程序实现目标:写到数据库即可
目录结构:
UserBean.java
package com.study.bean;
public class UserBean {
    
    private String username;
    private String password;
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    
}
UserDao.java
package com.study.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import com.study.bean.*;
import com.study.db.DBHelper;
public class UserDao {
    /**
     * 
     * 增加用户
     *
     */
    public void setUser(UserBean tuser)
    {
        String sql = "INSERT INTO T_USER VALUES(null,?,?)";// USER_NAME=?,USER_PWD=?;
        PreparedStatement pstat = null;
        Connection conn = new DBHelper().getConn();
        try {
            pstat = conn.prepareStatement(sql);
          
            pstat.setString(1, tuser.getUsername());
            pstat.setString(2, tuser.getPassword());
            
        } catch (SQLException e) {
            // TODO Auto-generated catch block
   
        } finally {
            try {
                if (conn != null)
                    conn.close();
                if (pstat != null)
                    pstat.close();
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    
    }
}
DBHelper.java
package com.study.db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
/**
 * 
 * 数据库连接类
 *
 */
public class DBHelper {
    private String driver = "org.gjt.mm.mysql.Driver";
    private String url = "jdbc:mysql://localhost:3306/first";
    private String user = "root";
    private String pwd = "0433gygy";
    
    public Connection getConn(){
        Connection conn = null;
        try {
            Class.forName(driver);
            conn = DriverManager.getConnection(url, user, pwd);
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return conn;
    }
    public static void main(String[] args) {
        System.out.println("DBHelper.main()" + new DBHelper().getConn());
    }
}
Register.java
package com.study.servlet;
import javax.servlet.http.*;
import javax.servlet.*;
import java.io.*;
import com.study.bean.*;
import com.study.dao.*;
public class Register extends HttpServlet{
    public void doGet(HttpServletRequest request,HttpServletResponse response)
    throws ServletException,IOException
    {    
        String un = request.getParameter("username");
        String pd = request.getParameter("password");
        
        
        UserBean Tuser = new UserBean();
        Tuser.setPassword(pd);
        Tuser.setUsername(un);
//        PrintWriter out = response.getWriter();
//        out.println("<html>");
//        out.println("<marquee>"+Tuser.getUsername()+"</marquee>");
//        out.println("</html>");
        UserDao dao = new UserDao();     
        dao.setUser(Tuser);
        
    }
     public void doPost(HttpServletRequest request, HttpServletResponse response)
     throws ServletException, IOException
   {
       doGet(request, response);
        
   }
}
web.xml
<servlet>
    <servlet-name>first</servlet-name>
    <servlet-class>com.study.servlet.Register</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>first</servlet-name>
    <url-pattern>/first</url-pattern>
    
  </servlet-mapping>
reg.jsp
<body>
    <form action="first" method = "post">
    username:<input type="text" name="username">
    password:<input type="password" name="password">
    <input type="submit" >
    </form>
  </body>
在reg.jsp 自己随便提交个表单.
程序很简单,没什么东西,结果就是写不到数据库,整个程序运行没有报错!望高手指点一下哪边有问题了.