AlarmClock
AlarmClock with features
- Alarm to wakeup
- Scheduling Task
- Recurring Task
- Sync and Async execution of Task
Basic Example and Usage
Maven dependency
<dependency>
<groupId>com.github.priytam</groupId>
<artifactId>alarm</artifactId>
<version>1.0.0</version>
</dependency>
Gradle dependency
compile 'com.github.priytam:alarm:1.0.0'
AlarmClock
public class AlarmClockExample {
static {
LogManager.getRootLogger().setLevel(Level.INFO);
BasicConfigurator.configure();
}
public static void main(String[] args) throws InterruptedException {
// Get and instance of clock
AlarmClock clock = AlarmClock.getInstance("TestClock");
//register to print 'ring ring' after 2 sec
clock.register(2000, id -> System.out.println("ring ring"));
//register to print 'ring ring1' after 3 sec
clock.register(3000, id -> System.out.println("ring ring1"));
//start this
clock.start();
//register to print 'ring ring2' after 2 sec
clock.register(2000, id -> System.out.println("ring ring2"));
//register to print 'ring ring3' after 2 sec
clock.register(1000, id -> System.out.println("ring ring3"));
//show all alarms set
System.out.println(clock.getTaskList().showEntries());
Thread.sleep( 6000);
clock.shutdown();
}
}
Output
object = com.clock.AlarmClockHeartbeatTask@17550481, time remaining = 98
object = com.clock.example.AlarmClockExample$$Lambda$5/321142942@2c6a3f77, time remaining = 999
object = com.clock.example.AlarmClockExample$$Lambda$1/1032616650@2ed94a8b, time remaining = 1993
object = com.clock.example.AlarmClockExample$$Lambda$4/1935637221@180bc464, time remaining = 1999
object = com.clock.example.AlarmClockExample$$Lambda$2/649734728@5f2050f6, time remaining = 2995
ring ring3
ring ring
ring ring2
ring ring1
Useful Methods
- start/shutdown: start and stop clock
- register (long, registrants): register an task
- registerWeaK (long, registrants): register a weak task meaning in high load GC may clean this registry
- setNumberOfThreads (int): clock task(registrant) execution pool size, default 2
- setMaxPendingThreads (int): max pending task (registrant), default 4000
- setThrowOnLatencyViolations (boolean): will throw error if set true and there is latency in execution or else execute, default true
- setStatisticsLogger (IAlarmClockStatisticsLogger): to record stats
- getTaskList(): All Task entries registered
Scheduling
public class ScheduleExample {
static {
LogManager.getRootLogger().setLevel(Level.INFO);
BasicConfigurator.configure();
}
public static void main(String[] args) {
//create a schedule
Schedule helloWorldSchedule = new Schedule("HelloWorldSchedule");
//register a task to print 'Hello world'
helloWorldSchedule.register(() -> System.out.println("Hello world"));
//will print 'Hello world' every day 5:10
helloWorldSchedule.addEntry(new DailyScheduleEntry(5, 10));
//will print 'Hello world' every hour 1' o clock , 2' o clock, 3' clock
helloWorldSchedule.addEntry(new HourlyScheduleEntry(0, 0));
//will print 'Hello world' every monday at 5:10
helloWorldSchedule.addEntry(new WeeklyScheduleEntry(WeeklyScheduleEntry.MONDAY, 5, 10));
//print schedule Status
System.out.println(helloWorldSchedule.getStatus());
//register another task to print hello Priytam and will run with all entries added above
helloWorldSchedule.register(() -> System.out.println("Hello Priytam"));
//shutdown
helloWorldSchedule.shutDown();
}
}
output
HourlyEntry (0m:0s)
Next time will be at: Sun Jun 14 02:00:00 IST 2020
DailyEntry (5h:10m:0s)
Next time will be at: Sun Jun 14 05:10:00 IST 2020
WeeklyEntry (2d:5h:10m:0s)
Next time will be at: Mon Jun 15 05:10:00 IST 2020
Useful methods
- Schedule(String clockName, int poolSize) : with custom pool size, default size 10
- start/shutdown : start and stop schedule
- register (Runnable) : schedule a task for execution
- unregister (Runnable) : remove task from schedule
