Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException

[jeus]

دوستان من وقتی که میخواهم برنامه را run کنم این ارور را میده

 at institute.SQLString.selectspc(SQLString.java:17)

        at institute.TEST.<init>(TEST.java:26)

        at institute.TEST$15.run(TEST.java:333)

        at java.awt.event.InvocationEvent.dispatch(Invocation  Event.java:209)

        at java.awt.EventQueue.dispatchEvent(EventQueue.java:  597)

        at java.awt.EventDispatchThread.pumpOneEventForFilter  s(EventDispatchThread.java:273)

        at java.awt.EventDispatchThread.pumpEventsForFilter(E  ventDispatchThread.java:183)

        at java.awt.EventDispatchThread.pumpEventsForHierarch  y(EventDispatchThread.java:173)

        at java.awt.EventDispatchThread.pumpEvents(EventDispa  tchThread.java:168)

        at java.awt.EventDispatchThread.pumpEvents(EventDispa  tchThread.java:160)

        at java.awt.EventDispatchThread.run(EventDispatchThre  ad.java:121)

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