Java DES加密解密

import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

public class CryptKit {

private final static String DES = "DES";

public static void main(String args[]) throws Exception {
    String str = encrypt("The cold night", "12345678");
    System.out.println(str);
    String str2 = decrypt("63B121C4EA212F8BC74E8113BDFBFB81", "12345678");
    System.out.println(str2);
}

// 加密
public static byte[] encrypt(byte[] data, byte[] key) throws Exception {
    Cipher cipher = Cipher.getInstance(DES);
    DESKeySpec ds = new DESKeySpec(key);
    SecureRandom sr = new SecureRandom();
    SecretKeyFactory skfactory = SecretKeyFactory.getInstance(DES);
    SecretKey skey = skfactory.generateSecret(ds);
    cipher.init(Cipher.ENCRYPT_MODE, skey, sr);
    byte[] b = cipher.doFinal(data);
    return b;
}

// 加密
public static String encrypt(String data, String key) throws Exception {
    return byte2hex(encrypt(data.getBytes(), key.getBytes()));
}

// 解密
public static byte[] decrypt(byte[] data, byte[] key) throws Exception {
    Cipher cipher = Cipher.getInstance(DES);
    DESKeySpec ds = new DESKeySpec(key);
    SecureRandom sr = new SecureRandom();
    SecretKeyFactory skfactory = SecretKeyFactory.getInstance(DES);
    SecretKey skey = skfactory.generateSecret(ds);
    cipher.init(Cipher.DECRYPT_MODE, skey, sr);
    return cipher.doFinal(data);
}

// 解密
public static String decrypt(String data, String key) throws Exception {
    return new String(decrypt(hex2byte(data.getBytes()), key.getBytes()));
}

private static String byte2hex(byte[] b) {
    StringBuilder hs = new StringBuilder();
    String stmp;
    for (int n = 0; b != null && n < b.length; n++) {
        stmp = Integer.toHexString(b[n] & 0XFF);
        if (stmp.length() == 1)
            hs.append('0');
        hs.append(stmp);
    }
    return hs.toString().toUpperCase();
}

private static byte[] hex2byte(byte[] b) {
    if ((b.length % 2) != 0)
        throw new IllegalArgumentException();
    byte[] b2 = new byte[b.length / 2];
    for (int n = 0; n < b.length; n += 2) {
        String item = new String(b, n, 2);
        b2[n / 2] = (byte) Integer.parseInt(item, 16);
    }
    return b2;
}</pre>