FWe3gK2e

1public class Main
2{
3    public static void main(String[] args)
4    {
5        String plainText = "Testing encryption algorithms";
6
7        System.out.println("Text for encryption: " + plainText);
8
9        //DES
10
11        Encrypted des = Crypto.encrypt(plainText, Crypto.ALGORITHM_DES);
12
13        if(des != null)
14        {
15            System.out.println(des.toString());
16
17            String decrypted = Crypto.decrypt(des.getEncryptedText(), des.getKey(), des.getEncryptionMethod());
18
19            System.out.println("DES: Decrypted text: " + decrypted);
20        }
21
22        //3DES
23
24        Encrypted des3 = Crypto.encrypt(plainText, Crypto.ALGORITHM_3DES);
25
26        if(des3 != null)
27        {
28            System.out.println(des3.toString());
29
30            String decrypted = Crypto.decrypt(des3.getEncryptedText(), des3.getKey(), des3.getEncryptionMethod());
31
32            System.out.println("3DES: Decrypted text: " + decrypted);
33        }
34
35        //AES
36
37        Encrypted aes = Crypto.encrypt(plainText, Crypto.ALGORITHM_AES);
38
39        if(aes != null)
40        {
41            System.out.println(aes.toString());
42
43            String decrypted = Crypto.decrypt(aes.getEncryptedText(), aes.getKey(), aes.getEncryptionMethod());
44
45            System.out.println("AES: Decrypted text: " + decrypted);
46        }
47    }
48}
49
50import javax.crypto.*;
51import javax.crypto.spec.SecretKeySpec;
52import java.nio.charset.StandardCharsets;
53import java.security.InvalidKeyException;
54import java.security.NoSuchAlgorithmException;
55
56public class Crypto
57{
58    public static final String ALGORITHM_DES = "DES";
59    public static final String ALGORITHM_3DES = "DESede";
60    public static final String ALGORITHM_AES = "AES";
61
62    public static Encrypted encrypt(String text, String encryption)
63    {
64        try
65        {
66            //Generate key
67            KeyGenerator keyGenerator = KeyGenerator.getInstance(encryption);
68            SecretKey desKey = keyGenerator.generateKey();
69
70            //Initialize cipher
71            Cipher cipher = Cipher.getInstance(encryption);
72            cipher.init(Cipher.ENCRYPT_MODE, desKey);
73
74            //Convert text to byte array
75            byte[] bytes = text.getBytes(StandardCharsets.UTF_8);
76
77            //Encrypt
78            byte[] encryptedBytes = cipher.doFinal(bytes);
79
80            return new Encrypted(encryptedBytes, desKey.getEncoded(), encryption);
81        }
82        catch(NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | BadPaddingException | IllegalBlockSizeException e)
83        {
84            e.printStackTrace();
85        }
86
87        return null;
88    }
89
90    public static String decrypt(byte[] encryptedText, byte[] key, String encryption)
91    {
92        try
93        {
94            //Convert key
95            SecretKey desKey = new SecretKeySpec(key, 0, key.length, encryption);
96
97            //Initialize cipher
98            Cipher cipher = Cipher.getInstance(encryption);
99            cipher.init(Cipher.DECRYPT_MODE, desKey);
100
101            //Decrypt
102            byte[] decryptedBytes = cipher.doFinal(encryptedText);
103
104            return new String(decryptedBytes);
105        }
106        catch(NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | BadPaddingException | IllegalBlockSizeException e)
107        {
108            e.printStackTrace();
109        }
110
111        return null;
112    }
113}
114
115import java.nio.charset.StandardCharsets;
116
117public class Encrypted
118{
119    private byte[] encryptedText;
120    private byte[] key;
121    private String encryptionMethod;
122
123    public Encrypted(byte[] encryptedText, byte[] key, String encryptionMethod)
124    {
125        this.encryptedText = encryptedText;
126        this.key = key;
127        this.encryptionMethod = encryptionMethod;
128    }
129
130    public byte[] getEncryptedText()
131    {
132        return encryptedText;
133    }
134
135    public byte[] getKey()
136    {
137        return key;
138    }
139
140    public String getEncryptionMethod()
141    {
142        return encryptionMethod;
143    }
144
145    @Override
146    public String toString()
147    {
148        return encryptionMethod + ": " + "Encrypted Text: " + new String(encryptedText, StandardCharsets.UTF_8) + " Generated Key: " + new String(key, StandardCharsets.UTF_8);
149    }
150}