| /* |
| * Copyright (C) 2011 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 com.android.volley.toolbox; |
| |
| import com.android.volley.Request; |
| import com.android.volley.Response; |
| import com.android.volley.VolleyError; |
| |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.Future; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.TimeoutException; |
| |
| /** |
| * A Future that represents a Volley request. |
| * |
| * Used by providing as your response and error listeners. For example: |
| * <pre> |
| * RequestFuture<JSONObject> future = RequestFuture.newFuture(); |
| * MyRequest request = new MyRequest(URL, future, future); |
| * |
| * // If you want to be able to cancel the request: |
| * future.setRequest(requestQueue.add(request)); |
| * |
| * // Otherwise: |
| * requestQueue.add(request); |
| * |
| * try { |
| * JSONObject response = future.get(); |
| * // do something with response |
| * } catch (InterruptedException e) { |
| * // handle the error |
| * } catch (ExecutionException e) { |
| * // handle the error |
| * } |
| * </pre> |
| * |
| * @param <T> The type of parsed response this future expects. |
| */ |
| public class RequestFuture<T> implements Future<T>, Response.Listener<T>, |
| Response.ErrorListener { |
| private Request<?> mRequest; |
| private boolean mResultReceived = false; |
| private T mResult; |
| private VolleyError mException; |
| |
| public static <E> RequestFuture<E> newFuture() { |
| return new RequestFuture<E>(); |
| } |
| |
| private RequestFuture() {} |
| |
| public void setRequest(Request<?> request) { |
| mRequest = request; |
| } |
| |
| @Override |
| public synchronized boolean cancel(boolean mayInterruptIfRunning) { |
| if (mRequest == null) { |
| return false; |
| } |
| |
| if (!isDone()) { |
| mRequest.cancel(); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| @Override |
| public T get() throws InterruptedException, ExecutionException { |
| try { |
| return doGet(null); |
| } catch (TimeoutException e) { |
| throw new AssertionError(e); |
| } |
| } |
| |
| @Override |
| public T get(long timeout, TimeUnit unit) |
| throws InterruptedException, ExecutionException, TimeoutException { |
| return doGet(TimeUnit.MILLISECONDS.convert(timeout, unit)); |
| } |
| |
| private synchronized T doGet(Long timeoutMs) |
| throws InterruptedException, ExecutionException, TimeoutException { |
| if (mException != null) { |
| throw new ExecutionException(mException); |
| } |
| |
| if (mResultReceived) { |
| return mResult; |
| } |
| |
| if (timeoutMs == null) { |
| wait(0); |
| } else if (timeoutMs > 0) { |
| wait(timeoutMs); |
| } |
| |
| if (mException != null) { |
| throw new ExecutionException(mException); |
| } |
| |
| if (!mResultReceived) { |
| throw new TimeoutException(); |
| } |
| |
| return mResult; |
| } |
| |
| @Override |
| public boolean isCancelled() { |
| if (mRequest == null) { |
| return false; |
| } |
| return mRequest.isCanceled(); |
| } |
| |
| @Override |
| public synchronized boolean isDone() { |
| return mResultReceived || mException != null || isCancelled(); |
| } |
| |
| @Override |
| public synchronized void onResponse(T response) { |
| mResultReceived = true; |
| mResult = response; |
| notifyAll(); |
| } |
| |
| @Override |
| public synchronized void onErrorResponse(VolleyError error) { |
| mException = error; |
| notifyAll(); |
| } |
| } |
| |