JAVAWEB 一一 userweb2（升级，servlet版,jstl和el）

Posted 2020-10-13 PoeticalJustice

tags:

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创建数据库和表

首先，创建一个web项目

然后引入jar包（jstl.jar和standard.jar是jstl和el包，在jsp页面中需要手动加 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 才有效）

创建jsp页面（doXX.jsp的代码全部转移到servlet里面）

创建包

创建接口

实现类

创建servlet

创建fiter过滤器

创建工具类（分页）

详细内容

首先创建一个登陆页面

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP \'login.jsp\' starting page</title>
    
	<meta http-equiv="pragma" content="no-cache">
	<meta http-equiv="cache-control" content="no-cache">
	<meta http-equiv="expires" content="0">    
	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
	<meta http-equiv="description" content="This is my page">
	
	<!--
	<link rel="stylesheet" type="text/css" href="styles.css">
	-->

  </head>
  
  <body>
    <form action="UserServlet" method="post">
    	用户名:<input type="text" name="username"/><br/>
    	密码:<input type="password" name="password3"/><br/>
    	<input type="submit" value="登陆"/>     
    	<input type="reset" value="重置"/>
    </form>    
  </body>
  
</html>

创建要跳转的页面 (充当半个控制器servlet)

dologin.jsp

<%@page import="com.user.service.impl.UserServiceImpl"%>
<%@page import="com.user.service.UserService"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
     
    <title>My JSP \'dologin.jsp\' starting page</title>
     
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
 
  </head>
   
  <body>
    <% 
    //dologin相当于一个servlet
    //设置前台页面参数  编码格式
        request.setCharacterEncoding("UTF-8");
        //获取前台页面参数
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        //  调用Service 层方法 判断是否成功
        UserService service = new UserServiceImpl();
        boolean islogin = service.isLogin(username, password);
         
        if(islogin){//登录成功 跳转到sucess.jsp页面 否则 跳转到login.jsp
        //转发
            request.getRequestDispatcher("success.jsp").forward(request,response);
             
        }else{//登录失败
            //重定向
            response.sendRedirect("Login.jsp");
        }
         
    %>
  </body>
</html>

将dologin.jsp的代码复制粘贴到

UserServlet.java

package com.user.servlet.user;

import java.io.IOException;


import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.user.service.UserService;
import com.user.service.impl.UserServiceImpl;

public class UserServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public UserServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
	   	//设置前台页面参数编码格式
    	request.setCharacterEncoding("UTF-8");
    	//获取前台页面参数
    	String username = request.getParameter("username");
    	String password = request.getParameter("password3");
    	//调用Sevice层方法  判断是否登陆成功
    	UserService service = new UserServiceImpl();
    	boolean isLogin = service.isLogin(username, password);
    	//如果登陆成功则跳转至success.jsp,否则跳转至login.jsp重新登陆
    	if(isLogin){
    	//转发
    		request.getRequestDispatcher("EmpServlet").forward(request, response);
    	}else{
    	 //重定向
    		response.sendRedirect("jsp/login.jsp");
    	}

	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doGet(request,response);

	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}

　成功跳转

　　success.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
     
    <title>My JSP \'success.jsp\' starting page</title>
     
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
 
  </head>
   
  <body>
    <h1>登录成功</h1><br>
  </body>
</html>

　　否则

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
     
    <title>My JSP \'Login.jsp\' starting page</title>
     
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
 
  </head>
   
  <body>
    <form action="jsp/dologin.jsp" method="post">
        用户名:<input type="text" name="username"/><br/>
        密码 :<input type="password" name="password"/> <br/>
        <input type="submit" value="登录"/>    
        <input type="reset" value="重置"/>
    </form>
  </body>
</html>

User

entity层

实体类

User.java

package com.user.entity;
/**
 * 
 * @author Administrator
 *
 */
public class User {
	
	private String username;
	private String password;
	private String job;
	private String email;
	private int age;
	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;
	}
	public String getJob() {
		return job;
	}
	public void setJob(String job) {
		this.job = job;
	}
	public String getEmail() {
		return email;
	}
	public void setEmail(String email) {
		this.email = email;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public User(String username, String password, String job, String email,
			int age) {
		super();
		this.username = username;
		this.password = password;
		this.job = job;
		this.email = email;
		this.age = age;
	}
	public User() {
		super();
	}
	
