單項選擇題
public class X implements Runnable (
private int x;
private int y;
public static void main(String args) (
X that = new X();
(new Thread(that)) . start( );
(new Thread(that)) . start( );
)
public synchronized void run( ) (
for (;;) (
x++;
y++;
System.out.printIn(“x = “ + x + “, y = “ + y);
)
)
)
What is the result?()
A. An error at line 11 causes compilation to fail.
B. Errors at lines 7 and 8 cause compilation to fail.
C. The program prints pairs of values for x and y that might not always be the same on the same line (for example, “x=2, y=1”)
D. The program prints pairs of values for x and y that are always the same on the same line (forexample, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=1, y=1”)
E. The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=2s, y=2”)