Thread: How to capture signature using Canvas and save in png format?

it doesnt have error message. i can compile it, just it has red line below the text. and when i pressed save button it eventdispatchthread. java and show this

if (theQueue.peekEvent() != null ||
!SunToolkit.isPostEventQueueEmpty()) {
theQueue.initDispatchThread();
}
AWTAutoShutdown.getInstance().notifyThreadFree(thi s);
}
}
}

void pumpEvents(Conditional cond) {
pumpEvents(ANY_EVENT, cond);
}

void pumpEventsForHierarchy(Conditional cond, Component modalComponent) {
pumpEventsForHierarchy(ANY_EVENT, cond, modalComponent);
}

yeah, becuse i dont understand java programming, that why i need your help