Package com.google.api.core

Class ApiFutures

java.lang.Object
com.google.api.core.ApiFutures
public final class ApiFutures extends Object
Static utility methods for the ApiFuture interface.

  • Method Details

    • addCallback

      @Deprecated public static <V> void addCallback(ApiFuture<V> future, ApiFutureCallback<? super V> callback)
      Deprecated.
      Use the overload that requires an executor. For identical behavior, pass MoreExecutors.directExecutor(), but consider whether another executor would be safer.
      Registers a callback to be run when the ApiFuture's computation is complete or, if the computation is already complete, immediately.
      Parameters:
      future - The future attach the callback to
      callback - The callback to invoke when future is completed

    • addCallback

      public static <V> void addCallback(ApiFuture<V> future, ApiFutureCallback<? super V> callback, Executor executor)
      Registers a callback to be run when the ApiFuture's computation is complete or, if the computation is already complete, immediately.

      Note that this method is a delegate of Futures.addCallback(ListenableFuture, FutureCallback, Executor).

      Parameters:
      future - The future attach the callback to
      callback - The callback to invoke when future is completed
      executor - The executor to run callback when the future completes
      See Also:
      • Futures.addCallback(ListenableFuture, FutureCallback, Executor)

    • catching

      @Deprecated public static <V, X extends Throwable> ApiFuture<V> catching(ApiFuture<? extends V> input, Class<X> exceptionType, ApiFunction<? super X,? extends V> callback)
      Deprecated.
      Use the overload that requires an executor. For identical behavior, pass MoreExecutors.directExecutor(), but consider whether another executor would be safer.
      Returns an ApiFuture whose result is taken from the given primary input or, if the primary input fails with the given exceptionType, from the result provided by the callback.
      Parameters:
      input - The primary input ApiFuture
      exceptionType - The exception type that triggers use of fallback
      callback - The ApiFunction to be called if input fails with the expected exception type
      Returns:
      A future whose result is taken either from the given input or by the callback

    • catching

      public static <V, X extends Throwable> ApiFuture<V> catching(ApiFuture<? extends V> input, Class<X> exceptionType, ApiFunction<? super X,? extends V> callback, Executor executor)
      Returns an ApiFuture whose result is taken from the given primary input or, if the primary input fails with the given exceptionType, from the result provided by the callback.

      Note that this method is a delegate of Futures.catching(ListenableFuture, Class, Function, Executor).

      Parameters:
      input - The primary input ApiFuture
      exceptionType - The exception type that triggers use of fallback
      callback - The ApiFunction to be called if input fails with the expected exception type
      executor - The executor that runs fallback if input fails
      Returns:
      A future whose result is taken either from the given input or by the callback
      See Also:
      • Futures.catching(ListenableFuture, Class, Function, Executor)

    • catchingAsync

      public static <V, X extends Throwable> ApiFuture<V> catchingAsync(ApiFuture<V> input, Class<X> exceptionType, ApiAsyncFunction<? super X,V> callback, Executor executor)
      Returns a ApiFuture whose result is taken from the given primary input or, if the primary input fails with the given exceptionType, from the result provided by the callback.

      Note that this method is a delegate of Futures.catchingAsync(ListenableFuture, Class, AsyncFunction, Executor)

      Parameters:
      input - The primary input ApiFuture
      exceptionType - The exception type that triggers use of fallback.
      callback - The ApiAsyncFunction to be called if input fails with the expected * exception type.
      executor - The executor that runs fallback if input fails
      Returns:
      A future whose result is taken either from the given input or by the callback
      See Also:
      • Futures.catchingAsync(ListenableFuture, Class, AsyncFunction, Executor)

    • immediateFuture

      public static <V> ApiFuture<V> immediateFuture(V value)
      Creates a ApiFuture which has its value set immediately upon construction.

      Note that this method is a delegate of Futures.immediateFuture(Object).

      Parameters:
      value - The value set to the ApiFuture upon construction
      Returns:
      A future that holds value
      See Also:
      • Futures.immediateFuture(Object)

    • immediateFailedFuture

      public static <V> ApiFuture<V> immediateFailedFuture(Throwable throwable)
      Returns a ApiFuture which has an exception set immediately upon construction.

      Note that this method is a delegate of Futures.immediateFailedFuture(Throwable).

