ダイナミックスプライト - スレッドの例外 "AWT-EventQueueの-0" のjava.lang.NullPointerException

Question

GameCanvas

AppleEnity - http://pastebin.com/ZVyL5fRm

Enity - （2つの以上のリンクを投稿カントbin.com/r4cqtr8Bを貼り付けまだ）

私は新しい、動的スプライトを私のシーンに追加することに問題があります。 E（ランダムにリンゴを起動する必要がありで）を押すと、私は、このエラーを与える：

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException 
at start.GameCanvas.dodaj(GameCanvas.java:65) 
at start.GameCanvas.keyPressed(GameCanvas.java:149) 
at java.awt.Component.processKeyEvent(Unknown Source) 
at java.awt.Component.processEvent(Unknown Source) 
at java.awt.Component.dispatchEventImpl(Unknown Source) 
at java.awt.Component.dispatchEvent(Unknown Source) 
at java.awt.KeyboardFocusManager.redispatchEvent(Unknown Source) 
at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(Unknown Source) 
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(Unknown Source) 
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(Unknown Source) 
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(Unknown Source) 
at java.awt.Component.dispatchEventImpl(Unknown Source) 
at java.awt.Component.dispatchEvent(Unknown Source) 
at java.awt.EventQueue.dispatchEventImpl(Unknown Source) 
at java.awt.EventQueue.access$000(Unknown Source) 
at java.awt.EventQueue$3.run(Unknown Source) 
at java.awt.EventQueue$3.run(Unknown Source) 
at java.security.AccessController.doPrivileged(Native Method) 
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) 
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) 
at java.awt.EventQueue$4.run(Unknown Source) 
at java.awt.EventQueue$4.run(Unknown Source) 
at java.security.AccessController.doPrivileged(Native Method) 
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) 
at java.awt.EventQueue.dispatchEvent(Unknown Source) 
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) 
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) 
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) 
at java.awt.EventDispatchThread.pumpEvents(Unknown Source) 
at java.awt.EventDispatchThread.pumpEvents(Unknown Source) 
at java.awt.EventDispatchThread.run(Unknown Source) 

Answer 1

問題は、この行で明らかである：

jablka.add(new AppleEnity("resources/apple.png", random.nextInt(400), random.nextInt(400))); 

...しかし、それはおよそjablka変数ではないのですが、これと表現：

random.nextInt(400) 

あなたがrandom変数を初期化することはありません：

private Random random; 

はと上の行に置き換えます

private final Random random = new Random(); 

をそして、あなたは大丈夫です。または、MathオブジェクトまたはRandomUtilsオブジェクトを使用してください。