}

service层

接口 UserService.java

package com.user.service;

public interface UserService {

	public boolean isLogin(String username,String password);
}

实现类 UserServiceImpl.java

package com.user.service.impl;

import com.user.dao.UserDao;
import com.user.dao.impl.UserDaoImpl;
import com.user.entity.User;
import com.user.service.UserService;

public class UserServiceImpl implements UserService {

	public boolean isLogin(String username, String password) {
		
		UserDao userDao = new UserDaoImpl();
		
		User user = userDao.getUserByName(username);
		
		if(user!=null){
			
			String pwd= user.getPassword();
			
			if(pwd.equals(password)){
				
				return true;
			}
			return false;
			
		}else{
			return false;
		}
	}

}

dao层

接口 UserDao.java

package com.user.dao;

import com.user.entity.User;

public interface UserDao {
	
	public User getUserByName(String username);

}

实现类 UserDaoImpl.java

package com.user.dao.impl;

import java.sql.ResultSet;
import java.sql.SQLException;

import com.user.dao.BaseDao;
import com.user.dao.UserDao;
import com.user.entity.User;

public class UserDaoImpl implements UserDao {
	BaseDao dao = new BaseDao();
	public User getUserByName(String username) {
		//
		String sql ="select * from users where username = ?";
		Object [] obj = new Object[]{ username};
		ResultSet rs = dao.executeQuery(sql, obj);
		User user  =null;
		try {
			while(rs.next()){
				String password = rs.getString("password");
				String job = rs.getString("job");
				String email = rs.getString("email");
				int age = rs.getInt("age");
				user = new User(username, password, job, email, age);
			}
			return user;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			dao.closeConnection();
		}
		return null;
	}

}

basedao,java

package com.user.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;

/**
 * 数据库操作的基类
 * @author YangKe
 *
 */
public class BaseDao {
	
	protected Connection conn;
	protected PreparedStatement ps; 
	protected ResultSet rs;
	protected String sql;
	//获取连接
	public Connection getConnection(){
		try {
			//获取上下文对象
			Context ctx = new InitialContext();
			//从上下文中查找数据源
			DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/emp");
			//从数据源中获取连接
			conn = ds.getConnection();
		} catch (NamingException e) {
			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}
	
	//关闭连接释放资源
	public void closeConnection(){
		if(rs!=null){
			try {
				rs.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		if(ps!=null){
			try {
				ps.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		if(conn!=null){
			try {
				conn.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
	//通过JDBC来对数据库进行查询操作
	public ResultSet executeQuery(String sql, Object[] obj ){
		//获取连接
		conn = getConnection();
		try {
			//预编译SQL
			ps= conn.prepareStatement(sql);
			for (int i = 0; i < obj.length; i++) {
				//给占位符赋值
				ps.setObject(i+1, obj[i]);
			}
			//执行SQL语句，获取结果集
			rs = ps.executeQuery();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return rs;
	}
	//通过JDBC来对数据库进行更新操作
	public boolean executeUpdate(String sql, Object[] obj ){
		//获取连接
		conn = getConnection();
		try {
			//预编译SQL
			ps= conn.prepareStatement(sql);
			for (int i = 0; i < obj.length; i++) {
				//给占位符赋值
				ps.setObject(i+1, obj[i]);
			}
			//执行SQL语句，获取该更新语句实际影响的行数
			int count = ps.executeUpdate();
			//如果行数大于0,表示更新操作成功
			if(count>0){
				return true;
			//否则表示更新操作失败
			}else{
				return false;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return false;
	}
}

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
     
    <title>My JSP \'Login.jsp\' starting page</title>
     
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">   
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
 
  </head>
   
  <body>
    <form action="jsp/dologin.jsp" method="post">
        用户名:<input type="text" name="username"/><br/>
        密码 :<input type="password" name="password"/> <br/>
        <input type="submit" value="登录"/>    
        <input type="reset" value="重置"/>
    </form>
  </body>
</html>

dologin.jsp

<%@page import="com.user.service.impl.UserServiceImpl"%>
<%@page import="com.user.service.UserService"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
     
    <title>My JSP \'dologin.jsp\' starting page</title>
     
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
 
  </head>
   
  <body>
    <% 
    //dologin相当于一个servlet
    //设置前台页面参数  编码格式
        request.setCharacterEncoding("UTF-8");
        //获取前台页面参数
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        //  调用Service 层方法 判断是否成功
        UserService service = new UserServiceImpl();
        boolean islogin = service.isLogin(username, password);
         
        if(islogin){//登录成功 跳转到sucess.jsp页面 否则 跳转到login.jsp
        //转发
            request.getRequestDispatcher("success.jsp").forward(request,response);
             
