Use getReactApplicationContextIfActiveOrWarn in modules that access JS or Native modules through ReactApplicationContext

Summary:
In D18032458 we introduce `getReactApplicationContextIfActiveOrWarn`. In this diff, modules that access a JS or Native module through ReactApplicationContext need to check if the CatalystInstance is still alive before continuing.

Changelog: [Internal]

Reviewed By: furdei

Differential Revision: D18032788

fbshipit-source-id: 5152783afd0b93b8ce0970fe4a509ea71396a54a

ReactAndroid/src/main/java/com/facebook/react/animated/NativeAnimatedModule.java

@@ -116,10 +116,14 @@ public class NativeAnimatedModule extends ReactContextBaseJavaModule
 
   @Override
   public void initialize() {
-    ReactApplicationContext reactCtx = getReactApplicationContext();
-    UIManagerModule uiManager = reactCtx.getNativeModule(UIManagerModule.class);
-    reactCtx.addLifecycleEventListener(this);
-    uiManager.addUIManagerListener(this);
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, "initialize");
+
+    if (reactApplicationContext != null) {
+      UIManagerModule uiManager = reactApplicationContext.getNativeModule(UIManagerModule.class);
+      reactApplicationContext.addLifecycleEventListener(this);
+      uiManager.addUIManagerListener(this);
+    }
   }
 
   @Override
@@ -175,9 +179,13 @@ public class NativeAnimatedModule extends ReactContextBaseJavaModule
 
   private NativeAnimatedNodesManager getNodesManager() {
     if (mNodesManager == null) {
-      UIManagerModule uiManager =
-          getReactApplicationContext().getNativeModule(UIManagerModule.class);
-      mNodesManager = new NativeAnimatedNodesManager(uiManager);
+      ReactApplicationContext reactApplicationContext =
+          getReactApplicationContextIfActiveOrWarn(NAME, "getNodesManager");
+
+      if (reactApplicationContext != null) {
+        UIManagerModule uiManager = reactApplicationContext.getNativeModule(UIManagerModule.class);
+        mNodesManager = new NativeAnimatedNodesManager(uiManager);
+      }
     }
 
     return mNodesManager;
@@ -219,9 +227,15 @@ public class NativeAnimatedModule extends ReactContextBaseJavaModule
             WritableMap onAnimatedValueData = Arguments.createMap();
             onAnimatedValueData.putInt("tag", tag);
             onAnimatedValueData.putDouble("value", value);
-            getReactApplicationContext()
-                .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
-                .emit("onAnimatedValueUpdate", onAnimatedValueData);
+
+            ReactApplicationContext reactApplicationContext =
+                getReactApplicationContextIfActiveOrWarn(
+                    NAME, "startListeningToAnimatedNodeValue.onValueUpdate");
+            if (reactApplicationContext != null) {
+              reactApplicationContext
+                  .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
+                  .emit("onAnimatedValueUpdate", onAnimatedValueData);
+            }
           }
         };
 

ReactAndroid/src/main/java/com/facebook/react/devsupport/JSCHeapCapture.java

@@ -19,6 +19,8 @@ import java.io.File;
 // requires it to already be initialized, thus we eagerly initialize this module
 @ReactModule(name = "JSCHeapCapture", needsEagerInit = true)
 public class JSCHeapCapture extends ReactContextBaseJavaModule {
+  public static final String TAG = JSCHeapCapture.class.getSimpleName();
+
   public interface HeapCapture extends JavaScriptModule {
     void captureHeap(String path);
   }
@@ -54,13 +56,18 @@ public class JSCHeapCapture extends ReactContextBaseJavaModule {
     File f = new File(path + "/capture.json");
     f.delete();
 
-    HeapCapture heapCapture = getReactApplicationContext().getJSModule(HeapCapture.class);
-    if (heapCapture == null) {
-      callback.onFailure(new CaptureException("Heap capture js module not registered."));
-      return;
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(TAG, "captureHeap");
+
+    if (reactApplicationContext != null) {
+      HeapCapture heapCapture = reactApplicationContext.getJSModule(HeapCapture.class);
+      if (heapCapture == null) {
+        callback.onFailure(new CaptureException("Heap capture js module not registered."));
+        return;
+      }
+      mCaptureInProgress = callback;
+      heapCapture.captureHeap(f.getPath());
     }
-    mCaptureInProgress = callback;
-    heapCapture.captureHeap(f.getPath());
   }
 
