QUESTION 47

QUESTION 47 
Given: 
 
1. public class TestSeven extends Thread { 
2.     private static int x; 
3.     public synchronized void doThings() { 
4.         int current = x; 
5.         current++; 
6.         x = current; 
7.     } 
8.     public void run() { 
9.         doThings(); 
10.     } 
11. } 
 
Which statement is true? 
 
A. Compilation fails. 
B. An exception is thrown at runtime. 
C. Synchronizing the run() method would make the class thread-safe. 
D. The data in variable x are protected from concurrent access problems. 
E. Declaring the doThings() method as static would make the class thread-safe. 
F. Wrapping the statements within doThings() in a synchronized(new Object()) { } block would make the class thread-safe. 
Solution : E