pls i need help!I am writing a code to turn on and turn off a light bulb between a client side and a server side using sockets in java.The thing communicates but i am having problem puttin it on gui radio buttons .I called the method to sendMesage from the actionlistener in radio button but it doesnt send any thing instead it complains.

public void actionPerformed(ActionEvent e)    
      {
        Object source = e.getSource();
       
		String message = "bedRoomLon";
	 if(source==radioOn || source==radioOff)
         {
         
        if(source== radioOn)
	{
                        
	
              client.sendMessage(message); 
	label1.setIcon(createImageIcon("images/" + e.getActionCommand()+ ".jpg"));
                           radioOn.setSelected(true);
			         (message); 
	}
      else if(source== radioOff)
                          {
		                label1.setIcon(createImageIcon("images/" + e.getActionCommand()+ ".jpg"));
                           }            
 


}
   
		
                          

public void sendMessage(String msg)
		{
	try{
 // out = new ObjectOutputStream(requestSocket.getOutputStream());
			//out.flush();
	
			out.writeObject(msg);
			out.flush();
			System.out.println("client>" + msg);

		}
		catch(IOException ioException){
			ioException.printStackTrace();
		}
		
					
//The error given is below 


Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at ClientPanel.actionPerformed(ClientPanel.java:373)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1849)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2169)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
        at javax.swing.JToggleButton$ToggleButtonModel.setPressed(JToggleButton.java:269)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
        at java.awt.Component.processMouseEvent(Component.java:5517)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3135)
        at java.awt.Component.processEvent(Component.java:5282)
        at java.awt.Container.processEvent(Container.java:1966)
        at java.awt.Component.dispatchEventImpl(Component.java:3984)
        at java.awt.Container.dispatchEventImpl(Container.java:2024)
        at java.awt.Component.dispatchEvent(Component.java:3819)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3892)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
        at java.awt.Container.dispatchEventImpl(Container.java:2010)
        at java.awt.Window.dispatchEventImpl(Window.java:1791)
        at java.awt.Component.dispatchEvent(Component.java:3819)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at ClientPanel.ExitServe(ClientPanel.java:496)
        at ClientPanel.actionPerformed(ClientPanel.java:387)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1849)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2169)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
        at javax.swing.JToggleButton$ToggleButtonModel.setPressed(JToggleButton.java:269)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
        at java.awt.Component.processMouseEvent(Component.java:5517)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3135)
        at java.awt.Component.processEvent(Component.java:5282)
        at java.awt.Container.processEvent(Container.java:1966)
        at java.awt.Component.dispatchEventImpl(Component.java:3984)
        at java.awt.Container.dispatchEventImpl(Container.java:2024)
        at java.awt.Component.dispatchEvent(Component.java:3819)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3892)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
        at java.awt.Container.dispatchEventImpl(Container.java:2010)
        at java.awt.Window.dispatchEventImpl(Window.java:1791)
        at java.awt.Component.dispatchEvent(Component.java:3819)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at ClientPanel.actionPerformed(ClientPanel.java:373)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1849)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2169)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
        at javax.swing.JToggleButton$ToggleButtonModel.setPressed(JToggleButton.java:269)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
        at java.awt.Component.processMouseEvent(Component.java:5517)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3135)
        at java.awt.Component.processEvent(Component.java:5282)
        at java.awt.Container.processEvent(Container.java:1966)
        at java.awt.Component.dispatchEventImpl(Component.java:3984)
        at java.awt.Container.dispatchEventImpl(Container.java:2024)
        at java.awt.Component.dispatchEvent(Component.java:3819)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3892)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
        at java.awt.Container.dispatchEventImpl(Container.java:2010)
        at java.awt.Window.dispatchEventImpl(Window.java:1791)
        at java.awt.Component.dispatchEvent(Component.java:3819)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)

The exception tells you you have an unitialised variable on line 373 of ClientPanel (in method actionPerformed). Look at that line and work out which variable it is. If you're not sure, print them all to see which is null.

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