String TpId = "Account id that given by system"; // must be string
                                String ReqTranportalId = "tpid="+ TpId +"&";
                                
                                String TpKey = "Account password that given by system"; // must be string
                                String ReqTranportalPassword = "tpkey="+ TpKey +"&";
                                
                                String TranAmount = "Amount without commission calculation"; // must be string
                                String ReqAmount = "amount="+TranAmount+"&";
                                
                                String TranFullAmount = "Amount with commission calculation"; // must be string
                                String ReqFullAmount = "fullamount="+TranFullAmount+"&";
                                
                                String paymenttype = "Card type"; // "1 mean Knet, 3 mean Visa/Master" must be string
                                String ReqPaymentType = "paymenttype="+ paymenttype +"&";
                                
                                String businesscode =  "business code that given by system"; // must be string
                                String ReqBusinesscode = "businesscode="+ businesscode +"&";
                                
                                String TranTrackid = "Unique key for identify transaction given by merchant"; // must be string
                                String ReqInvoiceKey = "invoicekey="+TranTrackid+"&";
                                
                                String udf1 = "return url must be give by merchant"; // must be string
                                String ReqUdf1 = "udf1="+ udf1 +"&";
                                String udf2 = "merchant can define , not required"; // must be string
                                String ReqUdf2 = "udf2="+ udf2 +"&";
                                String udf3 = "merchant can define , not required"; // must be string
                                String ReqUdf3 = "udf3="+ udf3 +"&";
                                
                                String paymentmedia = "Payment source"; // "0 mean mobile app, 1 mean web browser" must be string
                                String ReqPaymentMedia = "paymentmedia="+paymentmedia+"&";
                                
                                // Buyer details
                                String buyerMobile = "Buyer mobile number"; // must be string
                                String ReqPaymentBuyerMobile = "buyermobile="+buyerMobile+"&";
                                
                                String buyerEmail = "Buyer email"; // must be string
                                String ReqPaymentBuyerEmail = "buyeremail="+buyerEmail+"&";
                                
                                String buyerName = "Buyer name"; // must be string
                                String ReqPaymentBuyerName = "buyername="+buyerName+"&";
                                
                                String transactionRequestData = ReqPaymentMedia+ReqAmount+ReqFullAmount
                                +ReqPaymentType+ReqBusinesscode+ReqInvoiceKey+ReqUdf1+ReqUdf2+ReqUdf3
                                +ReqTranportalId+ReqTranportalPassword+ReqPaymentBuyerMobile
                                +ReqPaymentBuyerEmail+ReqPaymentBuyerName;
                                
                                String encriptData = call encryption method to encrypt data;
                                // Example
                                String encriptData = encryptAES(transactionRequestData); // need to call encryptAES in PayleGatewayHelper Service class
                                    

                                
                                    import java.math.BigDecimal;
                                    import javax.crypto.Cipher;
                                    import javax.crypto.spec.IvParameterSpec;
                                    import javax.crypto.spec.SecretKeySpec;
                                    import org.springframework.stereotype.Service;
                            
                                    @Service
                                    public class PayleGatewayHelper {
                                        private static final String HEX_DIGITS = "0123456789abcdef";
                                        private static final String RESOURCE_KEY = "**********"; // given by payle system
                            
                                        private String encryptAES(String encryptString) throws Exception {
                                            byte[] encryptedText = null;
                                            IvParameterSpec ivspec = null;
                                            SecretKeySpec skeySpec = null;
                                            Cipher cipher = null;
                                            byte[] text = null;
                                            String s = null;
                                            try {
                                                ivspec = new IvParameterSpec(RESOURCE_KEY.getBytes("UTF-8"));
                                                skeySpec = new SecretKeySpec(RESOURCE_KEY.getBytes("UTF-8"), "AES");
                                                cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
                                                cipher.init(Cipher.ENCRYPT_MODE, skeySpec, ivspec);
                                                text = encryptString.getBytes("UTF-8");
                                                encryptedText = cipher.doFinal(text);
                                                s = byteArrayToHexString(encryptedText);
                            
