javaweb入门笔记(5)-cookie和session

protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    HttpSession session = req.getSession();
    String sessionid = session.getId();
    Cookie cookie = new Cookie("JSESSIONID",sessionid);
    cookie.setPath("/s1");
    cookie.setMaxAge(30*60);
    resp.addCookie(cookie);
}

package org.iot.data;

import sun.misc.BASE64Encoder;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Random;

/**
 * Created by brian on 2016/1/27.
 */
public class TokenProcessor {//令牌
    /**
     * 1.构造方法私有
     * 2.自己创建一个
     * 3.对外暴露一个方法，允许获取上面创建的对象
     */

    private TokenProcessor(){}

    private  static final TokenProcessor instance = new TokenProcessor();

    public static TokenProcessor getInstance(){
        return instance;
    }

    public String genetateToken(){
        String token = System.currentTimeMillis()+new Random().nextInt()+"";

        try {
            MessageDigest md =  MessageDigest.getInstance("md5");
            byte [] md5 =  md.digest(token.getBytes());
            //base64编码
            BASE64Encoder encoder = new BASE64Encoder();
            return encoder.encode(md5);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
    }
}