MD5單次加密

import java.security.MessageDigest;
import java.util.Random;

import org.apache.commons.codec.binary.Hex;

/**
 * 
 * @author shilei
 *
 * @time 2019年6月13日 下午2:41:59
 *
 * @desc MD5加密
 */
public class MD5Utils {

	public static final String MD5_SALT = getSalt();

	/**
	 * @desc 加鹽MD5加密
	 */
	public static String getSaltMD5(String password) {

		password = md5Hex(password + MD5_SALT);

		char[] cs = new char[48];
		for (int i = 0; i < 48; i += 3) {
			cs[i] = password.charAt(i / 3 * 2);
			char c = MD5_SALT.charAt(i / 3);
			cs[i + 1] = c;
			cs[i + 2] = password.charAt(i / 3 * 2 + 1);
		}
		return String.valueOf(cs);
	}

	/**
	 * @desc 驗證加鹽後是否和原文一致
	 */
	public static boolean getSaltverifyMD5(String password, String md5str) {
		char[] cs1 = new char[32];
		char[] cs2 = new char[16];
		for (int i = 0; i < 48; i += 3) {
			cs1[i / 3 * 2] = md5str.charAt(i);
			cs1[i / 3 * 2 + 1] = md5str.charAt(i + 2);
			cs2[i / 3] = md5str.charAt(i + 1);
		}
		String Salt = new String(cs2);
		return md5Hex(password + Salt).equals(String.valueOf(cs1));
	}

	/**
	 * @desc 使用Apache的Hex類實現Hex(16進制字符串和)和字節數組的互轉
	 */
	private static String md5Hex(String str) {
		try {
			MessageDigest md = MessageDigest.getInstance("MD5");
			byte[] digest = md.digest(str.getBytes());
			return new String(new Hex().encode(digest));
		} catch (Exception e) {
			e.printStackTrace();
			System.out.println(e.toString());
			return "";
		}
	}

	/**
	 * @desc 生成一個16位的鹽
	 */
	private static String getSalt() {
		Random random = new Random();
		StringBuilder sBuilder = new StringBuilder(16);
		sBuilder.append(random.nextInt(99999999)).append(random.nextInt(99999999));
		int len = sBuilder.length();
		if (len < 16) {
			for (int i = 0; i < 16 - len; i++) {
				sBuilder.append("0");
			}
		}
		return sBuilder.toString();
	}

}