B4J Question Strange problem with WebSocket

[vfafou]

Hello!

Trying to send a specific serialised map type from B4J to mobile client (B4A) via web socket connection, an error is occurring at the server side.

The code executing is:

Public Sub SendMessages(Messages As List)
    ws.RunFunction("NewMessage", Messages)
    ws.Flush
End Sub

where Messages List is not empty! It has the item:

(ArrayList) [360, eJwT4WBgYGBkARIhlQWpjMxARpB7ECNItCg/McUvMTeVkQ/IOdd2bvO5vec7zzefbzm3nZELJl+am5RaxMgAMkQAKuZbmpeZnFmQmJNZUskoBNI75dzOc1vP957bcb4VaEYzUD8TUDg5ghGk0QDCiYRyWKGmRKDxofIAxh8uAw==]

with the following structure:

Private peMap As Map
peMap.Initialize
peMap.Put("Type","POK")
peMap.Put("cid"  ,cid) 'where cid = "1007898"

then I call:

Private peMapS As String = Utils.ConvertObjectToString(peMap)
CallSubDelayed3(PushWebShared,"SendClientMessage",peMapS,id)

and the error is:

Error occurred on line: 863
java.lang.RuntimeException: java.lang.NullPointerException
    at anywheresoftware.b4j.object.WebSocket.set(WebSocket.java:142)
    at anywheresoftware.b4j.object.WebSocket.set(WebSocket.java:132)
    at anywheresoftware.b4j.object.WebSocket.RunFunction(WebSocket.java:298)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.shell.Shell.runVoidMethod(Shell.java:676)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:240)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:167)
    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
    at anywheresoftware.b4a.shell.ShellBA.raiseEvent2(ShellBA.java:98)
    at anywheresoftware.b4a.keywords.Common.CallSub4(Common.java:487)
    at anywheresoftware.b4a.keywords.Common.access$0(Common.java:467)
    at anywheresoftware.b4a.keywords.Common$CallSubDelayedHelper.run(Common.java:541)
    at anywheresoftware.b4a.keywords.SimpleMessageLoop.runMessageLoop(SimpleMessageLoop.java:30)
    at anywheresoftware.b4a.StandardBA.startMessageLoop(StandardBA.java:26)
    at anywheresoftware.b4a.shell.ShellBA.startMessageLoop(ShellBA.java:119)
    at anywheresoftware.b4a.keywords.Common.StartMessageLoop(Common.java:153)
    at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:309)
    at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:167)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:91)
    at anywheresoftware.b4a.shell.ShellBA.raiseEvent2(ShellBA.java:98)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:78)
    at rm.rmtunnel.main.main(main.java:29)
Caused by: java.lang.NullPointerException
    at anywheresoftware.b4j.object.WebSocket.set(WebSocket.java:139)
    ... 31 more

Note that other serialised maps are transferred without problems!
Any idea what could cause this?

Thank you in advance!

 

[Erel]

Are you using the latest version of B4J? The line number don't match.

 

[vfafou]

Are you using the latest version of B4J? The line number don't match.

Hello Erel!
Thank you for your response!
I'm using B4J 8.31.

 

[Erel]

Put a breakpoint in PushWebShared SendClientMessage and see what exactly happens there.

 

[vfafou]

Put a breakpoint in PushWebShared SendClientMessage and see what exactly happens there.

Good morning Erel!
I have already done this and the line causing the error is:

ws.RunFunction("NewMessage", Messages)

but Messages List is not empty!

 

[Erel]

My guess is that you are trying to send it to an invalid WebSocket (ws).