Fixed compile error in AOSP due to use of guava 23 API.

Futures.submitAsync is V23 and AOSP is currently stuck at V20.

This is just a completely non-sensical dummy implementation of DialerFutureSerializer until we can figure out what to do.

Test: tap
PiperOrigin-RevId: 178323108
Change-Id: I1dc2c8ddfa7ef3e15170543dadefbe4fc2e19226

1 files changed, 7 insertions, 66 deletions

diff --git a/java/com/android/dialer/common/concurrent/DialerFutureSerializer.java b/java/com/android/dialer/common/concurrent/DialerFutureSerializer.java
index 2629abbbe..de37a2915 100644
--- a/java/com/android/dialer/common/concurrent/DialerFutureSerializer.java
+++ b/java/com/android/dialer/common/concurrent/DialerFutureSerializer.java
@@ -16,83 +16,24 @@
 
 package com.android.dialer.common.concurrent;
 
-import static com.google.common.util.concurrent.Futures.immediateCancelledFuture;
-import static com.google.common.util.concurrent.Futures.immediateFuture;
-import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
-
 import com.google.common.util.concurrent.AsyncCallable;
-import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
-import com.google.common.util.concurrent.SettableFuture;
-import java.util.concurrent.Callable;
 import java.util.concurrent.Executor;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicReference;
 
 /**
  * Serializes execution of a set of operations. This class guarantees that a submitted callable will
  * not be called before previously submitted callables have completed.
  */
 public final class DialerFutureSerializer {
-  /** This reference acts as a pointer tracking the head of a linked list of ListenableFutures. */
-  private final AtomicReference<ListenableFuture<?>> ref =
-      new AtomicReference<>(immediateFuture(null));
 
   /** Enqueues a task to run when the previous task (if any) completes. */
-  public <T> ListenableFuture<T> submit(final Callable<T> callable, Executor executor) {
-    return submitAsync(() -> immediateFuture(callable.call()), executor);
-  }
-
-  /**
-   * Enqueues a task to run when the previous task (if any) completes.
-   *
-   * <p>Cancellation does not propagate from the output future to the future returned from {@code
-   * callable}, but if the output future is cancelled before {@link AsyncCallable#call()} is
-   * invoked, {@link AsyncCallable#call()} will not be invoked.
-   */
   public <T> ListenableFuture<T> submitAsync(final AsyncCallable<T> callable, Executor executor) {
-    AtomicBoolean wasCancelled = new AtomicBoolean(false);
-    final AsyncCallable<T> task =
-        () -> {
-          if (wasCancelled.get()) {
-            return immediateCancelledFuture();
-          }
-          return callable.call();
-        };
-    /*
-     * Three futures are at play here:
-     * taskFuture is the future that comes from the callable.
-     * newFuture is the future we use to track the serialization of our task.
-     * oldFuture is the previous task's newFuture.
-     *
-     * newFuture is guaranteed to only complete once all tasks previously submitted to this instance
-     * once the futures returned from those submissions have completed.
-     */
-    final SettableFuture<Object> newFuture = SettableFuture.create();
-
-    final ListenableFuture<?> oldFuture = ref.getAndSet(newFuture);
-
-    // Invoke our task once the previous future completes.
-    final ListenableFuture<T> taskFuture =
-        Futures.nonCancellationPropagating(
-            Futures.submitAsync(task, runnable -> oldFuture.addListener(runnable, executor)));
-    // newFuture's lifetime is determined by taskFuture, unless taskFuture is cancelled, in which
-    // case it falls back to oldFuture's. This is to ensure that if the future we return is
-    // cancelled, we don't begin execution of the next task until after oldFuture completes.
-    taskFuture.addListener(
-        () -> {
-          if (taskFuture.isCancelled()) {
-            // Since the value of oldFuture can only ever be immediateFuture(null) or setFuture of a
-            // future that eventually came from immediateFuture(null), this doesn't leak throwables
-            // or completion values.
-            wasCancelled.set(true);
-            newFuture.setFuture(oldFuture);
-          } else {
-            newFuture.set(null);
-          }
-        },
-        directExecutor());
-
-    return taskFuture;
+    // TODO(zachh): This is just a dummy implementation until we fix guava API level issues.
+    try {
+      return callable.call();
+    } catch (Exception e) {
+      e.printStackTrace();
+    }
+    return null;
   }
 }