Hi all

Can any one tell me why I am getting the following exceptions for the file 
I have attached.


Thanks

Sandhya

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at javax.swing.ImageIcon.<init>(ImageIcon.java:138)
        at sim.app.myModelApr01.MyNetworkGUI.setupPortrayals
(MyNetworkGUI.java:66)
        at sim.app.myModelApr01.MyNetworkGUI.start(MyNetworkGUI.java:54)
        at sim.display.Console.startSimulation(Console.java:1248)
        at sim.display.Console.pressPlay(Console.java:2020)
        at sim.display.Console$1.actionPerformed(Console.java:246)
        at javax.swing.AbstractButton.fireActionPerformed
(AbstractButton.java:1995)
        at javax.swing.AbstractButton$Handler.actionPerformed
(AbstractButton.java:2318)
        at javax.swing.DefaultButtonModel.fireActionPerformed
(DefaultButtonModel.java:387)
        at javax.swing.DefaultButtonModel.setPressed
(DefaultButtonModel.java:242)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased
(BasicButtonListener.java:236)
        at java.awt.Component.processMouseEvent(Component.java:6038)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3260)
        at java.awt.Component.processEvent(Component.java:5803)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4410)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.LightweightDispatcher.retargetMouseEvent
(Container.java:4322)
        at java.awt.LightweightDispatcher.processMouseEvent
(Container.java:3986)
        at java.awt.LightweightDispatcher.dispatchEvent
(Container.java:3916)
        at java.awt.Container.dispatchEventImpl(Container.java:2102)
        at java.awt.Window.dispatchEventImpl(Window.java:2429)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters
(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter
(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy
(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents
(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents
(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)
BUILD SUCCESSFUL (total time: 7 seconds)