   @ReactMethod

ReactAndroid/src/main/java/com/facebook/react/devsupport/JSDevSupport.java

@@ -20,7 +20,6 @@ import java.util.Map;
 
 @ReactModule(name = JSDevSupport.MODULE_NAME)
 public class JSDevSupport extends ReactContextBaseJavaModule {
-
   public static final String MODULE_NAME = "JSDevSupport";
 
   public static final int ERROR_CODE_EXCEPTION = 0;
@@ -55,8 +54,14 @@ public class JSDevSupport extends ReactContextBaseJavaModule {
   }
 
   public synchronized void getJSHierarchy(int reactTag, DevSupportCallback callback) {
-    JSDevSupportModule jsDevSupportModule =
-        getReactApplicationContext().getJSModule(JSDevSupportModule.class);
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(MODULE_NAME, "getJSHierarchy");
+
+    JSDevSupportModule jsDevSupportModule = null;
+    if (reactApplicationContext != null) {
+      jsDevSupportModule = reactApplicationContext.getJSModule(JSDevSupportModule.class);
+    }
+
     if (jsDevSupportModule == null) {
       callback.onFailure(
           ERROR_CODE_EXCEPTION,

ReactAndroid/src/main/java/com/facebook/react/modules/accessibilityinfo/AccessibilityInfoModule.java

@@ -116,18 +116,29 @@ public class AccessibilityInfoModule extends ReactContextBaseJavaModule
 
     if (mReduceMotionEnabled != isReduceMotionEnabled) {
       mReduceMotionEnabled = isReduceMotionEnabled;
-      getReactApplicationContext()
-          .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
-          .emit(REDUCE_MOTION_EVENT_NAME, mReduceMotionEnabled);
+
+      ReactApplicationContext reactApplicationContext =
+          getReactApplicationContextIfActiveOrWarn(NAME, "updateAndSendReduceMotionChangeEvent");
+      if (reactApplicationContext != null) {
+        reactApplicationContext
+            .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
+            .emit(REDUCE_MOTION_EVENT_NAME, mReduceMotionEnabled);
+      }
     }
   }
 
   private void updateAndSendTouchExplorationChangeEvent(boolean enabled) {
     if (mTouchExplorationEnabled != enabled) {
       mTouchExplorationEnabled = enabled;
-      getReactApplicationContext()
-          .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
-          .emit(TOUCH_EXPLORATION_EVENT_NAME, mTouchExplorationEnabled);
+
+      ReactApplicationContext reactApplicationContext =
+          getReactApplicationContextIfActiveOrWarn(
+              NAME, "updateAndSendTouchExplorationChangeEvent");
+      if (reactApplicationContext != null) {
+        getReactApplicationContext()
+            .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
+            .emit(TOUCH_EXPLORATION_EVENT_NAME, mTouchExplorationEnabled);
+      }
     }
   }
 

ReactAndroid/src/main/java/com/facebook/react/modules/appearance/AppearanceModule.java

@@ -21,6 +21,7 @@ import com.facebook.react.modules.core.DeviceEventManagerModule.RCTDeviceEventEm
 /** Module that exposes the user's preferred color scheme. For API >= 29. */
 @ReactModule(name = AppearanceModule.NAME)
 public class AppearanceModule extends ReactContextBaseJavaModule {
+
   public static final String NAME = "Appearance";
 
   private static final String APPEARANCE_CHANGED_EVENT_NAME = "appearanceChanged";
@@ -85,8 +86,13 @@ public class AppearanceModule extends ReactContextBaseJavaModule {
     WritableMap appearancePreferences = Arguments.createMap();
     appearancePreferences.putString("colorScheme", colorScheme);
 
