md5 加密 demo

import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; public class MD5Example { public static void main(String[] args) { String input Hello World; String md5Hash getMD5(input); System.out.println(原文 input); System.out.println(MD5 md5Hash); } public static String getMD5(String input) { try { // 1. 获取 MD5 算法实例 MessageDigest md MessageDigest.getInstance(MD5); // 2. 计算哈希值字节数组 byte[] hashBytes md.digest(input.getBytes()); // 3. 将字节数组转换为十六进制字符串 StringBuilder sb new StringBuilder(); for (byte b : hashBytes) { sb.append(String.format(%02x, b)); } return sb.toString(); } catch (NoSuchAlgorithmException e) { throw new RuntimeException(MD5算法不存在, e); } } }