EHD8gRza

1package Cryptography;
2
3import java.io.UnsupportedEncodingException;
4import java.security.MessageDigest;
5import java.security.NoSuchAlgorithmException;
6import java.security.SecureRandom;
7import java.security.spec.AlgorithmParameterSpec;
8import java.security.spec.InvalidKeySpecException;
9import java.security.spec.KeySpec;
10import java.util.Arrays;
11
12import javax.crypto.Cipher;
13import javax.crypto.SecretKey;
14import javax.crypto.SecretKeyFactory;
15import javax.crypto.spec.IvParameterSpec;
16import javax.crypto.spec.PBEKeySpec;
17import javax.crypto.spec.SecretKeySpec;
18import javax.print.DocFlavor.STRING;
19
20import org.apache.commons.codec.binary.Base64;
21
22public class AES {
23
24    private SecretKeySpec secretKey;
25    private byte[] key;
26
27    private String decryptedString;
28    private String encryptedString;
29
30    public void setKey(String myKey) {
31
32        MessageDigest sha = null;
33        try {
34            key = myKey.getBytes("UTF-8");
35            //System.out.println(key.length);
36            sha = MessageDigest.getInstance("SHA-1");
37            key = sha.digest(key);
38            key = Arrays.copyOf(key, 16); // use only first 128 bit
39            //System.out.println(key.length);
40            //System.out.println(new String(key, "UTF-8"));
41            secretKey = new SecretKeySpec(key, "AES");
42
43        } catch (NoSuchAlgorithmException e) {
44            // TODO Auto-generated catch block
45            e.printStackTrace();
46        } catch (UnsupportedEncodingException e) {
47            // TODO Auto-generated catch block
48            e.printStackTrace();
49        }
50
51    }
52
53    private String getDecryptedString() {
54        return decryptedString;
55    }
56
57    private void setDecryptedString(String decryptedString) {
58        this.decryptedString = decryptedString;
59    }
60
61    private String getEncryptedString() {
62        return encryptedString;
63    }
64
65    private void setEncryptedString(String encryptedString) {
66        this.encryptedString = encryptedString;
67    }
68
69    public String encrypt(String strToEncrypt) {
70        try {
71            Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
72
73            cipher.init(Cipher.ENCRYPT_MODE, secretKey);
74
75            setEncryptedString(Base64.encodeBase64String(cipher.doFinal(strToEncrypt.getBytes("UTF-8"))));
76           
77            return getEncryptedString();
78
79        } catch (Exception e) {
80
81            System.out.println("Error while encrypting: " + e.toString());
82        }
83        return null;
84
85    }
86
87    public String decrypt(String strToDecrypt) {
88        try {
89            Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5PADDING");
90
91            cipher.init(Cipher.DECRYPT_MODE, secretKey);
92            setDecryptedString(new String(cipher.doFinal(Base64.decodeBase64(strToDecrypt))));
93            return getDecryptedString();
94
95        } catch (Exception e) {
96
97            System.out.println("Error while decrypting: " + e.toString());
98
99        }
100        return null;
101    }
102
103    public static void main(String args[]) {
104
105        final String strToEncrypt = "My text to encrypt";
106        final String strPssword = "encryptor key";
107        AES aes = new AES();
108        aes.setKey(strPssword);
109
110        aes.encrypt(strToEncrypt.trim());
111
112        System.out.println("String to Encrypt: " + strToEncrypt);
113        System.out.println("Encrypted: " + aes.getEncryptedString());
114
115        final String strToDecrypt = aes.getEncryptedString();
116        aes.decrypt(strToDecrypt.trim());
117
118        System.out.println("String To Decrypt : " + strToDecrypt);
119        System.out.println("Decrypted : " + aes.getDecryptedString());
120
121    }
122
123}