-    getReactApplicationContext()
-        .getJSModule(RCTDeviceEventEmitter.class)
-        .emit(APPEARANCE_CHANGED_EVENT_NAME, appearancePreferences);
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, "emitAppearanceChanged");
+
+    if (reactApplicationContext != null) {
+      reactApplicationContext
+          .getJSModule(RCTDeviceEventEmitter.class)
+          .emit(APPEARANCE_CHANGED_EVENT_NAME, appearancePreferences);
+    }
   }
 }

ReactAndroid/src/main/java/com/facebook/react/modules/blob/BlobModule.java

@@ -286,37 +286,61 @@ public class BlobModule extends ReactContextBaseJavaModule {
     return type;
   }
 
-  private WebSocketModule getWebSocketModule() {
-    return getReactApplicationContext().getNativeModule(WebSocketModule.class);
+  private WebSocketModule getWebSocketModule(String reason) {
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, reason);
+
+    if (reactApplicationContext != null) {
+      return reactApplicationContext.getNativeModule(WebSocketModule.class);
+    }
+
+    return null;
   }
 
   @ReactMethod
   public void addNetworkingHandler() {
-    NetworkingModule networkingModule =
-        getReactApplicationContext().getNativeModule(NetworkingModule.class);
-    networkingModule.addUriHandler(mNetworkingUriHandler);
-    networkingModule.addRequestBodyHandler(mNetworkingRequestBodyHandler);
-    networkingModule.addResponseHandler(mNetworkingResponseHandler);
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, "addNetworkingHandler");
+
+    if (reactApplicationContext != null) {
+      NetworkingModule networkingModule =
+          reactApplicationContext.getNativeModule(NetworkingModule.class);
+      networkingModule.addUriHandler(mNetworkingUriHandler);
+      networkingModule.addRequestBodyHandler(mNetworkingRequestBodyHandler);
+      networkingModule.addResponseHandler(mNetworkingResponseHandler);
+    }
   }
 
   @ReactMethod
   public void addWebSocketHandler(final int id) {
-    getWebSocketModule().setContentHandler(id, mWebSocketContentHandler);
+    WebSocketModule webSocketModule = getWebSocketModule("addWebSocketHandler");
+
+    if (webSocketModule != null) {
+      webSocketModule.setContentHandler(id, mWebSocketContentHandler);
+    }
   }
 
   @ReactMethod
   public void removeWebSocketHandler(final int id) {
-    getWebSocketModule().setContentHandler(id, null);
+    WebSocketModule webSocketModule = getWebSocketModule("removeWebSocketHandler");
+
+    if (webSocketModule != null) {
+      webSocketModule.setContentHandler(id, null);
+    }
   }
 
   @ReactMethod
   public void sendOverSocket(ReadableMap blob, int id) {
-    byte[] data = resolve(blob.getString("blobId"), blob.getInt("offset"), blob.getInt("size"));
+    WebSocketModule webSocketModule = getWebSocketModule("sendOverSocket");
 
-    if (data != null) {
-      getWebSocketModule().sendBinary(ByteString.of(data), id);
-    } else {
-      getWebSocketModule().sendBinary((ByteString) null, id);
+    if (webSocketModule != null) {
+      byte[] data = resolve(blob.getString("blobId"), blob.getInt("offset"), blob.getInt("size"));
+
+      if (data != null) {
+        webSocketModule.sendBinary(ByteString.of(data), id);
+      } else {
+        webSocketModule.sendBinary((ByteString) null, id);
+      }
     }
   }
 

ReactAndroid/src/main/java/com/facebook/react/modules/blob/FileReaderModule.java

@@ -30,16 +30,29 @@ public class FileReaderModule extends ReactContextBaseJavaModule {
     return NAME;
   }
 
-  private BlobModule getBlobModule() {
-    return getReactApplicationContext().getNativeModule(BlobModule.class);
+  private BlobModule getBlobModule(String reason) {
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, reason);
+
+    if (reactApplicationContext != null) {
+      return reactApplicationContext.getNativeModule(BlobModule.class);
+    }
+
+    return null;
   }
 
