About Multithreading in java

[Rajesh raju]

Is Runnable interface is better or Extending thread is better.Please clarify in detail why it is better.

[Balasubramanian Chandrasekaran]

Originally posted by Rajesh raju:
Is Runnable interface is better or Extending thread is better.Please clarify in detail why it is better.

Thread class also implements Runnable interface only.
If you see the source code of Thread Class.You can see this line

public class Thread implements Runnable

So i think both the things has the same effect.

[Rob Spoor]

The big difference is reusability.

A thread can be run only once; after it has finished, calling start again will result in an exception. You can reuse a Runnable in multiple threads though, even at the same time.

Of course this still requires creating a thread for each time you need to run it, so in the end the number of objects created will be more or less the same.

[Raghavan Muthu]

Adding on top of what Rob Prime told, a simple way to get another advantage is by implementing an interface my class is free to extend some other business class

[William Brogden]

I have extended Thread when I wanted to make use of the ThreadGroup as a simple way to track the status of working Threads.

Bill

[sarvesh meens]

A thread should be extended only when its behaviour has to be extended/modified(which is very rare).
The general requirement is to execute a task/group-of-statements on a seperate thread. Implementing Runnable is the right solution for this requirment.

Refer to Thread FAQ for more details.