Threads??

[srikanth reddy]

 class A extends Thread {
  private Object obj;
  public A(Object obj) {this.obj = obj;}
  public void run() {
    try {
      synchronized (obj) {obj.wait();}//2
    } catch (InterruptedException ie) {}
    System.out.print(Thread.currentThread().getName());
}}
class B {
  private void m1() {
    for (int i = 0; i < 10; i++) {
      A t1 = new A(this);//1
      t1.setName(String.valueOf(i));
      t1.setDaemon(true);
      t1.start();
    }
    synchronized (this) {notifyAll();}
  }
  public static void main(String[] args) {
    new B().m1();
}}
 

frnds
this code is not compiling giving error as there is no constructor in the class A which accepts B ..
my doubt is there is an Object type and every class extends Object so why there is a compilation error ...this is from dan question and the answer given is
b.some or all of the numbers 0 through 9 could be printed
c.There is no guarantee that anything will be printed

and one more doubt is at line 2.each thread has their own object and acquire lock on it ??since it is not static !!!

please clarify....

[Barry Gaunt]

Compiles fine for me using Java 5.0.

[Barry Gaunt]

"each thread has their own object and acquire lock on it ?"

No, there are many threads but only one object is being synchronized upon - the instance of class B.

[patrick J. d'cousta]

According to me the answer for this question is
that we dont know what will be output.Since all are daemon threads
it may be possible that main thread exits as soon as all waiting threads are notified.Am i correct?

[srikanth reddy]

barry iam using JDK 1.4...iam getting compiler error....

[Barry Gaunt]

Compiles and runs under Java 1.4.2_2 too.