Meaning Of this() in Java

The keyword this in #Java refers to the current class instance i.e object. It can be used in multiple ways,
e.g
class Square{
Square(int height, int width)
{
this.height = height;
this.width = width;
}
}
Here this keyword makes sure the parameters
belongs to object and not parameters passed through
constructor Square().
Now what is
this():
this keyword here basically points to the constructor
of the class.
It can be used by one constructor to explicitly invoke
another constructor in the same class.
e.g
class Square
{
int height;
int width;
Square()
{
this(0,0);
}
Square(int side)
{
this(side, side);
}
Square(int height, int width)
{
this.height = height;
this.width = width;
}
}
So here, if we pass no arguments to constructor, 0 is
taken as both arguments and if only one argument is
passed then same value is used for both height and
width.

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