test32.java

来自「SCJP认证考试资料」· Java 代码 · 共 21 行

public class Test32 {
    static private int alt;
    static public synchronized void up() {
	++alt;
    }
    static  public void down() {
	--alt;
    }
    public static synchronized void jump() {
	int a = alt;
	up();
	down();
	System.out.println(a==alt);
	assert(a==alt);
    }
    public static void main(String[] args) {
	jump();
    }
}