Can someone explain to me in detail the use of 'this'?

Question

I don\'t really understand the use of \'this\' in Java. If someone could help me clarify I would really appreciate it.

On this website it says: http://docs.oracle.com/ja

Answer 1

"this" is a reference to the current object you are using. You use it when you have a name clash between a field and a parameter. Parameter takes precedence over fields.

No clash, no need for this:

public Point(int a, int b) {
    x = a;
    y = b;
}

But this will work, too:

public Point(int a, int b) {
    this.x = a;
    this.y = b;
}

Name clash, need to use "this":

public Point(int x, int y) {
    this.x = x;
    this.y = y;
}

If you did only

public Point(int x, int y) {
    x = x;
    y = y;
}

then you would just assign parameters with its own value, which effectively does nothing.

There are more usages of keyword "this".