private Connection connection = null;
    private PreparedStatement preparedStatement = null;
    private ResultSet resultSet = null;
    static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
    static final String DB_URL = "jdbc:mysql://localhost:3306/javaee?serverTimezone=UTC&&characterEncoding=utf8&useSSL=true";
    static final String USER = "root";
    static final String PASS = "123";

    public DataBase(){
        try {
            Class.forName(JDBC_DRIVER);
            // 打开链接
            System.out.println("connecting...");
            connection = DriverManager.getConnection(DB_URL,USER,PASS);
            if(!connection.isClosed())
                System.out.println("Succeeded connecting to the Database!");
        } catch(Exception e) {
            e.printStackTrace();
        }
    }

public class News {
    int newsID;
    String newstitle;
    String newsWriter;
    String newsTime;
    String newsCon;
    Date newsDate;
    //ID
    public int getNewsID(){
        return newsID;
    }
    public void setNewsID(int newsID){
        this.newsID = newsID;
    }
    //news
    public String getNewsTitle(){
        return newstitle;
    }
    public void setNewsTitle(String newstitle){
        this.newstitle = newstitle;
    }
    //作者
    public String getNewsWriter(){ return newsWriter; }
    public void setNewsWriter(String newsWriter){
        this.newsWriter = newsWriter;
    }
    //类型
    public String getNewsCon(){
        return newsCon;
    }
    public void setNewsCon(String newsCon){
        this.newsCon = newsCon;
    }
    //时间
    public Date getNewsDate(){
        return newsDate;
    }
    public void setNewsDate(Date newsDate){
        this.newsDate = newsDate;
    }
}

 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //response.setContentType("text/html; charset=UTF-8");
        //request.setCharacterEncoding("UTF-8");
        PrintWriter out = response.getWriter(); //获得输出流

        String name = request.getParameter("name");
        String password = URLEncoder.encode(request.getParameter("password"),"utf-8");//password转码
        DataBase db = new DataBase();
        if (db.login(name, password)) {
            Object o = request.getSession().getAttribute("onLine");
            String success = "
 用户名： " + name + "
 密码：" + password + " 
 登录成功 " + " 
 当前在线人数： " + o;
            Log_Cookie(name, password, response);//Cookie
            System.out.println(name);
            System.out.println(password);
            System.out.println(o);
            out.println(success);
            out.println();
            request.getRequestDispatcher("/show.html").forward(request,response);//跳转至新闻管理页面
        } else {
            System.out.println(name);
            System.out.println(password);
            String fail = "" +
                    "alert(‘用户名或密码错误！‘);" +
                    "location.href=‘login.html‘;";
            out.println(fail);
        }
        db.Clocec();
        out.close();
    }

public boolean login(String name,String psw) throws UnsupportedEncodingException {

        System.out.println("\n\n=======================HANDLING LOGIN\n\n");

        String select = "SELECT * FROM uname_psw WHERE uname = ? AND psw= ? ";
        System.out.println(select);
        boolean bool = false;
        try {
            preparedStatement = connection.prepareStatement(select);
            preparedStatement.setString(1,name);
            preparedStatement.setString(2,psw);
            resultSet = preparedStatement.executeQuery();
            if (resultSet.next()){
                bool = true;
                System.out.println("\n\nUSER EXISTS\n\n");
            }
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        return bool;
    }

class="left-menu">
    
"menu">
        
class="menu-list">
            "cursor:pointer" class="firsta">class="glyph-icon xlcd">首页class="sz">
            

"swpu.html" target="menuFrame">class="glyph-icon icon-chevron-right1">学校信息
                
"ShowNewsServlet" target="menuFrame">class="glyph-icon icon-chevron-right2">新闻管理
            


    

"http://java.sun.com/jsp/jstl/core" prefix="c"%>

   public List QueryNews() throws SQLException {
        String sql="select * from News";
        ResultSet rs=DataBase.executeQuery(sql);
        List lstNews=new ArrayList();
        while (rs.next()){
            News news=new News();
            news.setNewsID(rs.getInt("newsID"));
            news.setNewsTitle(rs.getString("newsTitle"));
            news.setNewsWriter(rs.getString("newsWriter"));
            news.setNewsCon(rs.getString("newsCon"));
            news.setNewsDate(rs.getDate("newsDate"));
            lstNews.add(news);
        }
        return lstNews;
    }

 

   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        NewsService newsService=new NewsService();
        try {
            List lstNews=newsService.QueryNews();
            for(News n:lstNews){
                System.out.print(n.getNewsCon());
            }
            request.setAttribute("lstNews",lstNews);
            request.getRequestDispatcher("show.jsp").forward(request,response);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }