Runnable Interface
Package: java.lang
The Runnable
interface describes a class whose instances can be run as a thread. The interface itself is very simple, describing only one method (run
) that is called automatically by Java when the thread is started.
The Runnable
interface is usually used in conjunction with the Thread
class. For more information, see Thread Class.
Methods
Method |
Explanation |
|
Called when the thread is started. Place the code that you want the thread to execute inside this method. |
To use the Runnable
interface to create and start a thread, you have to do the following:
1. Create a class that implements Runnable
.
2. Provide a run
method in the Runnable
class.
3. Create an instance of the Thread
class and pass your Runnable
object to its constructor as a parameter.
A Thread
object is created that can run your Runnable
class.
4. Call the Thread
object’s start
method.
The run
method of your Runnable
object is called and executes in a separate thread.
Here’s an example of a class that implements Runnable
:
public class RunnableClass implements Runnable1
{
public void run()
{
// code to execute when thread is run
// goes here
}
}
Here’s an example that instantiates a RunnableClass
object, and then creates a Thread
object to run the RunnableClass
object:
RunnableClass rc = new RunnableClass();
Thread t = new Thread(rc);
t.start();