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"AWT-EventQue-0" java.lang.NullPointerException is kicking my butt  RSS feed

 
Selig Amsel
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So, I am making a rudimentary Minesweeper knockoff for a homework assignment. I am trying to call some of the methods in my Minesweeper class from my MineButton class. However, I get a NullPointerException. There are about a thousand questions about this particular issue, but I can't find a solution to my problem from those. Apparently something is null, but I've initialized everything properly (obviously not, though). I really need some help on figuring this out. The two classes that matter are shown below along with the stack trace.






Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at MineButton.evaluateLClick(MineButton.java:34)
at MineButton$MouseHandler.mouseClicked(MineButton.java:46)
at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:270)
at java.awt.Component.processMouseEvent(Component.java:6528)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6290)
at java.awt.Container.processEvent(Container.java:2234)
at java.awt.Component.dispatchEventImpl(Component.java:4881)
at java.awt.Container.dispatchEventImpl(Container.java:2292)
at java.awt.Component.dispatchEvent(Component.java:4703)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4898)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4542)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4462)
at java.awt.Container.dispatchEventImpl(Container.java:2278)
at java.awt.Window.dispatchEventImpl(Window.java:2739)
at java.awt.Component.dispatchEvent(Component.java:4703)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:746)
at java.awt.EventQueue.access$400(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:697)
at java.awt.EventQueue$3.run(EventQueue.java:691)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.
java:75)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.
java:86)
at java.awt.EventQueue$4.run(EventQueue.java:719)
at java.awt.EventQueue$4.run(EventQueue.java:717)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.
java:75)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:716)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.ja
va:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:
116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.ja
va:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

The error is on line 34 of my MineButton class and has something to do with play, but I don't know how to fix it.
Thanks for any help in advance.
 
Campbell Ritchie
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Welcome to the Ranch

Please go through the stack trace again. Line 34 is empty, so it can't be there that you are suffering the Exception.
 
Omar Rashwan
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In the MineButton class constructor you initialized the Minesweeper --- play -- in the Args to so this will call the non-arg constructor in
Minesweeper class --- which did not initialize the it the Array you guess ---
after that you assigned the new object to the MineButton instance variable play...
Look at this code

replace it with this code
 
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