Camel Case

ardallie · ardallie · commit 731b9122987f · 2021-08-11T23:11:27.000+01:00
diff --git a/src/easy/CamelCase.java b/src/easy/CamelCase.java
@@ -0,0 +1,65 @@
+package easy;
+
+/**
+ * Have the function CamelCase(str) take the str parameter being passed
+ * and return it in proper camel case format where the first letter
+ * of each word is capitalized (excluding the first letter).
+ * ---
+ * The string will only contain letters and some combination of delimiter
+ * punctuation characters separating each word.
+ * For example: if str is "BOB loves-coding" then your program
+ * should return the string bobLovesCoding.
+ */
+public class CamelCase {
+
+  /**
+   * A helper function which removes non-alphabetic characters,
+   * converts to a lower case and trims the string.
+   *
+   * @param str input string
+   * @return a string with non-alphabetic characters removed
+   */
+  private static String[] splitWords(String str) {
+    return str
+        .toLowerCase()
+        .replaceAll("([^a-z])", " ")
+        .replaceAll(" +", " ")
+        .trim().split(" ");
+  }
+
+  /**
+   * Camel Case function.
+   *
+   * @param str input string
+   * @return a string in proper camel case format
+   */
+  private static String camelCase(String str) {
+    StringBuilder camel = new StringBuilder();
+    String[] words = splitWords(str);
+    int index = 0;
+    for (String word : words) {
+      if (index == 0) {
+        camel.append(word);
+      } else {
+        camel.append(word.substring(0, 1).toUpperCase()).append(word.substring(1));
+      }
+      index++;
+    }
+    return camel.toString();
+  }
+
+  /**
+   * Entry point.
+   *
+   * @param args command line arguments
+   */
+  public static void main(String[] args) {
+    var result1 = camelCase("_good_looking_blues_");
+    System.out.println(result1);
+
+    var result2 = camelCase("-=last-night-on-earth=-");
+    System.out.println(result2);
+
+  }
+
+}
