Static keyword Doubt

[Muneeswaran Balasubramanian]

Hi to all,

i have heard ,if we use static key word for any method or variable ,we have to call the method using the classname like,ClassName.variableName
But in the below program the static method sleep of thread called without class name.How it is possible?

Code:

class Test
{

    public static void main(String argv[])
    {
        Test1 pm1 = new Test1("One");
        pm1.run();
        Test1 pm2 = new Test1("Two");
        pm2.run();

    }
}

class Test1 extends Thread
{

    private String sTname = "";

    Test1(String s)
    {
        sTname = s;

    }

    @Override
    public void run()
    {
        for (int i = 0; i < 2; i++)
        {
            try
            {
                sleep(10000);
            } catch (InterruptedException e)
            {
            }

            yield();
            System.out.println(sTname);
        }

    }
}

Please help me.Thanks in advance.

[Sudhakar Sharma]

Hi,

Static applied to the Class, it doesn't mean we can't access that property using the object of that class.

thanks & regards

[selva nayagam.K]

Hi Muneeswaran Balasubramanian,

Since you extend Thread class all the public methods of thread class becomes the part
of the extended class. As you know to call local method of the class can be just called with their name
we call sleep methods. For more information please see

[Vijay Tidake]

Hi,

Here you are extending the Thread class,So the child class directly inheriting a method from the parent.

If you try to implement the Runnable interface,then you will not be able to do the same.

Thanks

[Thorsten Schneider]

The static methods yield() and sleep() aren't inherited!

But as the Thread class is part of the inheritance tree of your class the compiler will invoke those methods from the Thread class.

[lambadi ganesh]

in java there is a concept called "static import " if you was imported like static import then there is no need of class name to call any function . you can dirlty called any method which is static.

[Dieter Quickfend]

Yes, I do believe lambadi is right. Static methods are not inherited, so a subclass of Thread shouldn't be able to call it from the this reference. This should be an omitted static import.

I'm really really not a fan of static imports.

[Mala Gupta]

The following code will clear all the doubts:

class Parent {
	static String name = "Parent";
	static int age = 50;
}

class Child extends Parent {
	static String name = "Child";
	static String language = "Java";
}

class TestStaticInheritance {
	public static void main (String[] args) {
		// ACCESSING STATIC VARIABLES USING INSTANCE VARIABLES
		Child child = new Child();
		System.out.println (child.name);       	// prints Child
		System.out.println (child.age);			// prints 50
		System.out.println (child.language);	// prints Java
		System.out.println ();

		Parent parent = new Child();
		System.out.println (parent.name);		// prints Parent
		System.out.println (parent.age);		// prints 50
		//System.out.println (parent.language);    WON'T COMPILE!

		// ACCESSING STATIC VARIABLES USING CLASS NAME
		System.out.println ("=========");
		System.out.println (Child.name);       	// prints Child
		System.out.println (Child.age);			// prints 50
		System.out.println (Child.language);	// prints Java
		System.out.println ();

		System.out.println (Parent.name);		// prints Parent
		System.out.println (Parent.age);		// prints 50
		//System.out.println (Parent.language);    WON'T COMPILE!
	}
}

cheers
Mala