I have complied 3 files (SerialBean.java;SerialBuffer.java;ReaderSerial.java) as my package successfully, it is named serial. The package extends javax.comm.*; I wanna do some serial work.
Then I maked an application :SerialExample1
----------------------------SerialExmaple1.java-----------------------------
It is good enough to deliver the
String "Hi,Chrono".
Then I maked another windows application :SerialExample2
It is a bad code!!! I compiled them seccessfully but It can't work .The
java system gave
some wrong messages
-----------------------------------------------------------------------------------
Exception occurred during event dispatching:java.lang.NullPointerExceptionat serial.SerialBean.WritePort(SerialBean.java:115)at Frame1.button1_actionPerformed(Frame1.java:66)at Frame1_button1_actionAdapter.actionPerformed(Frame1.java:82)at java.awt.Button.processActionEvent(Button.java:329)at java.awt.Button.processEvent(Button.java:302)at java.awt.Component.dispatchEventImpl(Component.java:2593)at java.awt.Component.dispatchEvent(Component.java:2497)at java.awt.EventQueue.dispatchEvent(EventQueue.java:339)at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:131)at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:98)at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)at java.awt.EventDispatchThread.run(EventDispatchThread.java:85)-----------------------------------------------------------------------------------
I tried to debug it in Frame1.java:66 and SerialBean.java:115 but I can not find any error.
How to deal with it?
Here are the code about package serial
Help me !!!
[ September 02, 2002: Message edited by: Mapraputa Is ]