how to call one constructor from the other constructor in java code example

Example 1: java call another constructor

public class Foo {
    private int x;

    public Foo() {
        this(1);
    }

    public Foo(int x) {
        this.x = x;
    }
}

Example 2: calling this in constructor java

In Java another constructor of the same class can be called from a
  constructor via this().
 Note however that this has to be on the first line.