android.accounts.AccountManagerFuture Maven / Gradle / Ivy
Show all versions of android-all Show documentation
/*
* Copyright (C) 2009 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.accounts;
import java.util.concurrent.TimeUnit;
import java.io.IOException;
/**
* A AccountManagerFuture represents the result of an asynchronous
* {@link AccountManager} call. Methods are provided to check if the computation is
* complete, to wait for its completion, and to retrieve the result of
* the computation. The result can only be retrieved using method
* get when the computation has completed, blocking if
* necessary until it is ready. Cancellation is performed by the
* cancel method. Additional methods are provided to
* determine if the task completed normally or was cancelled. Once a
* computation has completed, the computation cannot be cancelled.
* If you would like to use a Future for the sake
* of cancellability but not provide a usable result, you can
* declare types of the form Future<?> and
* return null as a result of the underlying task.
*/
public interface AccountManagerFuture {
/**
* Attempts to cancel execution of this task. This attempt will
* fail if the task has already completed, has already been cancelled,
* or could not be cancelled for some other reason. If successful,
* and this task has not started when cancel is called,
* this task should never run. If the task has already started,
* then the mayInterruptIfRunning parameter determines
* whether the thread executing this task should be interrupted in
* an attempt to stop the task.
*
* After this method returns, subsequent calls to {@link #isDone} will
* always return true. Subsequent calls to {@link #isCancelled}
* will always return true if this method returned true.
*
* @param mayInterruptIfRunning true if the thread executing this
* task should be interrupted; otherwise, in-progress tasks are allowed
* to complete
* @return false if the task could not be cancelled,
* typically because it has already completed normally;
* true otherwise
*/
boolean cancel(boolean mayInterruptIfRunning);
/**
* Returns true if this task was cancelled before it completed
* normally.
*
* @return true if this task was cancelled before it completed
*/
boolean isCancelled();
/**
* Returns true if this task completed.
*
* Completion may be due to normal termination, an exception, or
* cancellation -- in all of these cases, this method will return
* true.
*
* @return true if this task completed
*/
boolean isDone();
/**
* Accessor for the future result the {@link AccountManagerFuture} represents. This
* call will block until the result is available. In order to check if the result is
* available without blocking, one may call {@link #isDone()} and {@link #isCancelled()}.
* If the request that generated this result fails or is canceled then an exception
* will be thrown rather than the call returning normally.
* @return the actual result
* @throws android.accounts.OperationCanceledException if the request was canceled for any
* reason (including if it is forbidden
* by policy to modify an account (of that type))
* @throws android.accounts.AuthenticatorException if there was an error communicating with
* the authenticator or if the authenticator returned an invalid response
* @throws java.io.IOException if the authenticator returned an error response that indicates
* that it encountered an IOException while communicating with the authentication server
*/
V getResult() throws OperationCanceledException, IOException, AuthenticatorException;
/**
* Accessor for the future result the {@link AccountManagerFuture} represents. This
* call will block until the result is available. In order to check if the result is
* available without blocking, one may call {@link #isDone()} and {@link #isCancelled()}.
* If the request that generated this result fails or is canceled then an exception
* will be thrown rather than the call returning normally. If a timeout is specified then
* the request will automatically be canceled if it does not complete in that amount of time.
* @param timeout the maximum time to wait
* @param unit the time unit of the timeout argument. This must not be null.
* @return the actual result
* @throws android.accounts.OperationCanceledException if the request was canceled for any
* reason
* @throws android.accounts.AuthenticatorException if there was an error communicating with
* the authenticator or if the authenticator returned an invalid response
* @throws java.io.IOException if the authenticator returned an error response that indicates
* that it encountered an IOException while communicating with the authentication server
*/
V getResult(long timeout, TimeUnit unit)
throws OperationCanceledException, IOException, AuthenticatorException;
}