Class SimpleTimeLimiter

java.lang.Object
com.google.common.util.concurrent.SimpleTimeLimiter
All Implemented Interfaces:
TimeLimiter
@GwtIncompatible public final class SimpleTimeLimiter extends Object implements TimeLimiter
A TimeLimiter that runs method calls in the background using an ExecutorService. If the time limit expires for a given method call, the thread running the call will be interrupted.
Since:
1.0
Author:
Kevin Bourrillion, Jens Nyman

  • Method Details

    • create

      public static SimpleTimeLimiter create(ExecutorService executor)
      Creates a TimeLimiter instance using the given executor service to execute method calls.

      Warning: using a bounded executor may be counterproductive! If the thread pool fills up, any time callers spend waiting for a thread may count toward their time limit, and in this case the call may even time out before the target method is ever invoked.

      Parameters:
      executor - the ExecutorService that will execute the method calls on the target objects; for example, a Executors.newCachedThreadPool().
      Since:
      22.0

    • newProxy

      public <T> T newProxy(T target, Class<T> interfaceType, long timeoutDuration, TimeUnit timeoutUnit)
      Description copied from interface: TimeLimiter
      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;
   }
      Specified by:
      newProxy in interface TimeLimiter
      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

    • callWithTimeout

      @CanIgnoreReturnValue public <T extends @Nullable Object> T callWithTimeout(Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException, InterruptedException, ExecutionException
      Description copied from interface: TimeLimiter
      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.
      Specified by:
      callWithTimeout in interface TimeLimiter
      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

    • callUninterruptiblyWithTimeout

      @CanIgnoreReturnValue public <T extends @Nullable Object> T callUninterruptiblyWithTimeout(Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException, ExecutionException
      Description copied from interface: TimeLimiter
      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 TimeLimiter.callWithTimeout(Callable, long, TimeUnit) is that this method will ignore interrupts on the current thread.

      Specified by:
      callUninterruptiblyWithTimeout in interface TimeLimiter
      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

    • runWithTimeout

      public void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException, InterruptedException
      Description copied from interface: TimeLimiter
      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.
      Specified by:
      runWithTimeout in interface TimeLimiter
      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

    • runUninterruptiblyWithTimeout

      public void runUninterruptiblyWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException
      Description copied from interface: TimeLimiter
      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 TimeLimiter.runWithTimeout(Runnable, long, TimeUnit) is that this method will ignore interrupts on the current thread.

      Specified by:
      runUninterruptiblyWithTimeout in interface TimeLimiter
      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