source file name:  ActionPoints.java

import java.io.*;

class Points

{

int x1,x2,y1,y2;

public Points(int p,int q,int r,int s)

{

x1=p;y1=q;x2=r;y2=s;

}

public void disppoints()

{

System.out.println("x1: "+x1+" y1= "+y1);

System.out.println("x2: "+x2+" y2= "+y2);

}

public void length()

{

double len;

len=Math.sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1));

System.out.println("length of segment QP is = "+len);

}

public void slope()

{

double len;

len=(y2-y1)/(x2-x1);

System.out.println("slope of segment QP is ="+len);

}

}

class ActionPoints

{

public static void main(String as[])

{ 

Points p1=new Points(10,10,11,11);

p1.disppoints();

p1.length();

p1.slope();

Points p2=new Points(10,-5,16,10);

p2.disppoints();

p2.length();

p2.slope();

}

}

output:

D:\JavaPrograms\Constructors>javac ActionPoints.java

D:\JavaPrograms\Constructors>java ActionPoints
x1: 10 y1= 10
x2: 11 y2= 11
length of segment QP is = 1.4142135623730951
slope of segment QP is =1.0
x1: 10 y1= -5
x2: 16 y2= 10
length of segment QP is = 16.15549442140351
slope of segment QP is =2.0