                                            } catch (Exception e) {
                                                e.printStackTrace();
                                            } finally {
                                                encryptedText = null;
                                                ivspec = null;
                                                skeySpec = null;
                                                cipher = null;
                                                text = null;
                                            }
                                            return s.toUpperCase();
                                        }
                            
                                        private static String byteArrayToHexString(byte[] data) {
                                            return byteArrayToHexString(data, data.length);
                                        }
                            
                                        private static String byteArrayToHexString(byte[] data, int length) {
                                            StringBuffer buf = new StringBuffer();
                            
                                            for (int i = 0; i != length; i++) {
                                                int v = data[i] & 0xff;
                            
                                                buf.append(HEX_DIGITS.charAt(v >> 4));
                                                buf.append(HEX_DIGITS.charAt(v & 0xf));
                                            }
                            
                                            return buf.toString();
                                        }
                            
                                        public static String decryptAES(String encryptedString) throws Exception {
                                            SecretKeySpec skeySpec = null;
                                            IvParameterSpec ivspec = null;
                                            Cipher cipher = null;
                                            byte[] textDecrypted = null;
                                            try {
                            
                                                byte[] b = hexStringToByteArray(encryptedString);
                                                skeySpec = new SecretKeySpec(RESOURCE_KEY.getBytes("UTF-8"), "AES");
                                                ivspec = new IvParameterSpec(RESOURCE_KEY.getBytes("UTF-8"));
                                                cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
                                                cipher.init(Cipher.DECRYPT_MODE, skeySpec, ivspec);
                                                textDecrypted = cipher.doFinal(b);
                                            } catch (Exception e) {
                                                e.printStackTrace();
                                            } finally {
                                                skeySpec = null;
                                                ivspec = null;
                                                cipher = null;
                                            }
                            
                                            return (new String(textDecrypted));
                                        }
                            
                                        private static byte[] hexStringToByteArray(String s) {
                                            int len = s.length();
                                            byte[] data = new byte[len / 2];
                                            for (int i = 0; i < len; i += 2) {
                                                data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4) + Character.digit(s.charAt(i + 1), 16));
                                            }
                                            return data;
                                        }
                                    }
                                
                            

                                
                                     PHP_AES_Cipher::$CIPHER_KEY_LEN) {
                                                $key = substr($str, 0, PHP_AES_Cipher::$CIPHER_KEY_LEN); //truncate to 16 bytes
                                            }
                                    
                                    
                                    
                                                    
                                            $encryptedPayload = bin2hex (openssl_encrypt($data, PHP_AES_Cipher::$OPENSSL_CIPHER_NAME, $key, OPENSSL_RAW_DATA, $key));
                                    
                                            return strtoupper($encryptedPayload);
                                    
                                        }
                                    
                                        /**
                                         * Decrypt data using AES Cipher (CBC) with 128 bit key
                                         *
                                         * @param type $key - key to use should be 16 bytes long (128 bits)
                                         * @param type $data - data to be decrypted in base64 encoding with iv attached at the end after a :
                                         * @return decrypted data
                                         */
                                        static function decrypt( $data) {
                                    
                                             
                                            if (strlen($key) < PHP_AES_Cipher::$CIPHER_KEY_LEN) {
                                                $key = str_pad("$key", PHP_AES_Cipher::$CIPHER_KEY_LEN, "0"); //0 pad to len 16
                                            } else if (strlen($key) > PHP_AES_Cipher::$CIPHER_KEY_LEN) {
                                                $key = substr($str, 0, PHP_AES_Cipher::$CIPHER_KEY_LEN); //truncate to 16 bytes
                                            }
                                    
                                            $hex2bin = hex2bin($data);
                                            $decryptedData = openssl_decrypt($hex2bin, PHP_AES_Cipher::$OPENSSL_CIPHER_NAME, $key, OPENSSL_RAW_DATA, $key);
                                    
                                            // $parts = explode(':', $data); //Separate Encrypted data from iv.
                                            // $decryptedData = openssl_decrypt(base64_decode($parts[0]), PHP_AES_Cipher::$OPENSSL_CIPHER_NAME, $key, OPENSSL_RAW_DATA, base64_decode($parts[1]));
                                    
                                            return $decryptedData;
                                        }
                                    
                                    }
                                    ?>