explanation needed

[krish bajaj]

what is the concept of class specific locks
help by giving any example

thanks

[Naseem Khan]

When a thread accesses a static synchronized method of a class, then it acquires the class lock i.e., Test.class lock instead of Test's instance lock.

It will be better understood by this code....

    
class Test extends Thread{
public Test(String name){
super(name);
}
public void run(){
meth();
}
public static synchronized void meth(){
while(true){
System.out.println(Thread.currentThread().getName());
}
}
public static void main(String[] args){
Test t=new Test("child");
t.start();
synchronized(Test.class){

while(true){
System.out.println(Thread.currentThread().getName());
}

}
}
}

Here you will get only one output. either main or child.


Naseem

[S Thiyanesh]

class specific locks can be acquired by
1.synchronizing on static methods.
2.synchronizing on the static objects defined in the class.
3.Locking on external objects like System.out
4.Locking on Singleton Objects.

[krish bajaj]

thanks Nassem