This keyword in java

Sometimes a method will need to refer to the object that invoked it. To allow this, Java

defines the this keyword. this can be used inside any method to refer to the current object.

// A redundant use of this.

Box(double w, double h, double d) //constructor

{

this.width = w;

this.height = h;

this.depth = d;

}

Box ob1 = new Box(2,3,4);

// this refer to object ob1 here

Box ob2 = new Box(5,6,7);

//this refer to object ob2 here

void display( ) // method

{

System.out.println(this.width+” “+this.height+” “+this.depth);

}

ob1.display();

// this refer to object ob1 here.

It is illegal in Java to declare two local variables with the same name inside the same or

enclosing scopes. When a local variable has the same name as an instance variable, the local

variable hides the instance variable.

Because ‘this’ refer directly to the object, we can use it to resolve any name space collisions

that might occur between instance variables and local variables.

// Use this to resolve name-space collisions.

Box(double width, double height, double depth)

{

this.width = width;

this.height = height;

this.depth = depth;

}