jsp中的一个完整的增删改查

//index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

//这是regist.jsp

 

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@page import="com.dao.EmpDAO"%>
<%@page import="com.entity.Emp"%>
<%@page import="com.entity.Dep"%>

    姓名:

    性别:男
        女

    爱好:吃
     喝
     玩
     乐

    
 生日:

 部门:

//这是show.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@page import="com.entity.Emp"%>
注册员工 

 
   
   
   
   
   
 
 
  <%
    List emps = (List)request.getAttribute("emps");
    for (Emp e:emps) {
   %>
 
   
   
   
   
   
 
 <% } %>
 
 
 

编号	姓名	性别	部门	操作
<%= e.getEmpid() %>	<%= e.getEmpname() %>	<%= e.getEmpsex()==1 ?"男":"女" %>	<%= e.getDepname() %>	删除 |        修改

//这是update.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@page import="com.entity.Dep"%>
<%@page import="com.entity.Emp"%>

<%
  //取出在servlet保存的数据
  List deps = (List)request.getAttribute("deps");
  Emp        emp =    (Emp) request.getAttribute("emp");
%>

    编号:  readonly="readonly"> 

    姓名: 

    性别:男
         女 

    部门:
               <% for (Dep d:deps) { %>
                   <%=d.getDepname() %>
               <% } %>
               

        
        
   

//这是web.xml的代码
 xmlns="http://java.sun.com/xml/ns/javaee"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
 
    index.jsp
 
 
 
      servletLife
      com.servlets.ServletLife
      0
 
 
 
     servletLife
     /test.do
 
 
 
 
      EmpServlet
      com.servlets.EmpServlet
 
 
 
     EmpServlet
     /emp.do
 
 

//这是servlet的代码

import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

import javax.servlet.Servlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import com.dao.EmpDAO;
import com.entity.Emp;

public class EmpServlet implements Servlet {

 EmpDAO empDAO = new EmpDAO();

 public void destroy() {
  // TODO Auto-generated method stub
 }

 public ServletConfig getServletConfig() {
  // TODO Auto-generated method stub
  return null;
 }

 public String getServletInfo() {
  // TODO Auto-generated method stub
  return null;
 }

 public void init(ServletConfig config) throws ServletException {
  // TODO Auto-generated method stub

 }

 public void service(ServletRequest req, ServletResponse res)
   throws ServletException, IOException {
  req.setCharacterEncoding("utf-8");
  String p = req.getParameter("p");
  if (p.equals("getAllDep2RegistView")) {
   getAllDep2RegistView(req, res);
  } else if (p.equals("regist")) {
   regist(req, res);
  } else if (p.equals("getAllEmps")) {
   getAllEmps(req, res);
  } else if (p.equals("del")) {
   delEmp(req, res);
  } else if (p.equals("updateView")) {
            updateView(req, res);
  }
  else if (p.equals("update")){
   update(req, res);
  }

 }
 
 //保存修改
 public void update(ServletRequest request, ServletResponse res)
 throws ServletException, IOException {
        //编号 
  int empid = Integer.parseInt(request.getParameter("empid"));
  //姓名
  String empname = request.getParameter("empname");
  //性别
  int  empsex= Integer.parseInt(request.getParameter("empsex"));
  //部门
  int  depid  =Integer.parseInt(request.getParameter("depid"));
 
  //封装成Emp
  Emp emp = new Emp();
  emp.setEmpid(empid);
  emp.setEmpname(empname);
  emp.setDepid(depid);
  emp.setEmpsex(empsex);
 
  //修改
  int  n = empDAO.update(emp);
 
  if (n>0)
   getAllEmps(request, res);
  else{
   // 客户显示中文
   res.setContentType("text/html;charset=utf-8");
   // 得到输出流
   PrintWriter out = res.getWriter();
   // 输出
   out.write("");
  }
         
         
 }

 //根据员工id查找员工，并查找所有部门，保存起来，转到修改界面
 public void updateView(ServletRequest request, ServletResponse res)
   throws ServletException, IOException {
  int id = Integer.parseInt(request.getParameter("id"));
 
  //根据id查找对象
  Emp emp = empDAO.findById(id);
 
  //查找所有部门
  List deps = empDAO.getAllDep();
 
  //保存
  request.setAttribute("emp", emp);
  request.setAttribute("deps", deps);
 
  //转到修改界面
  request.getRequestDispatcher("/update.jsp").forward(request, res);
 

 }

 // 删除方法
 public void delEmp(ServletRequest request, ServletResponse res)
   throws ServletException, IOException {
  int id = Integer.parseInt(request.getParameter("id"));
  int n = empDAO.delEmp(id);
  if (n > 0)
   getAllEmps(request, res);
  else {
   // 客户显示中文
   res.setContentType("text/html;charset=utf-8");
   // 得到输出流
   PrintWriter out = res.getWriter();
   // 输出
   out.write("");
  }
 }

