/*
*
*
* Copyright 1990-2009 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program 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.
*
* This program 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 at /legal/license.txt).
*
* 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 Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*/
package com.sun.midp.lcdui;
import javax.microedition.lcdui.Display;
import java.util.Timer;
import java.util.TimerTask;
/**
* Class that allows Display to access
* Device specific calls in the native code
* like flashBacklight.
*/
public class DisplayDeviceAccess {
/**
* The Timer to service TimerTasks.
*/
private static Timer timerService = new Timer();
/**
* A TimerTask for backlight.
*/
private TimerTask task = null;
/**
* A TimerTask for vibrate.
*/
private TimerTask vibrateTask = null;
/**
* The interval, in microseconds between backlight
* toggles (in microseconds)
*/
private static int BLINK_RATE = 250;
/**
* Number of repetitions left in flash duration
*/
private int flashCount = 0;
/**
* We always want this to be false at the end of
* a flashBacklight call.
*/
private boolean isLit = false;
/**
* Requests a flashing effect for the device's backlight.
*
* @param displayId The display ID associated with this Display
* @param duration the number of milliseconds the backlight should be
* flashed, or zero if the flashing should be stopped
*
* @return true if the backlight can be controlled
*/
public synchronized boolean flashBacklight(int displayId, int duration) {
// Test for negative of duration is in public class
if (duration == 0) {
cancelTimer();
if (isLit) {
isLit = !isLit;
return toggleBacklight0(displayId);
} else {
return isBacklightSupported0(displayId);
}
} else {
setTimer(displayId, duration);
isLit = !isLit;
return toggleBacklight0(displayId);
}
}
/**
* Set a new timer. Determine <code>flashCount</code> based on
* <code>duration</code> divided by <code>BLINK_RATE</code>
*
* @param displayId The display ID associated with this Display
* @param duration the number of milliseconds the timer should be run
*/
private void setTimer(int displayId, int duration) {
cancelTimer();
try {
task = new TimerClient(displayId);
/* flash every <tt>BLINK_RATE</tt> miliseconds */
flashCount = duration / BLINK_RATE;
timerService.schedule(task, BLINK_RATE, BLINK_RATE);
} catch (IllegalStateException e) {
cancelTimer();
}
}
/**
* Cancel any running Timer.
*/
private void cancelTimer() {
if (task != null) {
task.cancel();
task = null;
}
flashCount = 0;
}
/**
* Inner class TimerTask
*
* Used to toggle the backlight and turn it off when
* the duration of the timer is up
*/
class TimerClient extends TimerTask {
/**
* Creates TimerClient to show backlight for
* Display with passed displayId.
*
* @param displayId The display ID associated with the caller Display
*/
TimerClient(int displayId) {
this.displayId = displayId;
}
/**
* If there are flashes left to perform,
* simply toggle the backlight.
*/
public final void run() {
if (flashCount > 0) {
flashCount--;
isLit = !isLit;
toggleBacklight0(displayId);
} else {
if (isLit) {
isLit = !isLit;
toggleBacklight0(displayId);
}
this.cancel();
}
}
/** The display ID associated with the caller Display */
private int displayId;
}
/**
* Toggles backlight.
*
* @param displayId The display ID associated with the caller Display
* @return true if backlight control is supported, false otherwise
*/
private native boolean toggleBacklight0(int displayId);
/**
* Tests if backlight is supported.
*
* @param displayId The display ID associated with the caller Display
* @return true if backlight control is supported, false otherwise
*/
private native boolean isBacklightSupported0(int displayId);
/**
* Requests for the device's vibrating.
*
* @param displayId The display ID associated with this Display
* @param duration the number of milliseconds the vibration should be
* on, or zero if the flashing should be stopped
*
* @return true if the vibration can be controlled
*/
public synchronized boolean vibrate(int displayId, int duration) {
// Test for negative of duration is in public class
if (duration == 0) {
cancelVibrateTimer();
return vibrate0(displayId, false);
} else {
setVibrateTimer(displayId, duration);
return vibrate0(displayId, true);
}
}
/**
* Set a new vibration timer.
* The timerTask will be executed after <code>duration</code> milliseconds.
*
* @param displayId The display ID associated with this Display
* @param duration the number of milliseconds the timer should be run
*/
private void setVibrateTimer(int displayId, int duration) {
cancelVibrateTimer();
try {
vibrateTask = new VibrateTimerClient(displayId);
timerService.schedule(vibrateTask, duration);
} catch (IllegalStateException e) {
cancelVibrateTimer();
}
}
/**
* Cancel any running vibration Timer.
*/
private void cancelVibrateTimer() {
if (vibrateTask != null) {
vibrateTask.cancel();
vibrateTask = null;
}
}
/**
* Inner class TimerTask
*
* Used to stop the device's vibration when
* the duration of the timer is up
*/
class VibrateTimerClient extends TimerTask {
/**
* Creates VibrateTimerClient to stop vibration for
* Display with passed displayId.
*
* @param displayId The display ID associated with the caller Display
*/
VibrateTimerClient(int displayId) {
this.displayId = displayId;
}
/**
* simply stop the vibration.
*
*/
public final void run() {
vibrate0(displayId, false);
this.cancel();
}
/** The display ID associated with the caller Display */
private int displayId;
}
/**
* Show vibration. Turn it on or turn it off.
*
* @param displayId The display ID associated with the caller Display
* @param turnVibrateOn true to turn on the vibration,
* or false to turn off it.
* @return true if vibration control is supported, false otherwise
*/
private native boolean vibrate0(int displayId, boolean turnVibrateOn);
}