3DES的在Java的实现与DES类似，如下代码为3DES加密算法、CBC模式、PKCS5Padding填充方式的加密解密结果，参考代码如下所示：
import java.security.Key;import javax.crypto.Cipher;import javax.crypto.SecretKey;import javax.crypto.SecretKeyFactory;import javax.crypto.spec.DESedeKeySpec;import javax.crypto.spec.IvParameterSpec;import mons.codec.binary.Base64;/*** DES加密 解密算法* * @author peipei3514* @date -8-11 上午10:12:50*/public class DESEDEUtil {/** 算法名称 */public static final String KEY_ALGORITHM = "DESEDE";/** 算法名称/加密模式/填充方式 */public static final String CIPHER_ALGORITHM = "DESEDE/CBC/PKCS5Padding";/** 字符编码 ： 字符串转字节或字节转字符串时 一定要加上编码，否则可能出现乱码*/private final static String ENCODE = "UTF-8";/*** 加解密密钥<br/><br/>* 通过查看DESedeKeySpec源代码可以发现：3DES需要24字节(bytes)的秘钥*/private final static String DEFAULT_KEY = "A1B2C3D4E5F60708A1B2C3D4E5F60708A1B2C3D4E5F60708";/** Wrong IV length: must be 8 bytes long */private static String DES_IV = "JM23456*";/** 获取秘钥对象 */private static SecretKey keyGenerator(String keyStr) throws Exception {byte input[] = HexStringToBytes(keyStr);// 从原始密钥数据创建DESKeySpec对象// DESKeySpec desKey = new DESKeySpec(input);DESedeKeySpec KeySpec = new DESedeKeySpec(input);// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(KEY_ALGORITHM);SecretKey securekey = keyFactory.generateSecret(KeySpec);return securekey;}private static int parse(char c) {if (c >= 'a')return (c - 'a' + 10) & 0x0f;if (c >= 'A')return (c - 'A' + 10) & 0x0f;return (c - '0') & 0x0f;}/** 从十六进制字符串到字节(二进制 )数组转换 */private static byte[] HexStringToBytes(String hexstr) {byte[] results = new byte[hexstr.length() / 2];for (int i = 0; i < results.length; i++) {char c0 = hexstr.charAt(i * 2 + 0);char c1 = hexstr.charAt(i * 2 + 1);results[i] = (byte) ((parse(c0) << 4) | parse(c1));}return results;}/** 加密数据 */public static String encrypt(String data) throws Exception {// 获取秘钥对象Key deskey = keyGenerator(DEFAULT_KEY);// 实例化Cipher对象，它用于完成实际的加密操作Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);// 生成初始化向量IvParameterSpec iv = new IvParameterSpec(DES_IV.getBytes("UTF-8"));// 用密钥初始化Cipher对象，设置为加密模式cipher.init(Cipher.ENCRYPT_MODE, deskey, iv);// 执行加密操作byte[] results = cipher.doFinal(data.getBytes(ENCODE));// 执行加密操作。加密后的结果通常都会用Base64编码进行传输return Base64.encodeBase64String(results);}/** 解密数据 */public static String decrypt(String data) throws Exception {// 获取秘钥对象Key deskey = keyGenerator(DEFAULT_KEY);// 实例化Cipher对象，它用于完成实际的解密操作Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);// 生成初始化向量IvParameterSpec iv = new IvParameterSpec(DES_IV.getBytes("UTF-8"));// 初始化Cipher对象，设置为解密模式cipher.init(Cipher.DECRYPT_MODE, deskey, iv);// Base64解码byte[] results = Base64.decodeBase64(data);// 执行解密操作results = cipher.doFinal(results);// 变成字符串return new String(results, ENCODE);}public static void main(String[] args) throws Exception {String source = "123456";System.out.println("原文: " + source);String encryptData = encrypt(source);System.out.println("加密后: " + encryptData);String decryptData = decrypt(encryptData);System.out.println("解密后: " + decryptData);}}