        }else{//登录失败
            //重定向
            response.sendRedirect("Login.jsp");
        }
         
    %>
  </body>
</html>

将dologin.jsp的代码复制粘贴到

UserServlet.java

package com.user.servlet.user;

import java.io.IOException;


import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.user.service.UserService;
import com.user.service.impl.UserServiceImpl;

public class UserServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public UserServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
	   	//设置前台页面参数编码格式
    	request.setCharacterEncoding("UTF-8");
    	//获取前台页面参数
    	String username = request.getParameter("username");
    	String password = request.getParameter("password3");
    	//调用Sevice层方法  判断是否登陆成功
    	UserService service = new UserServiceImpl();
    	boolean isLogin = service.isLogin(username, password);
    	//如果登陆成功则跳转至success.jsp,否则跳转至login.jsp重新登陆
    	if(isLogin){
    	//转发
    		request.getRequestDispatcher("EmpServlet").forward(request, response);
    	}else{
    	 //重定向
    		response.sendRedirect("jsp/login.jsp");
    	}

	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doGet(request,response);

	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}

success .jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
     
    <title>My JSP \'success.jsp\' starting page</title>
     
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">   
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
 
  </head>
   
  <body>
    <h1>登录成功</h1><br>
  </body>
</html>

也可以直接跳转到别的页面比如list.jsp 一个雇员信息列表的页面但是这个页面的数据是从数据库查出来的(这样才是动态页面啊)

那么就需要再做一遍上面的步骤（创建Emp接口和实现类还有dolist页面 list页面）

Emp

entity层

Emp.java

package com.user.entity;

import java.util.Date;

public class Emp {
	private int empno;
	private String ename;
	private String job;
	private int mgr;
	private Date hiredate;
	private double sal;
	private double comm;
	private int deptno;
	
	public Emp() {
		super();
	}
	public Emp(int empno, String ename, String job, int mgr, Date hiredate,
			double sal, double comm, int deptno) {
		super();
		this.empno = empno;
		this.ename = ename;
		this.job = job;
		this.mgr = mgr;
		this.hiredate = hiredate;
		this.sal = sal;
		this.comm = comm;
		this.deptno = deptno;
	}

	public int getEmpno() {
		return empno;
	}
	public void setEmpno(int empno) {
		this.empno = empno;
	}
	public String getEname() {
		return ename;
	}
	public void setEname(String ename) {
		this.ename = ename;
	}
	public String getJob() {
		return job;
	}
	public void setJob(String job) {
		this.job = job;
	}
	public int getMgr() {
		return mgr;
	}
	public void setMgr(int mgr) {
		this.mgr = mgr;
	}
	public Date getHiredate() {
		return hiredate;
	}
	public void setHiredate(Date hiredate) {
		this.hiredate = hiredate;
	}
	public double getSal() {
		return sal;
	}
	public void setSal(double sal) {
		this.sal = sal;
	}
	public double getComm() {
		return comm;
	}
	public void setComm(double comm) {
		this.comm = comm;
	}
	public int getDeptno() {
		return deptno;
	}
	public void setDeptno(int deptno) {
		this.deptno = deptno;
	}
	

}

service层

接口 EmpService.java

/**
 * 
 */
package com.user.service;

import java.util.List;

import com.user.entity.Emp;

/**
 * @author YangKe
 *
 */
public interface EmpService {
	
	public List<Emp> getEmpList();
	
	public Emp getEmpById(int empno);
	
	public List<Emp> getEmpByName(String ename);
	
	public boolean addEmp(Emp emp);
	
	public boolean updateEmp(Emp emp);
	
	public boolean delEmpById(int empno);
	
	public List<Emp> getEmpList(int pageIndex,int pageSize);
	
	public int getTotalCount();
				
}

实现类 EmpServiceImpl

package com.user.service.impl;

import java.util.List;


import com.user.dao.EmpDao;
import com.user.dao.impl.EmpDaoImpl;
import com.user.entity.Emp;
import com.user.service.EmpService;

public class EmpServiceImpl implements EmpService {

	EmpDao empdao = new EmpDaoImpl();
	
	public List<Emp> getEmpList() {
		// TODO Auto-generated method stub
		
		return empdao.getEmpList();
	}

	public Emp getEmpById(int empno) {
		
		return empdao.getEmpByNo(empno);
	}

	public List<Emp> getEmpByName(String ename) {
		// TODO Auto-generated method stub
		return null;
	}

	public boolean addEmp(Emp emp) {
		return empdao.addEmp(emp);
	}

	public boolean updateEmp(Emp emp) {
		
		return empdao.updateEmp(emp);
	}

	public boolean delEmpById(int empno) {
		// TODO Auto-generated method stub
		return empdao.delEmpById(empno);
	}
	public List<Emp> getEmpList(int pageIndex,int pageSize){
		return empdao.getEmpList();
	}
	public int getTotalCount(){
		return empdao.getTotalCount();
	}

