Fixed cipher code and ensured correct output

Cipher.java

@@ -1,61 +1,55 @@
 // This class is used for encrypting or decrypting strings using character mapping
-public class Cipher   
-{
+public class Cipher {
     // Strings for keeping the alphabets, one for the original letters and the other for the encrypted ones
     // encryption involves mapping from original to cipher, for each letter we locate the character in the
     // original string and replace it with the cipher alphabet letter at the same position
     public static final String ORIGINAL_ALPHABET = "abcdefghijklmnopqrstuvwxyz";
     public static final String CIPHER_ALPHABET = "dfxyhrklvwuasgimnojpqetbcz";
 
     public String encrypt(String inputString) {
-
-        // output string will be collected in this variable, one char at a time
+        // Output string will be collected in this variable, one char at a time
         String outputString = "";
-
-        // for all chars in the input string
-        for (int i = 0; i < inputString.length(); i++)   
-        {
 
+        // For all chars in the input string
+        for (int i = 0; i < inputString.length(); i++) {
+            // Append the encrypted version of the char to the output string
+            outputString += replaceChar(inputString.charAt(i), true);
         }
 
         return outputString;
     }
 
     public String decrypt(String inputString) {
-
-        // output string will be collected in this variable, one char at a time
+        // Output string will be collected in this variable, one char at a time
         String outputString = "";
-
-        replaceChar('a',true);
-
+
+        // For all chars in the input string
+        for (int i = 0; i < inputString.length(); i++) {
+            // Append the decrypted version of the char to the output string
+            outputString += replaceChar(inputString.charAt(i), false);
+        }
+
         return outputString;
     }
 
-    // replaces the given input char based on the given isEncrypt variable
+    // Replaces the given input char based on the given isEncrypt variable
     // if isEncrypt == true -> original to encrypted
     // if isEncrypt == false -> encrypted to original
-    // works only when the input char is included in our alphabet variables
-    // should not replace symbols or upper case letters, return input char in those cases
+    // Works only when the input char is included in our alphabet variables
+    // Should not replace symbols or upper-case letters, return input char in those cases
     private char replaceChar(char inputChar, boolean isEncrypt) {
-
-        if(isEncrypt) {
-            for (int i = 0; i < ORIGINAL_ALPHABET.length(); i++)   
-            {
-                if(ORIGINAL_ALPHABET.charAt(i) == inputChar) {
-
-                }
+        if (isEncrypt) {
+            int index = ORIGINAL_ALPHABET.indexOf(inputChar);
+            if (index != -1) {
+                return CIPHER_ALPHABET.charAt(index);
             }
-        }
-        else {
-            for (int i = 0; i < CIPHER_ALPHABET.length(); i++)   
-            {
-                if(CIPHER_ALPHABET.charAt(i) == inputChar) {
-                    return ORIGINAL_ALPHABET.charAt(i);
-                }
+        } else {
+            int index = CIPHER_ALPHABET.indexOf(inputChar);
+            if (index != -1) {
+                return ORIGINAL_ALPHABET.charAt(index);
             }
         }
-
-        // if we did not find it in the alphabet, then return the original char
+        // If the character is not found in our alphabets, return it as is
         return inputChar;
     }
-}   
+}