DES加密解密

public class DESCoder {
public static final String KEY_ALGORITHM = "DES";
public static final String CIPHER_ALGORITHM = "DES/ECB/PKCS5Padding";

private Key toKey(byte[] key)
throws InvalidKeyException, NoSuchAlgorithmException,
InvalidKeySpecException {
DESKeySpec dks = new DESKeySpec(key);

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");

SecretKey secretKey = keyFactory.generateSecret(dks);

return secretKey;
}

public byte[] decrypt(byte[] data, byte[] key)
throws InvalidKeyException, NoSuchAlgorithmException,
InvalidKeySpecException, NoSuchPaddingException,
IllegalBlockSizeException, BadPaddingException {
Key k = toKey(key);

Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");

cipher.init(2, k);

return cipher.doFinal(data);
}

public byte[] encrypt(byte[] data, byte[] key)
throws Exception, NoSuchAlgorithmException, InvalidKeySpecException {
Key k = toKey(key);

Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");

cipher.init(1, k);

return cipher.doFinal(data);
}

public byte[] initKey() throws NoSuchAlgorithmException {
KeyGenerator kg = KeyGenerator.getInstance("DES");
kg.init(56);

SecretKey secretKey = kg.generateKey();

return secretKey.getEncoded();
}

public void test2() throws Exception {
byte[] key = initKey();

byte[] key2 = Base64.encode(key);
System.out.println("???????" + new String(key2));

String str1 = "??????????????";
byte[] b1 = str1.getBytes();
byte[] b2 = Base64.encode(b1);

byte[] b3 = encrypt(b2, key2);
System.out.println("?????????????????Base64?????????)???" +
new String(b3));

byte[] bb1 = Base64.encode(b3);
System.out.println("????????????" + new String(bb1));

byte[] bb2 = Base64.decode(bb1);
byte[] b4 = decrypt(bb2, key2);
System.out.println("?????????Base64???????????" + new String(b4));

byte[] b5 = Base64.decode(b4);
System.out.println("?????" + new String(b5));
}

public static void main(String[] args) throws Exception {
DESCoder d = new DESCoder();
String key = d.a();
String b = d.b("sjdlf", key);
String c = d.c(b, key);
System.out.println(key + " " + b + " " + c);
}

public String a() throws Exception {
byte[] key = initKey();

byte[] key2 = Base64.encode(key);

return new String(key2);
}

public String b(String s, String keyh) throws Exception {
String str1 = s;
byte[] b1 = str1.getBytes();
byte[] b2 = Base64.encode(b1);

byte[] b3 = encrypt(b2, keyh.getBytes());

byte[] bb1 = Base64.encode(b3);
String str = new String(bb1);

return str;
}

public String c(String miwen, String keyh) throws Exception {
byte[] bb2 = Base64.decode(miwen.getBytes());
byte[] b4 = decrypt(bb2, keyh.getBytes());

byte[] b5 = Base64.decode(b4);
String ss = new String(b5);

return ss;
}

public void saveKey(String str, File file) throws Exception {
FileWriter fw = new FileWriter(file);
BufferedWriter bw = new BufferedWriter(fw);
bw.write(str);
bw.flush();

if (bw != null) {
bw.close();
}
}

public String getFileKey(File file) throws Exception {
String str;
FileReader fr = new FileReader(file);
BufferedReader br = new BufferedReader(fr);
StringBuilder sb = new StringBuilder();

while ((str = br.readLine()) != null) {
sb.append(str);
}

if (fr != null) {
fr.close();
}

if (br != null) {
br.close();
}

return sb.toString();
}
}