}

dao层

接口

EmpDao.java

package com.user.dao;

import java.util.List;

import com.user.entity.Emp;

public interface EmpDao {
	//
	public List<Emp> getEmpList();
	//
	public Emp getEmpByNo(int empno);
	//
	public List<Emp> getEmpByName(String name);
	//
	public boolean addEmp(Emp emp);
	//
	public boolean updateEmp(Emp emp);

	//
	public boolean delEmpById(int empno);
	//分页
	public List<Emp> getEmpList(int pageIndex,int pageSize);
	
	public int getTotalCount();
	
	

}

实现类

EmpDaoImpl.java

package com.user.dao.impl;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;




import com.user.dao.BaseDao;
import com.user.dao.EmpDao;

import com.user.entity.Emp;
import com.user.util.Page;

public class EmpDaoImpl implements EmpDao {
	Page page = new Page();
	//创建一个操作数据库的对象
	BaseDao basedao = new BaseDao();
	
	public List<Emp> getEmpList() {
		String sql = "select * from emp ";
		Object [] obj = new Object[]{};
		ResultSet rs = basedao.executeQuery(sql, obj);
		List<Emp> list = new ArrayList<Emp>();
		try {
			while(rs.next()){
				
				String ename = rs.getString("ename");
				int empno =rs.getInt("empno");
				String job = rs.getString("job");
				int mgr  = rs.getInt("mgr");
				Date hiredate = rs.getDate("hiredate");
				double sal = rs.getDouble("sal");
				double comm = rs.getDouble("comm");
				int deptno = rs.getInt("deptno");
				Emp emp = new Emp(empno, ename, job, mgr, hiredate, sal, comm, deptno);
				list.add(emp);
			}
			return list;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	
		return null;
	}

	public Emp getEmpByNo(int empno) {
		String sql = "select * from emp where empno=?";
		Object[]obj = new Object[]{empno};
		ResultSet rs = basedao.executeQuery(sql, obj);
		Emp emp =null;
		try {
			while(rs.next()){
				
				String ename = rs.getString("ename");
				empno =rs.getInt("empno");
				String job = rs.getString("job");
				int mgr  = rs.getInt("mgr");
				Date hiredate = rs.getDate("hiredate");
				double sal = rs.getDouble("sal");
				double comm = rs.getDouble("comm");
				int deptno = rs.getInt("deptno");
				emp = new Emp(empno, ename, job, mgr, hiredate, sal, comm, deptno);
				
			}
			return emp;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	
		return null;
	}

	public List<Emp> getEmpByName(String name) {
		// TODO Auto-generated method stub
		return null;
	}

	public boolean addEmp(Emp emp) {
		String sql = "insert into emp(empno,ename,job,mgr,sal,comm,deptno) values(?,?,?,?,?,?,?)";
		Object[] obj = new Object[] { emp.getEmpno(), emp.getEname(),
				emp.getJob(), emp.getMgr(), emp.getSal(), emp.getComm(),
				emp.getDeptno() };
		return basedao.executeUpdate(sql, obj);
	}

	public boolean updateEmp(Emp emp) {
		String sql = "update emp set ename=?,job=?,mgr=?,sal=?,comm=?,deptno=? where empno=?";
		Object [] obj = new Object[]{ emp.getEname(),
				emp.getJob(), emp.getMgr(), emp.getSal(), emp.getComm(),
				emp.getDeptno(),emp.getEmpno()};
		return basedao.executeUpdate(sql, obj);
	}

	public boolean delEmpById(int empno) {
		// TODO Auto-generated method stub
		String sql ="delete from emp where empno =?";
		Object[] obj = new Object[]{empno};
		return basedao.executeUpdate(sql, obj);
		
	}

	public List<Emp> getEmpList(int pageIndex, int pageSize) {
		String sql = "select*from(select e.*,rownum rn from (select * from emp)e)where rn>=? and rn<=?";
		int startRow = page.getStartRow(pageIndex, pageSize);
		int endRow = page.getEndRow(pageIndex, pageSize);
		Object[]obj= new Object[]{startRow,endRow};
		ResultSet rs = basedao.executeQuery(sql, obj);
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