTimer;
import com.sun.scenario.animation.shared.
TimerReceiver;
import java.security.
AccessControlContext;
import java.security.
AccessController;
import java.security.
PrivilegedAction;
/**
* The class {@code AnimationTimer} allows to create a timer, that is called in
* each frame while it is active.
*
* An extending class has to override the method {@link #handle(long)} which
* will be called in every frame.
*
* The methods {@link AnimationTimer#start()} and {@link #stop()} allow to start
* and stop the timer.
*
*
* @since JavaFX 2.0
*/
public abstract class
AnimationTimer {
private class
AnimationTimerReceiver implements
TimerReceiver {
@
Override public void
handle(final long
now) {
if (
accessCtrlCtx == null) {
throw new
IllegalStateException("Error: AccessControlContext not captured");
}
AccessController.
doPrivileged((
PrivilegedAction<
Void>) () -> {
AnimationTimer.this.
handle(
now);
return null;
},
accessCtrlCtx);
}
}
private final
AbstractMasterTimer timer;
private final
AnimationTimerReceiver timerReceiver = new
AnimationTimerReceiver();
private boolean
active;
// Access control context, captured in start()
private
AccessControlContext accessCtrlCtx = null;
/**
* Creates a new timer.
*/
public
AnimationTimer() {
timer =
Toolkit.
getToolkit().
getMasterTimer();
}
// For testing only
AnimationTimer(
AbstractMasterTimer timer) {
this.
timer =
timer;
}
/**
* This method needs to be overridden by extending classes. It is going to
* be called in every frame while the {@code AnimationTimer} is active.
*
* @param now
* The timestamp of the current frame given in nanoseconds. This
* value will be the same for all {@code AnimationTimers} called
* during one frame.
*/
public abstract void
handle(long
now);
/**
* Starts the {@code AnimationTimers}. Once it is started, the
* {@link #handle(long)} method of this {@code AnimationTimers} will be
* called in every frame.
*
* The {@code AnimationTimers} can be stopped by calling {@link #stop()}.
*/
public void
start() {
if (!
active) {
// Capture the Access Control Context to be used during the animation pulse
accessCtrlCtx =
AccessController.
getContext();
timer.
addAnimationTimer(
timerReceiver);
active = true;
}
}
/**
* Stops the {@code AnimationTimers}. It can be activated again by calling
* {@link #start()}.
*/
public void
stop() {
if (
active) {
timer.
removeAnimationTimer(
timerReceiver);
active = false;
}
}
}