- addEntry (IScheduleEntry) : add an entry [HourlyEntry, DailyEntry, WeeklyEntry] to schedule for all registered tasks
- removeEntry (IScheduleEntry): remove an entry [HourlyEntry, DailyEntry, WeeklyEntry] from schedule for all registered tasks
- getScheduleEntries : List all entries in schedule
- getRegistrants : List all tasks registered in schedule
- getStatus(): String status of scheduled tasks
- unregisterAll() : unregister all task
- getNextExecutionTime() : next execution time
- getScheduleString() : schedule short info
Recurring
public class RecurringTaskExample {
static {
LogManager.getRootLogger().setLevel(Level.INFO);
BasicConfigurator.configure();
}
public static void main(String[] args) throws InterruptedException {
recurringSyncTaskExecution();//default
recurringAsyncTaskExecution();
}
private static void recurringSyncTaskExecution() throws InterruptedException {
// Create a recurring task with interval 1000 ms by
// implementing 'performTask' and 'onTaskFailure'
RecurringTask recurringTask = new RecurringTask(1000) {
@Override
public boolean performTask(Object context) {
System.out.println("Performing task");;
return true;
}
@Override
public void onTaskFailure(Object context) {
System.out.println("Performing task failed");;
}
};
//start recurring task
recurringTask.start();
Thread.sleep(4000);
//stop task
recurringTask.stop();
}
private static void recurringAsyncTaskExecution() throws InterruptedException {
// Create a recurring task with interval 1000 ms by
// implementing 'performTask' and 'onTaskFailure'
RecurringTask recurringTask = new RecurringTask(1000) {
@Override
public boolean performTask(Object context) {
System.out.println("Performing task");;
return true;
}
@Override
public void onTaskFailure(Object context) {
System.out.println("Performing task failed");;
}
};
// set async task execution
recurringTask.setTaskExecution(new AsyncTaskExecution(4));
//start recurring task
recurringTask.start();
Thread.sleep(4000);
//stop task
recurringTask.stop();
}
}
Performing task
Performing task
Performing task
Performing task
4005 [main] INFO com.clock.AlarmClock - shutdown()
4008 [main] INFO com.clock.AlarmClock - start() - starting clock Alarmclock
Performing task
Performing task
Performing task
Performing task
8011 [main] INFO com.clock.AlarmClock - shutdown()
Useful methods
- RecurringTask(long wakeupIntervalMilli, boolean registerBeforeExecution, boolean runImmediately) :
- (wakeupIntervalMilli) interval of recurrence
- (registerBeforeExecution) if true next occurrence will be registered before executing current
- (runImmediately) if true will run first execution immediately
- start/stop: to start and stop recurring task
- forceRestart: do not wait for running task
- setTaskExecution(TaskExecution): default is sync task execution [SyncTaskExecution, AsyncTaskExecution]
- setContext(Object): same object will be passed in perform task function
Note: if performTask() returns false then onTaskFailure() will be called
Task
public class TaskExample {
static {
LogManager.getRootLogger().setLevel(Level.INFO);
BasicConfigurator.configure();
}
public static void main(String[] args) {
// Create a task to execute after 1000 ms by
// implementing 'performTask' and 'onTaskFailure'
new Task(1000) {
@Override
public boolean performTask(Object context) {
System.out.println("Perform task");
return true;
}
@Override
public void onTaskFailure(Object context) {
System.out.println("failed execution");
}
}.start();
}
}
Useful methods
- start/stop: to start and stop recurring task
- setTaskExecution(TaskExecution): default is sync task execution [SyncTaskExecution, AsyncTaskExecution]
- forceRestart: do not wait for running task
- setContext(Object): same object will be passed in perform task function
Note: if performTask() returns false then onTaskFailure() will be called