import java.util.Collection;
import java.util.Collections;
import java.util.Set;
import java.util.TreeSet;
class MyThread implements Runnable {
Thread t;
Collection col;
MyThread(Collection c) {
col = c;
t = new Thread(this, "MyThread");
t.start();
}
public void run() {
try {
Thread.sleep(100);
col.add("D");
synchronized (col) {
for (String str : col) {
System.out.println("MyThread: " + str);
Thread.sleep(50);
}
}
} catch (Exception exc) {
exc.printStackTrace();
}
}
}
public class Main {
public static void main(String args[]) throws Exception {
Set tsStr = new TreeSet();
Collection syncCol = Collections.synchronizedCollection(tsStr);
syncCol.add("A");
syncCol.add("B");
syncCol.add("C");
new MyThread(syncCol);
synchronized (syncCol) {
for (String str : syncCol) {
System.out.println("Main thread: " + str);
Thread.sleep(500);
}
}
}
}