import java.io.UnsupportedEncodingException; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; /** * @Author: JCccc * @CreateTime: 2018-10-30 * @Description: */ public class Md5Encrypt { private static final char[] DIGITS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; /** * 对字符串进行MD5加密 * * @param text 明文 * @return 密文 */ public static String md5(String text) { MessageDigest msgDigest = null; try { msgDigest = MessageDigest.getInstance("MD5"); } catch (NoSuchAlgorithmException e) { throw new IllegalStateException("System doesn't support MD5 algorithm."); } try { msgDigest.update(text.getBytes("UTF-8")); // 注意该接口是按照指定编码形式签名 } catch (UnsupportedEncodingException e) { throw new IllegalStateException("System doesn't support your EncodingException."); } byte[] bytes = msgDigest.digest(); String md5Str = new String(encodeHex(bytes)); return md5Str; } private static char[] encodeHex(byte[] data) { int l = data.length; char[] out = new char[l << 1]; // two characters form the hex value. for (int i = 0, j = 0; i < l; i++) { out[j++] = DIGITS[(0xF0 & data[i]) >>> 4]; out[j++] = DIGITS[0x0F & data[i]]; } return out; } } /* public static void main(String[] args) { System.out.println(Md5Encrypt.md5(Md5Encrypt.md5("123456" + "ffff"))); } } */