lỗi gì vậy ????

java.lang.NullPointerException
at com.goldhuman.account.storage.getUseCashNow(Unknow n Source)
at protocol.GAuthServer$1.run(Unknown Source)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
java.lang.NullPointerException
at com.goldhuman.account.storage.getUseCashNow(Unknow n Source)
at protocol.GAuthServer$1.run(Unknown Source)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
java.lang.NullPointerException
at com.goldhuman.account.storage.getUseCashNow(Unknow n Source)
at protocol.GAuthServer$1.run(Unknown Source)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
java.lang.NullPointerException
at com.goldhuman.account.storage.getUseCashNow(Unknow n Source)
at protocol.GAuthServer$1.run(Unknown Source)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)