String Rotation done plus some clean up

Author: rampatra

src/main/java/com/ctci/arraysandstrings/StringRotation.java

@@ -0,0 +1,39 @@
+package com.ctci.arraysandstrings;
+
+/**
+ * Assume you have a method isSubString which checks if one word is a substring of another. Given two
+ * strings, S1 and S2, write code to check if S2 is a rotation of S1 using only one call to isSubString
+ * (e.g., "waterbottle" is a rotation of" erbottlewat").
+ *
+ * @author rampatra
+ * @since 2019-01-22
+ */
+public class StringRotation {
+
+    private static boolean isStringRotation(String s1, String s2) {
+        if (s1.length() != s2.length()) {
+            return false;
+        }
+        s2 = s2 + s2;
+        return isSubString(s1, s2);
+    }
+
+    /**
+     * Given method in question.
+     *
+     * @param s1 first string
+     * @param s2 second string
+     * @return {@code true} if s1 is a substring of s2 or else {@code false}
+     */
+    private static boolean isSubString(String s1, String s2) {
+        return s2.contains(s1);
+    }
+
+    public static void main(String[] args) {
+        System.out.println(isStringRotation("waterbottle", "erbottlewat")); // true
+        System.out.println(isStringRotation("rampatra", "atraramp")); // true
+        System.out.println(isStringRotation("rampatra", "arampata")); // false
+        System.out.println(isStringRotation("rampatra", "arampat")); // false
+        System.out.println(isStringRotation("", "")); // true
+    }
+}

src/main/java/com/rampatra/linkedlists/LRUCache.java

@@ -49,14 +49,14 @@ E get(E item) {
         return itemFromCache;
     }
 
-    void printCache() {
+    private void printCache() {
         Iterator<E> iterator = linkedHashMap.keySet().iterator();
         while (iterator.hasNext()) {
             System.out.print(iterator.next() + ((iterator.hasNext()) ? "," : "\n"));
         }
     }
 
-    public static void main(String a[]) {
+    public static void main(String[] a) {
         LRUCache<Integer> cache = new LRUCache<>(3);
         cache.add(1);
         cache.add(2);

src/main/java/com/rampatra/linkedlists/MaximumSumLinkedList.java

@@ -75,7 +75,7 @@ public static <E extends Comparable<E>> SingleLinkedNode<E> maximumSumLinkedList
         return head;
     }
 
-    public static void main(String a[]) {
+    public static void main(String[] a) {
         SingleLinkedList<Integer> linkedList1 = new SingleLinkedList<>();
         linkedList1.add(00);
         linkedList1.add(11);

src/main/java/com/rampatra/linkedlists/MergeSort.java

@@ -111,7 +111,7 @@ public static <E extends Comparable<E>> SingleLinkedNode<E> mergeTwoSortedLists(
         return head.next;
     }
 
-    public static void main(String a[]) {
+    public static void main(String[] a) {
         SingleLinkedList<Integer> linkedList = new SingleLinkedList<>();
         linkedList.add(21);
         linkedList.add(33);