   @ReactMethod
   public void readAsText(ReadableMap blob, String encoding, Promise promise) {
+    BlobModule blobModule = getBlobModule("readAsText");
+
+    if (blobModule == null) {
+      promise.reject(
+          new IllegalStateException("Could not get BlobModule from ReactApplicationContext"));
+      return;
+    }
 
     byte[] bytes =
-        getBlobModule()
-            .resolve(blob.getString("blobId"), blob.getInt("offset"), blob.getInt("size"));
+        blobModule.resolve(blob.getString("blobId"), blob.getInt("offset"), blob.getInt("size"));
 
     if (bytes == null) {
       promise.reject(ERROR_INVALID_BLOB, "The specified blob is invalid");
@@ -55,9 +68,16 @@ public class FileReaderModule extends ReactContextBaseJavaModule {
 
   @ReactMethod
   public void readAsDataURL(ReadableMap blob, Promise promise) {
+    BlobModule blobModule = getBlobModule("readAsDataURL");
+
+    if (blobModule == null) {
+      promise.reject(
+          new IllegalStateException("Could not get BlobModule from ReactApplicationContext"));
+      return;
+    }
+
     byte[] bytes =
-        getBlobModule()
-            .resolve(blob.getString("blobId"), blob.getInt("offset"), blob.getInt("size"));
+        blobModule.resolve(blob.getString("blobId"), blob.getInt("offset"), blob.getInt("size"));
 
     if (bytes == null) {
       promise.reject(ERROR_INVALID_BLOB, "The specified blob is invalid");

ReactAndroid/src/main/java/com/facebook/react/modules/core/DeviceEventManagerModule.java

@@ -47,16 +47,26 @@ public class DeviceEventManagerModule extends ReactContextBaseJavaModule {
 
   /** Sends an event to the JS instance that the hardware back has been pressed. */
   public void emitHardwareBackPressed() {
-    getReactApplicationContext()
-        .getJSModule(RCTDeviceEventEmitter.class)
-        .emit("hardwareBackPress", null);
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, "emitHardwareBackPressed");
+
+    if (reactApplicationContext != null) {
+      reactApplicationContext
+          .getJSModule(RCTDeviceEventEmitter.class)
+          .emit("hardwareBackPress", null);
+    }
   }
 
   /** Sends an event to the JS instance that a new intent was received. */
   public void emitNewIntentReceived(Uri uri) {
-    WritableMap map = Arguments.createMap();
-    map.putString("url", uri.toString());
-    getReactApplicationContext().getJSModule(RCTDeviceEventEmitter.class).emit("url", map);
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(NAME, "emitHardwareBackPressed");
+
+    if (reactApplicationContext != null) {
+      WritableMap map = Arguments.createMap();
+      map.putString("url", uri.toString());
+      reactApplicationContext.getJSModule(RCTDeviceEventEmitter.class).emit("url", map);
+    }
   }
 
   /**
@@ -65,6 +75,9 @@ public class DeviceEventManagerModule extends ReactContextBaseJavaModule {
    */
   @ReactMethod
   public void invokeDefaultBackPressHandler() {
+    // There should be no need to check if the catalyst instance is alive. After initialization
+    // the thread instances cannot be null, and scheduling on a thread after ReactApplicationContext
+    // teardown is a noop.
     getReactApplicationContext().runOnUiQueueThread(mInvokeDefaultBackPressRunnable);
   }
 

ReactAndroid/src/main/java/com/facebook/react/modules/core/TimingModule.java

@@ -25,17 +25,32 @@ public final class TimingModule extends ReactContextBaseJavaModule
   public class BridgeTimerManager implements JavaScriptTimerManager {
     @Override
     public void callTimers(WritableArray timerIDs) {
-      getReactApplicationContext().getJSModule(JSTimers.class).callTimers(timerIDs);
+      ReactApplicationContext reactApplicationContext =
+          getReactApplicationContextIfActiveOrWarn(NAME, "callTimers");
+
+      if (reactApplicationContext != null) {
+        reactApplicationContext.getJSModule(JSTimers.class).callTimers(timerIDs);
+      }
     }
 
