TimerService (Flink : 2.0-preview1 API)

Type Parameters:

K - Type of the key

All Known Implementing Classes:

DefaultTimerService
```
public interface TimerService<K>
```
Service to register timeouts for a given key. The timeouts are identified by a ticket so that newly registered timeouts for the same key can be distinguished from older timeouts.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`isValid(K key, UUID ticket)`	Check whether the timeout for the given key and ticket is still valid (not yet unregistered and not yet overwritten).
`void`	`registerTimeout(K key, long delay, TimeUnit unit)`	Register a timeout for the given key which shall occur in the given delay.
`void`	`start(TimeoutListener<K> timeoutListener)`	Starts this timer service.
`void`	`stop()`	Stops this timer service.
`void`	`unregisterTimeout(K key)`	Unregister the timeout for the given key.

- Method Detail
  - start
```
void start(TimeoutListener<K> timeoutListener)
```
    Starts this timer service.
    
    Parameters:
    
    timeoutListener - listener for timeouts that have fired
  - stop
```
void stop()
```
    Stops this timer service.
  - registerTimeout
```
void registerTimeout(K key,
                     long delay,
                     TimeUnit unit)
```
    Register a timeout for the given key which shall occur in the given delay.
    
    Parameters:
    
    key - for which to register the timeout
    
    delay - until the timeout
    
    unit - of the timeout delay
  - unregisterTimeout
```
void unregisterTimeout(K key)
```
    Unregister the timeout for the given key.
    
    Parameters:
    
    key - for which to unregister the timeout
  - isValid
```
boolean isValid(K key,
                UUID ticket)
```
    Check whether the timeout for the given key and ticket is still valid (not yet unregistered and not yet overwritten).
    
    Parameters:
    
    key - for which to check the timeout
    
    ticket - of the timeout
    
    Returns:
    
    True if the timeout ticket is still valid; otherwise false