Encryption And Decryption Using AES 128

import java.util.Base64;
import java.util.Scanner;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

/**
 *  * Program to Encrypt/Decrypt String Using AES 128 bit Encryption Algorithm 
 */
public class EncryptDecryptString {

private static final String encryptionKey = "SUMTOTALEXPENSE!";
private static final String characterEncoding = "UTF-8";
private static final String cipherTransformation = "AES/CBC/PKCS5PADDING";
private static final String aesEncryptionAlgorithem = "AES";

/**
*      * Method for Encrypt Plain String Data      * @param plainText
*      * @return encryptedText     
*/
public static String encrypt(String plainText) {
String encryptedText = "";
try {
Cipher cipher = Cipher.getInstance(cipherTransformation);
byte[] key = encryptionKey.getBytes(characterEncoding);
SecretKeySpec secretKey = new SecretKeySpec(key, aesEncryptionAlgorithem);
IvParameterSpec ivparameterspec = new IvParameterSpec(key);
cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivparameterspec);
byte[] cipherText = cipher.doFinal(plainText.getBytes("UTF8"));
Base64.Encoder encoder = Base64.getEncoder();
encryptedText = encoder.encodeToString(cipherText);

} catch (Exception E) {
System.err.println("Encrypt Exception : " + E.getMessage());
}
return encryptedText;
}

/**
*      * Method For Get encryptedText and Decrypted provided String
*      * @param encryptedText      * @return decryptedText     
*/
public static String decrypt(String encryptedText) {
String decryptedText = "";
try {
Cipher cipher = Cipher.getInstance(cipherTransformation);
byte[] key = encryptionKey.getBytes(characterEncoding);
SecretKeySpec secretKey = new SecretKeySpec(key, aesEncryptionAlgorithem);
IvParameterSpec ivparameterspec = new IvParameterSpec(key);
cipher.init(Cipher.DECRYPT_MODE, secretKey, ivparameterspec);
Base64.Decoder decoder = Base64.getDecoder();
byte[] cipherText = decoder.decode(encryptedText.getBytes("UTF8"));
decryptedText = new String(cipher.doFinal(cipherText), "UTF-8");

} catch (Exception E) {
System.err.println("decrypt Exception : " + E.getMessage());
}
return decryptedText;
}

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter String : ");
String plainString = "pass.1word";// sc.nextLine();

String encyptStr = encrypt(plainString);
String decryptStr = decrypt(encyptStr);

System.out.println("Plain   String  : " + plainString);
System.out.println("Encrypt String  : " + encyptStr);
System.out.println("Decrypt String  : " + decryptStr);

String plainString2 = "titan#12";// sc.nextLine();

String encyptStr2 = encrypt(plainString2);
String decryptStr2 = decrypt(encyptStr2);

System.out.println("Plain   String  2: " + plainString2);
System.out.println("Encrypt String  2: " + encyptStr2);
System.out.println("Decrypt String  2: " + decryptStr2);

String plainString3 = "redab977";// sc.nextLine();

String encyptStr3 = encrypt(plainString3);
String decryptStr3 = decrypt(encyptStr3);

System.out.println("Plain   String  3: " + plainString3);
System.out.println("Encrypt String  3: " + encyptStr3);
System.out.println("Decrypt String  3: " + decryptStr3);

String plainString4 = "sreehari";// sc.nextLine();

String encyptStr4 = encrypt(plainString4);
String decryptStr4 = decrypt(encyptStr4);

System.out.println("Plain   String  3: " + plainString4);
System.out.println("Encrypt String  3: " + encyptStr4);
System.out.println("Decrypt String  3: " + decryptStr4);

String encryptedText = "EHMWYRpxFboP8cBgmg9f0w==";
String decrypted = decrypt(encryptedText);
System.out.println("Encrypted Text :" + encryptedText);
System.out.println("Decrypted value:" + decrypted);

}
}