processclasslocktest.java

来自「基于LWVCL开发的库」· Java 代码 · 共 78 行

/**
 * a test to ensure we do upcalls to static initializers properly.
 *
 * @author Godmar Back <[e-mail]>
 */
class LockBase {
    static {
	try {
	    Thread.sleep(5000);
	} catch (Exception e) {
	    System.out.println(e);
	}
    }
}

class Sub extends LockBase {
}

public class ProcessClassLockTest
{
    public static void main(String av[]) throws Exception {
	// a watchdog thread that kills us off after 2.5 sec
	new Thread() {
	    public void run() {
		try {
		    Thread.sleep(10000);
		    System.out.println("sorry, you timed out");
		    System.exit(-1);
		} catch (Exception e) {
		    System.out.println(e);
		}
	    }
	}.start();

	// a thread that will load Sub and LockBase
	new Thread() {
	    public void run() {
		try {
		    Class.forName("Sub");
		} catch (Throwable t) {
		    System.out.println(t);
		}
	    }
	}.start();

	// get thread 2 going
	Thread.sleep(1000);

	/* this thread should be unaffected by the fact that thread 2
	 * sleeps in the static initializer of LockBase
	 */
	Thread th;
	th = new Thread() {
	    public void run() {
		try {
		    Class.forName("this_class_does_not_exist");
		} catch (Throwable t) {
		    System.out.println(t.getClass().getName()+": "+t.getMessage().substring(0, 25));
		}
		System.exit(0);
	    }
	};
	th.start();
	try
	{
	    th.join();
	}
	catch (InterruptedException ie)
	{
	    System.out.println("interrupted");
	}
    }
}

/* Expected Output:
java.lang.ClassNotFoundException: this_class_does_not_exist
*/