星期二 

import java.sql.*;

public class Dao {

    public void add(User user) throws Exception {
        String url = "jdbc:mysql://localhost:3306/db2?characterEncoding=utf-8";
        String username = "root";
        String password = "1234";
        Connection conn = DriverManager.getConnection(url, username, password);
        String sql = "INSERT INTO t_class(name,teachername,palce) values('" + user.getName() + "','" + user.getTeachername() + "','" + user.getPlace() + "')";
        Statement stmt = conn.createStatement();
        int count = stmt.executeUpdate(sql);
        System.out.println(count);
        stmt.close();
        conn.close();
    }
    public boolean check(User user) throws Exception {
        String url = "jdbc:mysql://localhost:3306/db2?characterEncoding=utf-8";
        String username = "root";
        String password = "1234";
        Connection conn = DriverManager.getConnection(url, username, password);
        String sql= "select * from t_class";
        boolean y=false;
        Statement stmt = conn.createStatement();
        ResultSet rs=stmt.executeQuery(sql);
        while (rs.next())
        {
            if((user.getTeachername()).equals(rs.getString(2)))
            y=true;
        }
        return y;
    }
}

定义Dao类用JDBC连接数据库

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/Servlet")
public class LoginServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;


    public LoginServlet() {
        super();

    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException{
        req.setCharacterEncoding("utf-8");
        String name = req.getParameter("name");
        String teachername = req.getParameter("teachername");
        String place = req.getParameter("place");
        System.out.println(name);
        //调用用户属性类
        User user = new User(name,teachername,place);
        //接受判断函数返回值
        Dao dao =new Dao();
        try {
            if(!dao.check(user))
            try {
                dao.add(user);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
            else
            {
                resp.sendRedirect("/nosubmit.jsp");
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        resp.setContentType("text/html;charset=UTF-8");
        resp.getWriter().println("<html>");
        resp.getWriter().println("<head>");
        resp.getWriter().println("<title>提交信息</title>");
        resp.getWriter().println("</head>");
        resp.getWriter().println("<body>");
        resp.getWriter().println("成功");
        resp.getWriter().println("</body>");
        resp.getWriter().println("</html>");
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req,resp);
    }

}

定义一个servlet用来处理jsp页面传来的数据

还有个User类和一个提交的jsp和提交失败的jsp

完成了用jsp页面导入数据到数据库了

posted @ 2023-10-10 14:00  umiQa  阅读(5)  评论(0)  编辑  收藏  举报