Java Question ba.raiseEvent ERROR

package com.sample;
import android.accessibilityservice.AccessibilityService;
import android.view.accessibility.AccessibilityEvent;
import anywheresoftware.b4a.BA;
import anywheresoftware.b4a.BA.Events;
import anywheresoftware.b4a.BA.ShortName;
import anywheresoftware.b4a.BA.Version;
@ShortName("ASB")
@Version(1.0f)
@Events(values={"accessibilityevent (event As string)"})  
public class ASBWrapper extends AccessibilityService{
    BA ba;
    String eventName;
    AccessibilityService as;
    public void Initialize(BA ba, String EventName) {
        this.ba = ba;
        this.eventName = EventName.toLowerCase(BA.cul);
    }
   
    @Override
    public void onAccessibilityEvent(AccessibilityEvent arg0) {
        // TODO Auto-generated method stub
        BA.Log("access");
        ba.raiseEvent(this,eventName + "_accessibilityevent", "test");  
    }
    @Override
    public void onInterrupt() {
        // TODO Auto-generated method stub
        BA.Log("interrupt");
    }
   
}

#Region  Service Attributes
    #StartAtBoot: False
#End Region

Sub Process_Globals
    'These global variables will be declared once when the application starts.
    'These variables can be accessed from all modules.
    Dim asb As ASB
End Sub

Sub Service_Create
 asb.Initialize("asb")
End Sub

Sub Service_Start (StartingIntent As Intent)

End Sub

Sub asb_AccessibilityEvent(event As String)
    Log(event)
End Sub
Sub Service_Destroy

End Sub

*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
** Activity (main) Resume **
*** Service (mm) Create ***
** Service (mm) Start **
** Activity (main) Pause, UserClosed = false **
access
java.lang.NullPointerException
    at com.sample.ASBWrapper.onAccessibilityEvent(ASBWrapper.java:34)
    at android.accessibilityservice.AccessibilityService$1.onAccessibilityEvent(AccessibilityService.java:518)
    at android.accessibilityservice.AccessibilityService$IAccessibilityServiceClientWrapper.executeMessage(AccessibilityService.java:584)
    at com.android.internal.os.HandlerCaller$MyHandler.handleMessage(HandlerCaller.java:61)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:137)
    at android.app.ActivityThread.main(ActivityThread.java:4960)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:511)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805)
    at dalvik.system.NativeStart.main(Native Method)