Package com.google.common.util.concurrent

Interface TimeLimiter

All Known Implementing Classes:

FakeTimeLimiter, SimpleTimeLimiter

@Beta
@DoNotMock("Use FakeTimeLimiter")
@GwtIncompatible
public interface TimeLimiter

Imposes a time limit on method calls.

Since:

1.0

Author:

Kevin Bourrillion, Jens Nyman

Method Summary

Modifier and Type	Method	Description
<T extends @Nullable Object> T	callUninterruptiblyWithTimeout(Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit)	Invokes a specified Callable, timing out after the specified time limit.
<T extends @Nullable Object> T	callWithTimeout(Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit)	Invokes a specified Callable, timing out after the specified time limit.
<T> T	newProxy(T target, Class<T> interfaceType, long timeoutDuration, TimeUnit timeoutUnit)	Returns an instance of interfaceType that delegates all method calls to the target object, enforcing the specified time limit on each call.
void	runUninterruptiblyWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)	Invokes a specified Runnable, timing out after the specified time limit.
void	runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)	Invokes a specified Runnable, timing out after the specified time limit.

Method Detail

newProxy

<T> T newProxy(T target,
               Class<T> interfaceType,
               long timeoutDuration,
               TimeUnit timeoutUnit)

Returns an instance of interfaceType that delegates all method calls to the target object, enforcing the specified time limit on each call. This time-limited delegation is also performed for calls to Object.equals(java.lang.Object), Object.hashCode(), and Object.toString().

If the target method call finishes before the limit is reached, the return value or exception is propagated to the caller exactly as-is. If, on the other hand, the time limit is reached, the proxy will attempt to abort the call to the target, and will throw an UncheckedTimeoutException to the caller.

It is important to note that the primary purpose of the proxy object is to return control to the caller when the timeout elapses; aborting the target method call is of secondary concern. The particular nature and strength of the guarantees made by the proxy is implementation-dependent. However, it is important that each of the methods on the target object behaves appropriately when its thread is interrupted.

For example, to return the value of target.someMethod(), but substitute DEFAULT_VALUE if this method call takes over 50 ms, you can use this code:

   TimeLimiter limiter = . . .;
   TargetType proxy = limiter.newProxy(
       target, TargetType.class, 50, TimeUnit.MILLISECONDS);
   try {
     return proxy.someMethod();
   } catch (UncheckedTimeoutException e) {
     return DEFAULT_VALUE;
   }
 

Parameters:

target - the object to proxy

interfaceType - the interface you wish the returned proxy to implement

timeoutDuration - with timeoutUnit, the maximum length of time that callers are willing to wait on each method call to the proxy

timeoutUnit - with timeoutDuration, the maximum length of time that callers are willing to wait on each method call to the proxy

Returns:

a time-limiting proxy

Throws:

IllegalArgumentException - if interfaceType is a regular class, enum, or annotation type, rather than an interface

callWithTimeout

@CanIgnoreReturnValue
<T extends @Nullable Object> T callWithTimeout(Callable<T> callable,
                                               long timeoutDuration,
                                               TimeUnit timeoutUnit)
                                        throws TimeoutException,
                                               InterruptedException,
                                               ExecutionException

Invokes a specified Callable, timing out after the specified time limit. If the target method call finishes before the limit is reached, the return value or a wrapped exception is propagated. If, on the other hand, the time limit is reached, we attempt to abort the call to the target, and throw a TimeoutException to the caller.

Parameters:

callable - the Callable to execute

timeoutDuration - with timeoutUnit, the maximum length of time to wait

timeoutUnit - with timeoutDuration, the maximum length of time to wait

Returns:

the result returned by the Callable

Throws:

TimeoutException - if the time limit is reached

InterruptedException - if the current thread was interrupted during execution

ExecutionException - if callable throws a checked exception

UncheckedExecutionException - if callable throws a RuntimeException

ExecutionError - if callable throws an Error

Since:

22.0

callUninterruptiblyWithTimeout

@CanIgnoreReturnValue
<T extends @Nullable Object> T callUninterruptiblyWithTimeout(Callable<T> callable,
                                                              long timeoutDuration,
                                                              TimeUnit timeoutUnit)
                                                       throws TimeoutException,
                                                              ExecutionException

Invokes a specified Callable, timing out after the specified time limit. If the target method call finishes before the limit is reached, the return value or a wrapped exception is propagated. If, on the other hand, the time limit is reached, we attempt to abort the call to the target, and throw a TimeoutException to the caller.

The difference with callWithTimeout(Callable, long, TimeUnit) is that this method will ignore interrupts on the current thread.

Parameters:

callable - the Callable to execute

timeoutDuration - with timeoutUnit, the maximum length of time to wait

timeoutUnit - with timeoutDuration, the maximum length of time to wait

Returns:

the result returned by the Callable

Throws:

TimeoutException - if the time limit is reached

ExecutionException - if callable throws a checked exception

UncheckedExecutionException - if callable throws a RuntimeException

ExecutionError - if callable throws an Error

Since:

22.0

runWithTimeout

void runWithTimeout(Runnable runnable,
                    long timeoutDuration,
                    TimeUnit timeoutUnit)
             throws TimeoutException,
                    InterruptedException

Invokes a specified Runnable, timing out after the specified time limit. If the target method run finishes before the limit is reached, this method returns or a wrapped exception is propagated. If, on the other hand, the time limit is reached, we attempt to abort the run, and throw a TimeoutException to the caller.

Parameters:

runnable - the Runnable to execute

timeoutDuration - with timeoutUnit, the maximum length of time to wait

timeoutUnit - with timeoutDuration, the maximum length of time to wait

Throws:

TimeoutException - if the time limit is reached

InterruptedException - if the current thread was interrupted during execution

UncheckedExecutionException - if runnable throws a RuntimeException

ExecutionError - if runnable throws an Error

Since:

22.0

runUninterruptiblyWithTimeout

void runUninterruptiblyWithTimeout(Runnable runnable,
                                   long timeoutDuration,
                                   TimeUnit timeoutUnit)
                            throws TimeoutException

Invokes a specified Runnable, timing out after the specified time limit. If the target method run finishes before the limit is reached, this method returns or a wrapped exception is propagated. If, on the other hand, the time limit is reached, we attempt to abort the run, and throw a TimeoutException to the caller.

The difference with runWithTimeout(Runnable, long, TimeUnit) is that this method will ignore interrupts on the current thread.

Parameters:

runnable - the Runnable to execute

timeoutDuration - with timeoutUnit, the maximum length of time to wait

timeoutUnit - with timeoutDuration, the maximum length of time to wait

Throws:

TimeoutException - if the time limit is reached

UncheckedExecutionException - if runnable throws a RuntimeException

ExecutionError - if runnable throws an Error

Since:

22.0