Adding 3 way quick sort

clients/src/main/java/com/hithomelabs/clients/module7/ThreeWayQuickSortClient.java

@@ -0,0 +1,23 @@
+package com.hithomelabs.clients.module7;
+
+import com.hithomelabs.princeton1.common.Apple;
+import com.hithomelabs.princeton1.module7.Quick;
+import com.hithomelabs.princeton1.module7.ThreeWayQuick;
+
+import java.util.Random;
+
+public class ThreeWayQuickSortClient {
+
+    public static void main(String[] args) {
+        int size = 100;
+        Apple[] apples = new Apple[size];
+        ThreeWayQuick<Apple> quick = new ThreeWayQuick<>();
+
+        for (int i = 0; i < apples.length; i++) {
+            apples[i] = new Apple(new Random().nextInt(10));
+        }
+        quick.sort(apples);
+        for (int i = 0; i < apples.length; i++)
+            System.out.println(apples[i]);
+    }
+}

module7/src/main/java/com/hithomelabs/princeton1/module7/ThreeWayQuick.java

@@ -0,0 +1,41 @@
+package com.hithomelabs.princeton1.module7;
+
+import com.hithomelabs.princeton1.module5.AbstractCustomSorts;
+
+public class ThreeWayQuick<E> extends AbstractCustomSorts<E> {
+    @Override
+    public void sort(E[] arr) {
+        coreSortingLogic(arr);
+    }
+
+    private void coreSortingLogic(E[] arr) {
+        int N = arr.length;
+        threeWaySort(arr, 0, N - 1);
+    }
+
+    private void threeWaySort(E[] arr, int lo, int hi) {
+
+        if(hi <= lo)
+            return;
+        int k = hi;
+        int i = lo + 1;
+        int j = lo;
+
+        while (true) {
+            if (((Comparable<E>) arr[i]).compareTo(arr[j]) < 0) {
+                exch(arr, i, j++);
+                i++;
+            } else if (((Comparable<E>) arr[i]).compareTo(arr[j]) > 0)
+                exch(arr, i, k--);
+            else {
+                i++;
+            }
+
+            if (k < i)
+                break;
+        }
+        threeWaySort(arr, lo, j - 1);
+        threeWaySort(arr, k + 1, hi);
+    }
+
+}