MD5

public class MD5Utils {/** * 使用md5的算法进行加密 */public static String md5(String plainText) {byte[] secretBytes = null;try {secretBytes = MessageDigest.getInstance("md5").digest(plainText.getBytes());} catch (NoSuchAlgorithmException e) {throw new RuntimeException("没有md5这个算法！");}String md5code = new BigInteger(1, secretBytes).toString(16);// 16进制数字// 如果生成数字未满32位，需要前面补0for (int i = 0; i < 32 - md5code.length(); i++) {md5code = "0" + md5code;}return md5code;}public static void main(String[] args) {System.out.println(md5("1234"));}}