2 methods to calculate distance between two points in java with code example. 1- Using formula. 2- Using a Point class objects.

## Distance between two points using formula

We know that the distance between two points (x1,y1) and (x2,y2) on a flat surface is as below. That we’ll use in the java program to find distance.

```
____________________
/ 2 2
\/ (y2-y1) + (x2-x1)
```

**Code Example:**

This is very simple java program to demonstrate how we can calculate the distance between two co-ordinates / points using formula.

```
/*--------------------------------------------------------
* Simple example to get distance between two points
* (x1,y1) and (x2,y2)
*/
public class Sample {
public static void main(String[] args) {
// point 1
double x1 = 1;
double y1 = 1;
// point 2
double x2 = 5;
double y2 = 5;
// Calculate distance between two points
double distance = Math.sqrt((x2 - x1) * (x2 - x1) + (y2 - y1)
* (y2 - y1));
System.out.println("Distance between two points :" + distance);
}
}
```

## Distance between two points using Point Class

This program has a class Point with fields X and Y. We will create two objects of it representing two points.

It contains a method “double getDistance(Point p)” that returns distance between two points.

**Code Example:**

```
/*---------------------------------------------------------
* Example to calculate distance between two points objects.
*/
class Point {
private double x;
private double y;
Point(double x, double y) {
this.x = x;
this.y = y;
}
public double getX() {
return x;
}
public double getY() {
return y;
}
// This method accept a point object
// and calculate distance with current object.
// "this" keyword refer current object.
public double getDistance(Point p) {
return Math.sqrt((this.getX() - p.getX()) * (this.getX() - p.getX())
+ (this.getY() - p.getY()) * (this.getY() - p.getY()));
}
}
public class Sample {
public static void main(String[] args) {
Point px = new Point(1, 1);
Point py = new Point(5, 5);
double distance = px.getDistance(py);
System.out.println(distance);
}
}
```