Watchdog (MyTISM API Documentation)

java.lang.Object
- de.ipcon.tools.concurrent.Watchdog

```
public class Watchdog
extends java.lang.Object
```
Manages a scheduled task that triggers after a specified delay, with methods to reset, prolong, or cancel the task execution.
The task will execute once the specified delay has passed unless the watchdog is "fed" (reset) or its timeout is "delayed". Additionally, the watchdog task can be cancelled entirely.

This implementation uses a ReentrantLock to protect the critical sections where task cancellation and rescheduling happen, ensuring thread-safe execution even when multiple threads concurrently call methods like feed() and feedTreat(long, TimeUnit).

A ScheduledExecutorService with a fixed thread pool size of 2 is used to schedule the tasks. This ensures concurrent execution of watchdog tasks, allowing multiple watchdogs to operate independently and execute tasks in parallel if needed.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`callOff()` Cancels the current watchdog task if it exists.
`boolean`	`feed()` Reschedules the watchdog with the initially configured delay.
`boolean`	`feedTreat(int oneTimeDelaySeconds)` Prolongs the watchdog with a one-time delay, specified in seconds.
`boolean`	`feedTreat(long oneTimeDelay, java.util.concurrent.TimeUnit timeUnit)` Prolongs the watchdog with a one-time delay.
`static void`	`main(java.lang.String[] args)` Main method to demonstrate the use of the Watchdog.
`static Watchdog`	`of(java.lang.Runnable task, int delaySeconds)` Factory method to create a new instance of the `Watchdog`.
`static Watchdog`	`of(java.lang.Runnable task, long delay, java.util.concurrent.TimeUnit timeUnit)` Factory method to create a new instance of the `Watchdog`.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - of
```
public static Watchdog of(java.lang.Runnable task,
                          long delay,
                          java.util.concurrent.TimeUnit timeUnit)
```
    Factory method to create a new instance of the Watchdog.
    
    Parameters:
    
    task - The task to execute when the watchdog triggers.
    
    delay - The initial delay before the watchdog triggers.
    
    timeUnit - The time unit of the delay.
    
    Returns:
    
    A new Watchdog instance.
  - of
```
public static Watchdog of(java.lang.Runnable task,
                          int delaySeconds)
```
    Factory method to create a new instance of the Watchdog.
    
    Parameters:
    
    task - The task to execute when the watchdog triggers.
    
    delaySeconds - The initial delay before the watchdog triggers, in seconds.
    
    Returns:
    
    A new Watchdog instance.
  - callOff
```
public boolean callOff()
```
    Cancels the current watchdog task if it exists.
    This method cancels the currently scheduled task, if it is still pending execution. It ensures that no task will be executed once the watchdog is called off.
    
    Returns:
    
    true if the task was cancelled, false if there was no task to cancel.
  - feed
```
public boolean feed()
```
    Reschedules the watchdog with the initially configured delay.
    This method resets the watchdog, essentially "feeding" it, by canceling the existing task and scheduling a new task with the original delay. The task will trigger after the initial delay unless rescheduled again.
    
    Returns:
    
    true if the task was successfully cancelled and rescheduled, false if no task was cancelled.
  - feedTreat
```
public boolean feedTreat(int oneTimeDelaySeconds)
```
    Prolongs the watchdog with a one-time delay, specified in seconds.
    This method provides the watchdog with a special "treat" by delaying its next trigger with a one-time delay, specified in seconds. The watchdog will revert to its original triggering schedule when "fed" via feed() normally again. This is useful for situations where a longer operation needs to be performed without causing the watchdog to bark prematurely.
    
    Parameters:
    
    oneTimeDelaySeconds - The one-time delay, in seconds, to apply to the watchdog.
    
    Returns:
    
    true if the watchdog's triggering was successfully delayed, false otherwise.
  - feedTreat
```
public boolean feedTreat(long oneTimeDelay,
                         java.util.concurrent.TimeUnit timeUnit)
```
    Prolongs the watchdog with a one-time delay.
    This method provides the watchdog with a special "treat" by delaying its next trigger with a one-time delay. The watchdog will revert to its original triggering schedule when "fed" via feed() normally again. This is useful for situations where a longer operation needs to be performed without causing the watchdog to bark prematurely.
    
    Parameters:
    
    oneTimeDelay - The one-time delay to apply to the watchdog.
    
    timeUnit - The time unit of the delay.
    
    Returns:
    
    true if the watchdog's triggering was successfully delayed, false otherwise.
  - main
```
public static void main(java.lang.String[] args)
                 throws java.lang.InterruptedException
```
    Main method to demonstrate the use of the Watchdog.
    This example shows how to create a Watchdog, "feed" it (reset its timer), "delay" its barking (prolong its timer) and finally let it bark (trigger the task).
    
    Parameters:
    
    args - command-line arguments
    
    Throws:
    
    java.lang.InterruptedException - if interrupted while waiting for tasks

Class Watchdog

Method Summary

Methods inherited from class java.lang.Object

Method Detail

of

of

callOff

feed

feedTreat

feedTreat

main