SCJP題庫第224題
Given:
1. public class Threads4{
2. public static void main(String[] args){
3. new Threads4.go();
4. }
5. public void go(){
6. Runnable r = new Runnable(){
7. public void run(){
8. System.out.print("foo");
9. }
10. };
11. Thread t = new Thread(r);
12. t.start();
13. t.start();
14. }
15.}
What is the result?
A. Compilation fails.
B. An exception is thrown at runtime.
C. The code executes normally and prints "foo";
D. The code executes normally, but nothing is printed.
Ans: B
解說:一個執行緒只能啟動一次 (t.start()只能下一次)，執行緒是物件，物件相關的動作發生問題是在執行時期產生例外，而不是編譯的錯誤。
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