From 86aaeed8e1aa382e41d1a5df817bb993176ff744 Mon Sep 17 00:00:00 2001
From: myluckagain <myluckagain@gmail.com>
Date: Mon, 3 Sep 2018 23:34:21 +0500
Subject: [PATCH] BAEL-2155 (#5149)

---
 .../DistanceBetweenPointsService.java         | 38 +++++++++++++
 .../DistanceBetweenPointsServiceUnitTest.java | 54 +++++++++++++++++++
 2 files changed, 92 insertions(+)
 create mode 100644 algorithms/src/main/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsService.java
 create mode 100644 algorithms/src/test/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsServiceUnitTest.java

diff --git a/algorithms/src/main/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsService.java b/algorithms/src/main/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsService.java
new file mode 100644
index 0000000000..0c8eb86a38
--- /dev/null
+++ b/algorithms/src/main/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsService.java
@@ -0,0 +1,38 @@
+package com.baeldung.algorithms.distancebetweenpoints;
+
+import java.awt.geom.Point2D;
+
+public class DistanceBetweenPointsService {
+
+    public double calculateDistanceBetweenPoints(
+        double x1, 
+        double y1, 
+        double x2, 
+        double y2) {
+        
+        return Math.sqrt((y2 - y1) * (y2 - y1) + (x2 - x1) * (x2 - x1));
+    }
+
+    public double calculateDistanceBetweenPointsWithHypot(
+        double x1, 
+        double y1, 
+        double x2, 
+        double y2) {
+        
+        double ac = Math.abs(y2 - y1);
+        double cb = Math.abs(x2 - x1);
+        
+        return Math.hypot(ac, cb);
+    }
+
+    public double calculateDistanceBetweenPointsWithPoint2D( 
+        double x1, 
+        double y1, 
+        double x2, 
+        double y2) {
+        
+        return Point2D.distance(x1, y1, x2, y2);
+
+    }
+
+}
diff --git a/algorithms/src/test/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsServiceUnitTest.java b/algorithms/src/test/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsServiceUnitTest.java
new file mode 100644
index 0000000000..785afdbb2b
--- /dev/null
+++ b/algorithms/src/test/java/com/baeldung/algorithms/distancebetweenpoints/DistanceBetweenPointsServiceUnitTest.java
@@ -0,0 +1,54 @@
+package com.baeldung.algorithms.distancebetweenpoints;
+
+import org.junit.Test;
+
+import com.baeldung.algorithms.distancebetweenpoints.DistanceBetweenPointsService;
+
+import static org.junit.Assert.assertEquals;
+
+public class DistanceBetweenPointsServiceUnitTest {
+
+    private DistanceBetweenPointsService service = new DistanceBetweenPointsService();
+
+    @Test
+    public void givenTwoPoints_whenCalculateDistanceByFormula_thenCorrect() {
+
+        double x1 = 3;
+        double y1 = 4;
+        double x2 = 7;
+        double y2 = 1;
+
+        double distance = service.calculateDistanceBetweenPoints(x1, y1, x2, y2);
+
+        assertEquals(distance, 5, 0.001);
+
+    }
+
+    @Test
+    public void givenTwoPoints_whenCalculateDistanceWithHypot_thenCorrect() {
+
+        double x1 = 3;
+        double y1 = 4;
+        double x2 = 7;
+        double y2 = 1;
+
+        double distance = service.calculateDistanceBetweenPointsWithHypot(x1, y1, x2, y2);
+
+        assertEquals(distance, 5, 0.001);
+
+    }
+
+    @Test
+    public void givenTwoPoints_whenCalculateDistanceWithPoint2D_thenCorrect() {
+
+        double x1 = 3;
+        double y1 = 4;
+        double x2 = 7;
+        double y2 = 1;
+
+        double distance = service.calculateDistanceBetweenPointsWithPoint2D(x1, y1, x2, y2);
+
+        assertEquals(distance, 5, 0.001);
+
+    }
+}