     @Override
     public void callIdleCallbacks(double frameTime) {
-      getReactApplicationContext().getJSModule(JSTimers.class).callIdleCallbacks(frameTime);
+      ReactApplicationContext reactApplicationContext =
+          getReactApplicationContextIfActiveOrWarn(NAME, "callIdleCallbacks");
+
+      if (reactApplicationContext != null) {
+        reactApplicationContext.getJSModule(JSTimers.class).callIdleCallbacks(frameTime);
+      }
     }
 
     @Override
     public void emitTimeDriftWarning(String warningMessage) {
-      getReactApplicationContext().getJSModule(JSTimers.class).emitTimeDriftWarning(warningMessage);
+      ReactApplicationContext reactApplicationContext =
+          getReactApplicationContextIfActiveOrWarn(NAME, "emitTimeDriftWarning");
+
+      if (reactApplicationContext != null) {
+        reactApplicationContext.getJSModule(JSTimers.class).emitTimeDriftWarning(warningMessage);
+      }
     }
   }
 

ReactAndroid/src/main/java/com/facebook/react/modules/debug/DevSettingsModule.java

@@ -92,9 +92,15 @@ public class DevSettingsModule extends ReactContextBaseJavaModule {
           public void onOptionSelected() {
             WritableMap data = Arguments.createMap();
             data.putString("title", title);
-            getReactApplicationContext()
-                .getJSModule(RCTDeviceEventEmitter.class)
-                .emit("didPressMenuItem", data);
+
+            ReactApplicationContext reactApplicationContext =
+                getReactApplicationContextIfActiveOrWarn(NAME, "onOptionSelected");
+
+            if (reactApplicationContext != null) {
+              reactApplicationContext
+                  .getJSModule(RCTDeviceEventEmitter.class)
+                  .emit("didPressMenuItem", data);
+            }
           }
         });
   }

ReactAndroid/src/main/java/com/facebook/react/modules/network/NetworkingModule.java

@@ -249,7 +249,10 @@ public final class NetworkingModule extends ReactContextBaseJavaModule {
           withCredentials);
     } catch (Throwable th) {
       FLog.e(TAG, "Failed to send url request: " + url, th);
-      ResponseUtil.onRequestError(getEventEmitter(), requestId, th.getMessage(), th);
+      final RCTDeviceEventEmitter eventEmitter = getEventEmitter("sendRequest error");
+      if (eventEmitter != null) {
+        ResponseUtil.onRequestError(eventEmitter, requestId, th.getMessage(), th);
+      }
     }
   }
 
@@ -264,7 +267,7 @@ public final class NetworkingModule extends ReactContextBaseJavaModule {
       final boolean useIncrementalUpdates,
       int timeout,
       boolean withCredentials) {
-    final RCTDeviceEventEmitter eventEmitter = getEventEmitter();
+    final RCTDeviceEventEmitter eventEmitter = getEventEmitter("sendRequestInternal");
 
     try {
       Uri uri = Uri.parse(url);
@@ -664,7 +667,7 @@ public final class NetworkingModule extends ReactContextBaseJavaModule {
 
   private @Nullable MultipartBody.Builder constructMultipartBody(
       ReadableArray body, String contentType, int requestId) {
-    RCTDeviceEventEmitter eventEmitter = getEventEmitter();
+    RCTDeviceEventEmitter eventEmitter = getEventEmitter("constructMultipartBody");
     MultipartBody.Builder multipartBuilder = new MultipartBody.Builder();
     multipartBuilder.setType(MediaType.parse(contentType));
 
@@ -750,7 +753,14 @@ public final class NetworkingModule extends ReactContextBaseJavaModule {
     return headersBuilder.build();
   }
 
-  private RCTDeviceEventEmitter getEventEmitter() {
-    return getReactApplicationContext().getJSModule(RCTDeviceEventEmitter.class);
+  private RCTDeviceEventEmitter getEventEmitter(String reason) {
+    ReactApplicationContext reactApplicationContext =
+        getReactApplicationContextIfActiveOrWarn(TAG, reason);
+
+    if (reactApplicationContext != null) {
+      return getReactApplicationContext().getJSModule(RCTDeviceEventEmitter.class);
+    }
+
+    return null;
   }
 }

