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diff --git a/core/src/main/java/com/android/volley/toolbox/RequestFuture.java b/core/src/main/java/com/android/volley/toolbox/RequestFuture.java
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+/*
+ * 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 android.os.SystemClock;
+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.
+ *
+ * <p>Used by providing as your response and error listeners. For example:
+ *
+ * <pre>
+ * RequestFuture&lt;JSONObject&gt; 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<>();
+ }
+
+ 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(/* timeoutMs= */ 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) {
+ while (!isDone()) {
+ wait(0);
+ }
+ } else if (timeoutMs > 0) {
+ long nowMs = SystemClock.uptimeMillis();
+ long deadlineMs = nowMs + timeoutMs;
+ while (!isDone() && nowMs < deadlineMs) {
+ wait(deadlineMs - nowMs);
+ nowMs = SystemClock.uptimeMillis();
+ }
+ }
+
+ 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();
+ }
+}