While sanity-checking new feature, found the NPE was still being thrown on disconnect. Traced problem to NPE due to no onDisconnect being registered and no check against nulls when invoked. Added wrapping method that is null safe. Since disconnect is different from close, added an onClose event registry and test for that. Checked tests, all pass.

Author: blorp-goes-the-derp

src/main/java/net/twasi/obsremotejava/OBSCommunicator.java

@@ -4,10 +4,7 @@
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
-import net.twasi.obsremotejava.callbacks.Callback;
-import net.twasi.obsremotejava.callbacks.ErrorCallback;
-import net.twasi.obsremotejava.callbacks.StringCallback;
-import net.twasi.obsremotejava.callbacks.VoidCallback;
+import net.twasi.obsremotejava.callbacks.*;
 import net.twasi.obsremotejava.events.EventType;
 import net.twasi.obsremotejava.events.responses.*;
 import net.twasi.obsremotejava.objects.throwables.InvalidResponseTypeError;
@@ -113,6 +110,7 @@ public class OBSCommunicator {
 
     private Callback<GetVersionResponse> onConnect;
     private VoidCallback onDisconnect;
+    private CloseCallback onClose;
     private StringCallback onConnectionFailed;
     private ErrorCallback onError;
 
@@ -162,12 +160,9 @@ public void onError(Session session, Throwable throwable) {
     @OnWebSocketClose
     public void onClose(int statusCode, String reason) {
         log.info(String.format("Connection closed: %d - %s%n", statusCode, reason));
+        runOnDisconnect();
         this.closeLatch.countDown(); // trigger latch
-        try {
-            this.onDisconnect.run();
-        } catch (Throwable t) {
-            log.error("Unable to disconnect OBS Client", t);
-        }
+        runOnClosed(statusCode, reason);
     }
 
     @OnWebSocketConnect
@@ -391,6 +386,8 @@ public void registerOnDisconnect(VoidCallback onDisconnect) {
         this.onDisconnect = onDisconnect;
     }
 
+    public void registerOnClose(CloseCallback closeCallback) { this.onClose = closeCallback; }
+
     public void registerOnConnectionFailed(StringCallback onConnectionFailed) {
         this.onConnectionFailed = onConnectionFailed;
     }
@@ -726,4 +723,34 @@ private void runOnConnect(GetVersionResponse versionInfo) {
             log.error("Unable to run OnConnect callback", t);
         }
     }
+
+    void runOnDisconnect() {
+        log.debug("Running onDisconnect");
+        if (onDisconnect == null) {
+            log.debug("No onDisconnect callback was registered");
+            return;
+        }
+
+        try {
+            onDisconnect.run();
+        } catch (Throwable t) {
+            log.error("Unable to run OnDisconnect callback", t);
+        }
+    }
+
+
+    private void runOnClosed(int statusCode, String reason) {
+        log.debug("Running onClose with statusCode " + statusCode + " and reason: " + reason);
+
+        if(this.onClose == null) {
+            log.debug("No onClose was registered.");
+            return;
+        }
+
+        try {
+            onClose.run(statusCode, reason);
+        } catch (Throwable t) {
+            log.error("Unable to run onClose callback", t);
+        }
+    }
 }

src/main/java/net/twasi/obsremotejava/OBSRemoteController.java

@@ -1,10 +1,7 @@
 package net.twasi.obsremotejava;
 
 import com.google.gson.Gson;
-import net.twasi.obsremotejava.callbacks.Callback;
-import net.twasi.obsremotejava.callbacks.ErrorCallback;
-import net.twasi.obsremotejava.callbacks.StringCallback;
-import net.twasi.obsremotejava.callbacks.VoidCallback;
+import net.twasi.obsremotejava.callbacks.*;
 import net.twasi.obsremotejava.events.responses.*;
 import net.twasi.obsremotejava.objects.throwables.OBSResponseError;
 import net.twasi.obsremotejava.requests.GetCurrentProfile.GetCurrentProfileResponse;
@@ -121,7 +118,7 @@ public void connect() {
     }
 
     public void disconnect() {
-        // wait for closed socket connection
+        // trigger the latch
         try {
             if (debug) {
                 log.debug("Closing connection.");
@@ -131,6 +128,7 @@ public void disconnect() {
             runOnError("Error during closing websocket connection", e);
         }
 
+        // stop the client if it isn't already stopped or stopping
         if (!client.isStopped() && !client.isStopping()) {
             try {
                 if (debug) {
@@ -169,6 +167,10 @@ public void registerConnectionFailedCallback(StringCallback onConnectionFailed)
         communicator.registerOnConnectionFailed(onConnectionFailed);
     }
 
+    public void registerCloseCallback(CloseCallback closeCallback) {
+        communicator.registerOnClose(closeCallback);
+    }
+
     public void registerRecordingStartedCallback(VoidCallback onRecordingStarted) {
         communicator.registerOnRecordingStarted(onRecordingStarted);
     }
@@ -404,4 +406,5 @@ private void runOnConnectionFailed(String message, Throwable throwable) {
             log.error("Unable to run OnConnectionFailed callback", e);
         }
     }
+
 }

src/main/java/net/twasi/obsremotejava/callbacks/CloseCallback.java

@@ -0,0 +1,5 @@
+package net.twasi.obsremotejava.callbacks;
+
+public interface CloseCallback {
+    void run(int statusCode, String reason);
+}

src/main/java/net/twasi/obsremotejava/requests/GetVersion/GetVersionResponse.java

@@ -16,4 +16,12 @@ public String getObsWebsocketVersion() {
     public String getObsStudioVersion() {
         return obsStudioVersion;
     }
+
+    @Override
+    public String toString() {
+        return "GetVersionResponse{" +
+                "obsWebsocketVersion='" + obsWebsocketVersion + '\'' +
+                ", obsStudioVersion='" + obsStudioVersion + '\'' +
+                '}';
+    }
 }

src/test/java/net/twasi/obsremotejava/test/OBSRemoteControllerUnsecuredIT.java

@@ -110,6 +110,41 @@ void testConnectAndDisconnect() {
         }
     }
 
+    @Test
+    void testCloseCallback() {
+
+        // Given a controller that connects successfully
+        final OBSRemoteController controller = new OBSRemoteController(obsAddress, true,
+                obsPassword, true);
+
+        if (controller.isFailed()) {
+            fail("Failed to connect to websocket");
+        }
+
+        // When we register a Close callback
+        AtomicReference<Boolean> testSuccessful = new AtomicReference<>(Boolean.FALSE);
+        AtomicReference<String> testFailedReason = new AtomicReference<>();
+
+        controller.registerCloseCallback((int statusCode, String reason) -> testSuccessful.set(Boolean.TRUE));
+
+        // When we disconnect
+        try {
+            controller.disconnect();
+            controller.await();
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+
+        // Then the close callback should have been called
+        if (testFailedReason.get() != null) {
+            fail(testFailedReason.get());
+        }
+
+        if (!testSuccessful.get()) {
+            fail("Disconnect didn't work");
+        }
+    }
+
     @Test
     void disconnectShouldNotHaveErrorsWhenNoConnectDisconnectCallbacksRegistered() {
         AtomicReference<String> testFailedReason = new AtomicReference<>();