Threads confusing

[Anantha Krishna]

Hi all,
When I try to run the code using t.start() the output is about both main thread and the child thread. But when I try to run the code with t.run() then the out put is just about the child thread.
Can any one tell the reason why is this behaviour.What is the difference between calling t.start() or calling t.run() directly.
class counter implements Runnable
{
private int currentvalue;
private Thread t;
counter(String threadname)
{
currentvalue=0;
t=new Thread(this,threadname);
System.out.println(t);
t.run();
}//this is for the constructor
public void run()
{
try
{
while(currentvalue<5)
{
System.out.println("The thread's name is"+t.getName()+":"+(currentvalue++));
t.sleep(500);
}
}catch(InterruptedException e)
{
System.out.println("Thread is interrupted");
}
System.out.println("The child thread exitted");
}
public int getValue()
{
return currentvalue;
}
}//this is for the counter class

public class client
{
public static void main(String [] args)
{
counter c=new counter("Child");
try
{
int val;
do
{
val=c.getValue();
System.out.println("The main thread's value is"+val);
Thread.sleep(1000);
}while(val<5);
}catch(InterruptedException e)
{
System.out.println("Main thread interrupted");
}
System.out.println("Main exitted");
}//this is for the main method
}//this is for the class client
THanks & regards
Ananth

[William Brogden]

Thats simple.
t.start() - starts the Thread named t which will execute the run method it is attached to. Note that you can not tell which of the two running Threads will execute next since t inherits the priority of the Thread that created it.
t.run() - the current Thread (which is executing a run method somewhere) now executes the run method attached to Thread t. Thread t remains in a non-running state.
Bill

[karan roy]

whenever we call the t.start() fn,after this line ,the compiler goes back to the method where the constructor was called from
and therefore the main thread starts executing.
and after the main thread,the child thread starts executing(output varies depending on the o.s).
if u call directly the run method only the compiler will move onto that method and start reding it w/out going to the main thread .