      Parameters:
      throwable - The exception set to the ApiFuture upon construction
      Returns:
      A future that holds an exception
      See Also:
      • Futures.immediateFailedFuture(Throwable)

    • immediateCancelledFuture

      public static <V> ApiFuture<V> immediateCancelledFuture()
      Creates a ApiFuture which is cancelled immediately upon construction, so that isCancelled() always returns true.

      Note that this method is a delegate of Futures.immediateCancelledFuture().

      Returns:
      A cancelled future
      See Also:
      • Futures.immediateCancelledFuture()

    • transform

      @Deprecated public static <V, X> ApiFuture<X> transform(ApiFuture<? extends V> input, ApiFunction<? super V,? extends X> function)
      Deprecated.
      Use the overload that requires an executor. For identical behavior, pass MoreExecutors.directExecutor(), but consider whether another executor would be safer.
      Returns a new ApiFuture whose result is derived from the result of the given ApiFuture.
      Parameters:
      input - The future to transform
      function - A Function to transform the results of the provided future to the results of the returned future
      Returns:
      A future that holds result of the transformation

    • transform

      public static <V, X> ApiFuture<X> transform(ApiFuture<? extends V> input, ApiFunction<? super V,? extends X> function, Executor executor)
      Returns a new ApiFuture whose result is derived from the result of the given ApiFuture.

      Note that this method is a delegate of Futures.transform(ListenableFuture, Function, Executor).

      Parameters:
      input - The future to transform
      function - A Function to transform the results of the provided future to the results of the returned future.
      executor - Executor to run the function in.
      Returns:
      A future that holds result of the transformation
      See Also:
      • Futures.transform(ListenableFuture, Function, Executor)

    • allAsList

      public static <V> ApiFuture<List<V>> allAsList(Iterable<? extends ApiFuture<? extends V>> futures)
      Creates a new ApiFuture whose value is a list containing the values of all its input futures, if all succeed.

      The list of results is in the same order as the input list.

      Note that this method is a delegate of Futures.allAsList(Iterable).

      Parameters:
      futures - Futures to combine
      Returns:
      A future that provides a list of the results of the component futures
      See Also:
      • Futures.allAsList(Iterable)

    • successfulAsList

      @BetaApi public static <V> ApiFuture<List<V>> successfulAsList(Iterable<? extends ApiFuture<? extends V>> futures)
      Creates a new ApiFuture whose value is a list containing the values of all its successful input futures. The list of results is in the same order as the input list, and if any of the provided futures fails or is canceled, its corresponding position will contain null (which is indistinguishable from the future having a successful value of null).

      The list of results is in the same order as the input list.

      Note that this method is a delegate of Futures.successfulAsList(Iterable).

      Parameters:
      futures - Futures to combine
      Returns:
      A future that provides a list of the results of the component futures
      See Also:
      • Futures.successfulAsList(Iterable)

    • transformAsync

      @Deprecated public static <I, O> ApiFuture<O> transformAsync(ApiFuture<I> input, ApiAsyncFunction<I,O> function)
      Deprecated.
      Use transformAsync(ApiFuture, ApiAsyncFunction, Executor), the overload that requires an executor. For identical behavior, pass MoreExecutors.directExecutor(), but consider whether another executor would be safer.
      Returns a new ApiFuture whose result is asynchronously derived from the result of the given ApiFuture. If the given Future fails, the returned ApiFuture fails with the same exception (and the function is not invoked).
      Parameters:
      input - The future to transform
      function - A function to transform the result of the input future to the result of the output future
      Returns:
      A future that holds result of the function (if the input succeeded) or the original input's failure (if not)

    • transformAsync

      public static <I, O> ApiFuture<O> transformAsync(ApiFuture<I> input, ApiAsyncFunction<I,O> function, Executor executor)
      Returns a new ApiFuture whose result is asynchronously derived from the result of the given ApiFuture. If the given Future fails, the returned ApiFuture fails with the same exception (and the function is not invoked).

      Note that this method is a delegate of Futures.transformAsync(ListenableFuture, AsyncFunction, Executor).

      Parameters:
      input - The future to transform
      function - A function to transform the result of the input future to the result of the output future
      executor - Executor to run the function in.
      Returns:
      A future that holds result of the function (if the input succeeded) or the original input's failure (if not)
      See Also:
      • Futures.transformAsync(ListenableFuture, AsyncFunction, Executor)