this keyword in java

1this() : used for calling the constructor . 
2  we can only use it in the constructor
3this. : used for calling the instance variables 
4we can use in any object instances
5

1// java program using ‘this’ keyword
2class Demo
3{
4   int m;
5   int n;
6   public void setValue(int m, int n)
7   {
8      // java this keyword
9      this.m = m;
10      this.n = n;
11   }
12   public void showValue()
13   {
14      System.out.println("Value m = " + m);
15      System.out.println("Value n = " + n);
16   }
17}
18public class ThisExample
19{
20   public static void main(String[] args)
21   {
22      Demo obj = new Demo();
23      obj.setValue(5,6);
24      obj.showValue();
25   }
26}

1class Other{
2    public double num;
3    public Other(int num){
4        this.num = num;
5        System.out.println(num);
6      	//print 5 to the console
7    }
8}
9
10class scratch{
11    public static void main(String[] args) {
12        Other method = new Other(5);
13        System.out.println(method.num);
14      	//prints 5.0 to the console
15    }
16}

1// this keyword in java example
2import java.util.*;
3class Demo
4{
5   // instance variable
6   int m;
7   int n;
8   public void setValue(int m, int n)
9   {
10      m = m;
11      n = n;
12   }
13   public void showValue()
14   {
15      System.out.println("Value m = " + m);
16      System.out.println("Value n = " + n);
17   }
18}
19public class ThisKeywordDemo
20{
21   public static void main(String[] args)
22   {
23      Demo obj = new Demo();
24      obj.setValue(5, 6);
25      obj.showValue();
26   }
27}