From ffc6db2f2c31045fcb0ebb550ef5633a0dc44d23 Mon Sep 17 00:00:00 2001
From: Krzysztof Magiera <krzysztof@fb.com>
Date: Wed, 28 Oct 2015 14:50:21 -0700
Subject: [PATCH] Add @Nullables to TouchEvent.

Reviewed By: mkonicek

Differential Revision: D2591989

fb-gh-sync-id: 84f139b91ec21e656157a9c54cd616ee15673991
---
 .../react/uimanager/events/TouchEvent.java    | 51 +++++++++++--------
 1 file changed, 29 insertions(+), 22 deletions(-)

diff --git a/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/TouchEvent.java b/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/TouchEvent.java
index 10a4bda3a..407b8c691 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/TouchEvent.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/uimanager/events/TouchEvent.java
@@ -9,9 +9,13 @@
 
 package com.facebook.react.uimanager.events;
 
+import javax.annotation.Nullable;
+
 import android.support.v4.util.Pools;
 import android.view.MotionEvent;
 
+import com.facebook.infer.annotation.Assertions;
+
 /**
  * An event representing the start, end or movement of a touch. Corresponds to a single
  * {@link android.view.MotionEvent}.
@@ -22,8 +26,10 @@ import android.view.MotionEvent;
  */
 public class TouchEvent extends Event<TouchEvent> {
 
+  private static final int TOUCH_EVENTS_POOL_SIZE = 3;
+
   private static final Pools.SynchronizedPool<TouchEvent> EVENTS_POOL =
-      new Pools.SynchronizedPool<>(3);
+      new Pools.SynchronizedPool<>(TOUCH_EVENTS_POOL_SIZE);
 
   public static TouchEvent obtain(
       int viewTag,
@@ -38,57 +44,58 @@ public class TouchEvent extends Event<TouchEvent> {
     return event;
   }
 
-  private MotionEvent mMotionEvent;
-  private TouchEventType mTouchEventType;
+  private @Nullable MotionEvent mMotionEvent;
+  private @Nullable TouchEventType mTouchEventType;
   private short mCoalescingKey;
 
   private TouchEvent() {
   }
 
-  @Override
-  public void onDispose() {
-    mMotionEvent.recycle();
-    mMotionEvent = null;
-    EVENTS_POOL.release(this);
-  }
-
   private void init(
       int viewTag,
       long timestampMs,
       TouchEventType touchEventType,
       MotionEvent motionEventToCopy) {
     super.init(viewTag, timestampMs);
-    mTouchEventType = touchEventType;
-    mMotionEvent = MotionEvent.obtain(motionEventToCopy);
 
     short coalescingKey = 0;
-    int action = (mMotionEvent.getAction() & MotionEvent.ACTION_MASK);
+    int action = (motionEventToCopy.getAction() & MotionEvent.ACTION_MASK);
     switch (action) {
       case MotionEvent.ACTION_DOWN:
-        TouchEventCoalescingKeyHelper.addCoalescingKey(mMotionEvent.getDownTime());
+        TouchEventCoalescingKeyHelper.addCoalescingKey(motionEventToCopy.getDownTime());
         break;
       case MotionEvent.ACTION_UP:
-        TouchEventCoalescingKeyHelper.removeCoalescingKey(mMotionEvent.getDownTime());
+        TouchEventCoalescingKeyHelper.removeCoalescingKey(motionEventToCopy.getDownTime());
         break;
       case MotionEvent.ACTION_POINTER_DOWN:
       case MotionEvent.ACTION_POINTER_UP:
-        TouchEventCoalescingKeyHelper.incrementCoalescingKey(mMotionEvent.getDownTime());
+        TouchEventCoalescingKeyHelper.incrementCoalescingKey(motionEventToCopy.getDownTime());
         break;
       case MotionEvent.ACTION_MOVE:
-        coalescingKey = TouchEventCoalescingKeyHelper.getCoalescingKey(mMotionEvent.getDownTime());
+        coalescingKey =
+            TouchEventCoalescingKeyHelper.getCoalescingKey(motionEventToCopy.getDownTime());
         break;
       case MotionEvent.ACTION_CANCEL:
-        TouchEventCoalescingKeyHelper.removeCoalescingKey(mMotionEvent.getDownTime());
+        TouchEventCoalescingKeyHelper.removeCoalescingKey(motionEventToCopy.getDownTime());
         break;
       default:
         throw new RuntimeException("Unhandled MotionEvent action: " + action);
     }
+    mTouchEventType = touchEventType;
+    mMotionEvent = MotionEvent.obtain(motionEventToCopy);
     mCoalescingKey = coalescingKey;
   }
 
+  @Override
+  public void onDispose() {
+    Assertions.assertNotNull(mMotionEvent).recycle();
+    mMotionEvent = null;
+    EVENTS_POOL.release(this);
+  }
+
   @Override
   public String getEventName() {
-    return mTouchEventType.getJSEventName();
+    return Assertions.assertNotNull(mTouchEventType).getJSEventName();
   }
 
   @Override
@@ -96,7 +103,7 @@ public class TouchEvent extends Event<TouchEvent> {
     // We can coalesce move events but not start/end events. Coalescing move events should probably
     // append historical move data like MotionEvent batching does. This is left as an exercise for
     // the reader.
-    switch (mTouchEventType) {
+    switch (Assertions.assertNotNull(mTouchEventType)) {
       case START:
       case END:
       case CANCEL:
@@ -117,8 +124,8 @@ public class TouchEvent extends Event<TouchEvent> {
   public void dispatch(RCTEventEmitter rctEventEmitter) {
     TouchesHelper.sendTouchEvent(
         rctEventEmitter,
-        mTouchEventType,
+        Assertions.assertNotNull(mTouchEventType),
         getViewTag(),
-        mMotionEvent);
+        Assertions.assertNotNull(mMotionEvent));
   }
 }