Thread --> run() method

[Subhro Chowdhury]

A static variable can't be accessed from a non-static method. But we can access a static variable inside run() method.

 package com.pspl.thread;
 
public class TestClass extends Thread
{
   private static int threadcounter = 0;
   public void run()
   {
threadcounter++;
System.out.println(threadcounter);
   }
   public static void main(String[] args) throws Exception
   {
for(int i=0; i<10; i++)
{
   synchronized(TestClass.class)
   {
new TestClass().start();
   }
}
   }
   
}
 
   

This code compile and run successfully. How come we are accessing the threadcounter inside run() ?

[Joanne Neal]

Originally posted by Subhro Chowdhury:
A static variable can't be accessed from a non-static method.

Yes it can. Non-static variables can't be accessed from a static method.

[Leandro Melo]

Hi.

This is easy to understand. A static member (method or variable) doesn't belong to any instance of a class, it belongs to the class itself. Therefore, you can't access, for example, a non-static member from inside a static method, because there's no direct relationship that tells from which instance of the class the non-static member refers to. However, the other way around is perfectly acceptable, because a non-static method knows the class it belongs to, and then can access static members of this class.

[Subhro Chowdhury]

Got it. Thanks for the explanation.