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diff --git a/java/com/android/dialer/common/concurrent/DialerUiTaskFragment.java b/java/com/android/dialer/common/concurrent/DialerUiTaskFragment.java
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+++ b/java/com/android/dialer/common/concurrent/DialerUiTaskFragment.java
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2017 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.dialer.common.concurrent;
+
+import android.app.Fragment;
+import android.app.FragmentManager;
+import android.os.AsyncTask;
+import android.os.Bundle;
+import android.support.annotation.MainThread;
+import android.support.annotation.Nullable;
+import com.android.dialer.common.Assert;
+import com.android.dialer.common.LogUtil;
+import com.android.dialer.common.concurrent.AsyncTaskExecutors.SimpleAsyncTaskExecutor;
+import com.android.dialer.common.concurrent.DialerExecutor.FailureListener;
+import com.android.dialer.common.concurrent.DialerExecutor.SuccessListener;
+import com.android.dialer.common.concurrent.DialerExecutor.Worker;
+import java.util.concurrent.ExecutorService;
+
+/**
+ * Do not use this class directly. Instead use {@link DialerExecutors}.
+ *
+ * @param <InputT> the type of the object sent to the task upon execution
+ * @param <OutputT> the type of the result of the background computation
+ */
+public final class DialerUiTaskFragment<InputT, OutputT> extends Fragment {
+
+  private String taskId;
+  private Worker<InputT, OutputT> worker;
+  private SuccessListener<OutputT> successListener;
+  private FailureListener failureListener;
+
+  private AsyncTaskExecutor serialExecutor = AsyncTaskExecutors.createAsyncTaskExecutor();
+  private AsyncTaskExecutor parallelExecutor = AsyncTaskExecutors.createThreadPoolExecutor();
+
+  /**
+   * Creates a new {@link DialerUiTaskFragment} or gets an existing one in the event that a
+   * configuration change occurred while the previous activity's task was still running. Must be
+   * called from onCreate of your activity or fragment.
+   *
+   * @param taskId used for the headless fragment ID and task ID
+   * @param worker a function executed on a worker thread which accepts an {@link InputT} and
+   *     returns an {@link OutputT}. It should ideally not be an inner class of your
+   *     activity/fragment (meaning it should not be a lambda, anonymous, or non-static) but it can
+   *     be a static nested class. The static nested class should not contain any reference to UI,
+   *     including any activity or fragment or activity context, though it may reference some
+   *     threadsafe system objects such as the application context.
+   * @param successListener a function executed on the main thread upon task success. There are no
+   *     restraints on this as it is executed on the main thread, so lambdas, anonymous, or inner
+   *     classes of your activity or fragment are all fine.
+   * @param failureListener a function executed on the main thread upon task failure. The exception
+   *     is already logged so this can often be a no-op. There are no restraints on this as it is
+   *     executed on the main thread, so lambdas, anonymous, or inner classes of your activity or
+   *     fragment are all fine.
+   * @param <InputT> the type of the object sent to the task upon execution
+   * @param <OutputT> the type of the result of the background computation
+   * @return a {@link DialerUiTaskFragment} which may be used to call the "execute*" methods
+   */
+  @MainThread
+  static <InputT, OutputT> DialerUiTaskFragment<InputT, OutputT> create(
+      FragmentManager fragmentManager,
+      String taskId,
+      Worker<InputT, OutputT> worker,
+      SuccessListener<OutputT> successListener,
+      FailureListener failureListener,
+      @Nullable ExecutorService serialExecutorService,
+      @Nullable ExecutorService parallelExecutorService) {
+    Assert.isMainThread();
+
+    DialerUiTaskFragment<InputT, OutputT> fragment =
+        (DialerUiTaskFragment<InputT, OutputT>) fragmentManager.findFragmentByTag(taskId);
+
+    if (fragment == null) {
+      LogUtil.i("DialerUiTaskFragment.create", "creating new DialerUiTaskFragment");
+      fragment = new DialerUiTaskFragment<>();
+      fragmentManager.beginTransaction().add(fragment, taskId).commit();
+    }
+    fragment.taskId = taskId;
+    fragment.worker = worker;
+    fragment.successListener = successListener;
+    fragment.failureListener = failureListener;
+    if (serialExecutorService != null) {
+      fragment.serialExecutor = new SimpleAsyncTaskExecutor(serialExecutorService);
+    }
+    if (parallelExecutorService != null) {
+      fragment.parallelExecutor = new SimpleAsyncTaskExecutor(parallelExecutorService);
+    }
+    return fragment;
+  }
+
+  @Override
+  public void onCreate(Bundle savedInstanceState) {
+    super.onCreate(savedInstanceState);
+    setRetainInstance(true);
+  }
+
+  @Override
+  public void onDetach() {
+    super.onDetach();
+    LogUtil.enterBlock("DialerUiTaskFragment.onDetach");
+    taskId = null;
+    successListener = null;
+    failureListener = null;
+  }
+
+  void executeSerial(InputT input) {
+    serialExecutor.submit(taskId, new InternalTask(), input);
+  }
+
+  void executeParallel(InputT input) {
+    parallelExecutor.submit(taskId, new InternalTask(), input);
+  }
+
+  void executeOnCustomExecutor(ExecutorService executor, InputT input) {
+    new SimpleAsyncTaskExecutor(executor).submit(taskId, new InternalTask(), input);
+  }
+
+  private final class InternalTask extends AsyncTask<InputT, Void, InternalTaskResult<OutputT>> {
+
+    @SafeVarargs
+    @Override
+    protected final InternalTaskResult<OutputT> doInBackground(InputT... params) {
+      try {
+        return new InternalTaskResult<>(null, worker.doInBackground(params[0]));
+      } catch (Throwable throwable) {
+        LogUtil.e("InternalTask.doInBackground", "task failed", throwable);
+        return new InternalTaskResult<>(throwable, null);
+      }
+    }
+
+    @Override
+    protected void onPostExecute(InternalTaskResult<OutputT> result) {
+      if (result.throwable != null) {
+        if (failureListener == null) {
+          LogUtil.i("InternalTask.onPostExecute", "task failed but UI is dead");
+        } else {
+          failureListener.onFailure(result.throwable);
+        }
+      } else if (successListener == null) {
+        LogUtil.i("InternalTask.onPostExecute", "task succeeded but UI is dead");
+      } else {
+        successListener.onSuccess(result.result);
+      }
+    }
+  }
+
+  private static class InternalTaskResult<OutputT> {
+
+    private final Throwable throwable;
+    private final OutputT result;
+
+    InternalTaskResult(Throwable throwable, OutputT result) {
+      this.throwable = throwable;
+      this.result = result;
+    }
+  }
+}