ReactAndroid/src/main/java/com/facebook/react/modules/network/ResponseUtil.java

@@ -7,6 +7,7 @@
 
 package com.facebook.react.modules.network;
 
+import androidx.annotation.Nullable;
 import com.facebook.react.bridge.Arguments;
 import com.facebook.react.bridge.WritableArray;
 import com.facebook.react.bridge.WritableMap;
@@ -16,55 +17,69 @@ import java.net.SocketTimeoutException;
 /** Util methods to send network responses to JS. */
 public class ResponseUtil {
   public static void onDataSend(
-      RCTDeviceEventEmitter eventEmitter, int requestId, long progress, long total) {
+      @Nullable RCTDeviceEventEmitter eventEmitter, int requestId, long progress, long total) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushInt((int) progress);
     args.pushInt((int) total);
-    eventEmitter.emit("didSendNetworkData", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didSendNetworkData", args);
+    }
   }
 
   public static void onIncrementalDataReceived(
-      RCTDeviceEventEmitter eventEmitter, int requestId, String data, long progress, long total) {
+      @Nullable RCTDeviceEventEmitter eventEmitter,
+      int requestId,
+      String data,
+      long progress,
+      long total) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushString(data);
     args.pushInt((int) progress);
     args.pushInt((int) total);
 
-    eventEmitter.emit("didReceiveNetworkIncrementalData", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didReceiveNetworkIncrementalData", args);
+    }
   }
 
   public static void onDataReceivedProgress(
-      RCTDeviceEventEmitter eventEmitter, int requestId, long progress, long total) {
+      @Nullable RCTDeviceEventEmitter eventEmitter, int requestId, long progress, long total) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushInt((int) progress);
     args.pushInt((int) total);
 
-    eventEmitter.emit("didReceiveNetworkDataProgress", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didReceiveNetworkDataProgress", args);
+    }
   }
 
   public static void onDataReceived(
-      RCTDeviceEventEmitter eventEmitter, int requestId, String data) {
+      @Nullable RCTDeviceEventEmitter eventEmitter, int requestId, String data) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushString(data);
 
-    eventEmitter.emit("didReceiveNetworkData", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didReceiveNetworkData", args);
+    }
   }
 
   public static void onDataReceived(
-      RCTDeviceEventEmitter eventEmitter, int requestId, WritableMap data) {
+      @Nullable RCTDeviceEventEmitter eventEmitter, int requestId, WritableMap data) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushMap(data);
 
-    eventEmitter.emit("didReceiveNetworkData", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didReceiveNetworkData", args);
+    }
   }
 
   public static void onRequestError(
-      RCTDeviceEventEmitter eventEmitter, int requestId, String error, Throwable e) {
+      @Nullable RCTDeviceEventEmitter eventEmitter, int requestId, String error, Throwable e) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushString(error);
@@ -73,19 +88,23 @@ public class ResponseUtil {
       args.pushBoolean(true); // last argument is a time out boolean
     }
 
-    eventEmitter.emit("didCompleteNetworkResponse", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didCompleteNetworkResponse", args);
+    }
   }
 
-  public static void onRequestSuccess(RCTDeviceEventEmitter eventEmitter, int requestId) {
+  public static void onRequestSuccess(@Nullable RCTDeviceEventEmitter eventEmitter, int requestId) {
     WritableArray args = Arguments.createArray();
     args.pushInt(requestId);
     args.pushNull();
 
-    eventEmitter.emit("didCompleteNetworkResponse", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didCompleteNetworkResponse", args);
+    }
   }
 
   public static void onResponseReceived(
-      RCTDeviceEventEmitter eventEmitter,
+      @Nullable RCTDeviceEventEmitter eventEmitter,
       int requestId,
       int statusCode,
       WritableMap headers,
@@ -96,6 +115,8 @@ public class ResponseUtil {
     args.pushMap(headers);
     args.pushString(url);
 
-    eventEmitter.emit("didReceiveNetworkResponse", args);
+    if (eventEmitter != null) {
+      eventEmitter.emit("didReceiveNetworkResponse", args);
+    }
   }
 }