Added comments

AESEncryption.java

@@ -11,7 +11,6 @@ public class AESEncryption
       Scanner input = new Scanner(System.in);
       System.out.print("Enter E for encyrption or D for decryption: ");
       String a = input.nextLine();
-
       if(a.equals("E"))
       {
          encrypt();
@@ -23,35 +22,43 @@ public class AESEncryption
    }
    public static void encrypt()
    {
-
       Scanner input = new Scanner(System.in);
       System.out.print("Enter the file name: ");
       String fileName = input.nextLine();
       File file = new File(fileName);
       try
       {
-
+         // create secret key
          KeyGenerator keyGen = KeyGenerator.getInstance("AES");
          keyGen.init(128);
          SecretKey key = keyGen.generateKey();
 
+         // initialize aes encryption object
          Cipher cipher = Cipher.getInstance("AES");
          cipher.init(Cipher.ENCRYPT_MODE, key);
 
+         // read in bytes
          FileInputStream fis = new FileInputStream(file);
          byte[] byteArray = new byte[(int)file.length()];
          int buffer = fis.read(byteArray);
+
+         // encrypt bytes
          byte[] bArray = cipher.doFinal(byteArray);
 
+         // write bytes (in place)
          FileOutputStream fos = new FileOutputStream(file);
          fos.write(bArray);
 
+         // write key to file
          FileOutputStream encodedKey = new FileOutputStream("key.txt");
          byte[] keys = key.getEncoded();
          encodedKey.write(keys);
 
+         // close result file
          fis.close();
          fos.close();
+
+         // close key file
          encodedKey.close();
       }
       catch(FileNotFoundException fnfe)
@@ -82,46 +89,43 @@ public class AESEncryption
       {
          System.out.println("the given key is inappropriate for initializing this cipher");
       }
-   }//end of encrypt method
+   }
    public static void decrypt()
-   {
       Scanner input = new Scanner(System.in);
       System.out.print("Enter the file name of whats to be decrypted: ");
       String fileName = input.nextLine();
-
       System.out.print("Enter the file name of the key: ");
       String keyName = input.nextLine();
-
       File encryptedFile = new File(fileName);
       File encryptedKey = new File(keyName);
-
       try
       {
-
-
+         // load all data
          FileInputStream fisKey = new FileInputStream(encryptedKey);
          FileInputStream fisFile = new FileInputStream(encryptedFile);
          FileOutputStream fos = new FileOutputStream("decryptedFile.txt");
 
+         // initialize output byte array
          byte[] fileArray = new byte[(int)encryptedFile.length()];
          int buffer2 = fisFile.read(fileArray);
 
+         // initialize key byte array
          byte[] keyBytes = new byte[(int)encryptedKey.length()];
          int buffer = fisKey.read(keyBytes);
 
+         // construct secret key from key bytes
          SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
 
+         // initialize cipher and decrypt
          Cipher cipher = Cipher.getInstance("AES");
          cipher.init(Cipher.DECRYPT_MODE, key);
          byte[] cipherBytes = cipher.doFinal(fileArray);
 
-
+         // write to file
          fos.write(cipherBytes);
-
          fisKey.close();
          fos.close();
          fisFile.close();
-
       }
       catch(FileNotFoundException fnfe)
       {
@@ -155,6 +159,5 @@ public class AESEncryption
       {
          System.out.println("bad or invalid padding/block");
       }
-
    }
-}
+}