| /* |
| * 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 <tt>AccountManagerFuture</tt> 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 |
| * <tt>get</tt> when the computation has completed, blocking if |
| * necessary until it is ready. Cancellation is performed by the |
| * <tt>cancel</tt> 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 <tt>Future</tt> for the sake |
| * of cancellability but not provide a usable result, you can |
| * declare types of the form <tt>Future<?></tt> and |
| * return <tt>null</tt> as a result of the underlying task. |
| */ |
| public interface AccountManagerFuture<V> { |
| /** |
| * 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 <tt>cancel</tt> is called, |
| * this task should never run. If the task has already started, |
| * then the <tt>mayInterruptIfRunning</tt> parameter determines |
| * whether the thread executing this task should be interrupted in |
| * an attempt to stop the task. |
| * |
| * <p>After this method returns, subsequent calls to {@link #isDone} will |
| * always return <tt>true</tt>. Subsequent calls to {@link #isCancelled} |
| * will always return <tt>true</tt> if this method returned <tt>true</tt>. |
| * |
| * @param mayInterruptIfRunning <tt>true</tt> if the thread executing this |
| * task should be interrupted; otherwise, in-progress tasks are allowed |
| * to complete |
| * @return <tt>false</tt> if the task could not be cancelled, |
| * typically because it has already completed normally; |
| * <tt>true</tt> otherwise |
| */ |
| boolean cancel(boolean mayInterruptIfRunning); |
| |
| /** |
| * Returns <tt>true</tt> if this task was cancelled before it completed |
| * normally. |
| * |
| * @return <tt>true</tt> if this task was cancelled before it completed |
| */ |
| boolean isCancelled(); |
| |
| /** |
| * Returns <tt>true</tt> if this task completed. |
| * |
| * Completion may be due to normal termination, an exception, or |
| * cancellation -- in all of these cases, this method will return |
| * <tt>true</tt>. |
| * |
| * @return <tt>true</tt> 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; |
| } |