string util

StringUtilities.java

@@ -7,19 +7,17 @@ public class StringUtilities {
     /**
      * @return `Hello World` as a string
      */
-    public static void Main(String[] args){
-        System.out.println("Hello World");
+    public String getHelloWorld(){
+        return "Hello World";
         }
-    }
-   
-
+    
     /**
      * @param firstSegment a string to be added to
      * @param secondSegment a string to add
      * @return the concatenation of two strings, `firstSegment`, and `secondSegment`
      */
     public String concatenation(String firstSegment, String secondSegment){
-        return null;
+        return firstSegment + secondSegment;
     }
 
     /**
@@ -28,7 +26,7 @@ public class StringUtilities {
      * @return the concatenation of an integer, `firstSegment`, and a String, `secondSegment`
      */
     public String concatenation(int firstSegment, String secondSegment){
-        return null;
+        return firstSegment + secondSegment;
     }
 
     /**
@@ -36,7 +34,8 @@ public class StringUtilities {
      * @return the first 3 characters of `input`
      */
     public String getPrefix(String input){
-        return null;
+       
+        return input.substring(0, 3);
     }
 
     /**
@@ -44,7 +43,7 @@ public class StringUtilities {
      * @return the last 3 characters of `input`
      */
     public String getSuffix(String input){
-        return null;
+        return input.substring(input.length() - 3);
     }
 
     /**
@@ -53,7 +52,9 @@ public class StringUtilities {
      * @return the equivalence of two strings, `inputValue` and `comparableValue`
      */
     public Boolean compareTwoStrings(String inputValue, String comparableValue){
-        return null;
+        
+        
+        return inputValue.equals(comparableValue);
     }
 
     /**
@@ -61,7 +62,8 @@ public class StringUtilities {
      * @return the middle character of `inputValue`
      */
     public Character getMiddleCharacter(String inputValue){
-        return null;
+        int mid = inputValue.length()/2;
+        return inputValue.charAt(mid);
     }
 
     /**
@@ -69,7 +71,10 @@ public class StringUtilities {
      * @return the first sequence of characters
      */
     public String getFirstWord(String spaceDelimitedString){
-        return null;
+        int x = spaceDelimitedString.indexOf(" ");
+        String firstWord = spaceDelimitedString.substring(0, x);
+        
+        return firstWord;
     }
 
     /**
@@ -77,7 +82,15 @@ public class StringUtilities {
      * @return the second word of a string delimited by spaces.
      */
     public String getSecondWord(String spaceDelimitedString){
-        return null;
+        int start = spaceDelimitedString.indexOf(" ") + 1;
+        int end = spaceDelimitedString.indexOf(" ", start);
+    
+    if (end == 1){
+        end = spaceDelimitedString.length( );
+    }
+    String secondWord = spaceDelimitedString.substring(start, end);
+    return secondWord;
+       
     }
 
     /**
@@ -85,7 +98,15 @@ public class StringUtilities {
      * @return an identical string with characters in reverse order.
      */
     public String reverse(String stringToReverse){
-        return null;
+        if (stringToReverse == null || stringToReverse.isEmpty()){
+            return stringToReverse;
+        }
+        String reverse = " ";
+        
+        for (int i = stringToReverse.length() - 1; i >=0; i--) {
+            reverse = reverse + stringToReverse.charAt(i);
+        }
+        return reverse;
     }
 
     /**
@@ -93,7 +114,8 @@ public class StringUtilities {
      * @return an identical string with spaces removed.
      */
     public String removeWhitespace(String input){
-        return null;
+        String newTrim = input.replaceAll("\\s","");
+        return newTrim;
     }
 
     /**
@@ -101,6 +123,7 @@ public class StringUtilities {
      * @return an identical string with spaces in the front and end removed.
      */
     public String trim(String input){
-        return null;
+        String trimmedString = input.trim();
+        return trimmedString;
     }
 }