[問題]關於Thread出現NullPointerException的問題
小妹有個問題需請求各位高手幫忙:
最近在接觸JAVA Thread這部分,練習了一個使用Thread取得亂數的小程式,
以下為程式部分:
class MyThread extends Thread{
MyThread(int c){ start();
...}
public void run(){
lotto.getChose();
}
}
class BigLottos{){
public void getChose(){
選取亂數的過程...
try{
Thread.sleep(2000);
}
catch(InterruptedException e){
}
}
}
public class ThreadLotto {
public static void main(String[] args){
MyThread ob1=new MyThread(50);
System.out.println("所選取的號碼如下: ");
}
}
編譯後產生以下例外訊息,似乎是取得的執行緒是空的~"~
不知道問題出在哪裡,為什麼會讀不到所產生的Thread?
Exception in thread "Thread-0" java.lang.NullPointerException
at test1.MyThread.run(ThreadLotto.java:23)
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