 // 取所有员工
 public void getAllEmps(ServletRequest request, ServletResponse res)
   throws ServletException, IOException {
  // 取所有员工
  List emps = empDAO.getAllEmps();
  request.setAttribute("emps", emps);
  request.getRequestDispatcher("/show.jsp").forward(request, res);

 }

 // 查部门转转到注册页面
 public void getAllDep2RegistView(ServletRequest request, ServletResponse res)
   throws ServletException, IOException {
  // 调用业务
  List deps = empDAO.getAllDep();

  // 保存部门
  request.setAttribute("deps", deps);

  // 转到注册页
  request.getRequestDispatcher("/regist.jsp").forward(request, res);
 }

 // 注册
 public void regist(ServletRequest req, ServletResponse res)
   throws ServletException, IOException {
  // 姓名
  String empname = req.getParameter("empname");

  // 性别
  String empsex = req.getParameter("empsex");

  // 爱好
  String[] emploves = req.getParameterValues("emploves");

  // 生日
  String empage = req.getParameter("empage");

  // 部门
  String depid = req.getParameter("depid");

  // 封装到Emp
  Emp emp = new Emp();
  emp.setDepid(Integer.parseInt(depid));
  emp.setEmpage(java.sql.Date.valueOf(empage));

  // 爱好
  StringBuffer sb = new StringBuffer();
  if (emploves != null) {
   for (String str : emploves) {
    sb.append(str).append(";");
   }
   emp.setEmploves(sb.toString());
  }
  emp.setEmpname(empname);
  emp.setEmpsex(Integer.parseInt(empsex));

  int n = empDAO.regist(emp);

  // 客户显示中文
  res.setContentType("text/html;charset=utf-8");
  // 得到输出对象，准备客户端写内容
  PrintWriter out = res.getWriter();

  if (n > 0) {
   // 输出
   out
     .write("");
  } else {
   out.write("");
  }

 }

}

//这是实体

public class Dep {
 private int depid;
 private String depname;

 public int getDepid() {
  return depid;
 }

 public void setDepid(int depid) {
  this.depid = depid;
 }

 public String getDepname() {
  return depname;
 }

 public void setDepname(String depname) {
  this.depname = depname;
 }

}
import java.sql.Date;

public class Emp extends Dep {
 private int empid;
 private String empname;
 private int empsex;
 private String emploves;
 private Date empage;
 
 public int getEmpid() {
  return empid;
 }

 public void setEmpid(int empid) {
  this.empid = empid;
 }

 public String getEmpname() {
  return empname;
 }

 public void setEmpname(String empname) {
  this.empname = empname;
 }

 public int getEmpsex() {
  return empsex;
 }

 public void setEmpsex(int empsex) {
  this.empsex = empsex;
 }

 public String getEmploves() {
  return emploves;
 }

 public void setEmploves(String emploves) {
  this.emploves = emploves;
 }

 public Date getEmpage() {
  return empage;
 }

 public void setEmpage(Date empage) {
  this.empage = empage;
 }

}

//这是dao

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import com.entity.Dep;
import com.entity.Emp;

public class EmpDAO {
 // 封装连接数据库
 public Connection getCon() {
  Connection con = null;
  try {
   Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
   con = DriverManager.getConnection(
     "jdbc:sqlserver://127.0.0.1:1433;DatabaseName=test", "sa",
     "sasa");
  } catch (ClassNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  return con;
 }

 // 修改员工
 public int update(Emp emp) {
  Connection con = getCon();
  String sql = "update emp set empname=?,empsex=?,depid=? where empid=?";
  int n = 0;
  try {
   PreparedStatement ps = con.prepareStatement(sql);
   ps.setObject(1, emp.getEmpname());
   ps.setObject(2, emp.getEmpsex());
   ps.setObject(3, emp.getDepid());
   ps.setObject(4, emp.getEmpid());
   n = ps.executeUpdate();
   con.close();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  return n;
 }

 // 取所有部门
 public List getAllDep() {
  Connection con = getCon();
  List list = new ArrayList();
  String sql = "select * from dep";
  try {
   PreparedStatement ps = con.prepareStatement(sql);
   ResultSet rs = ps.executeQuery();

   while (rs.next()) {
    int depid = rs.getInt("depid");
    String depname = rs.getString("depname");
    Dep dep = new Dep();
    dep.setDepid(depid);
    dep.setDepname(depname);
    list.add(dep);
   }
   con.close();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }

  return list;

 }

 // 保存注册
 public int regist(Emp emp) {
  Connection con = getCon();
  String sql = "insert into emp(empname,empsex,emploves,empage,depid) values(?,?,?,?,?)";
  int n = 0;
  try {
   PreparedStatement ps = con.prepareStatement(sql);
   ps.setObject(1, emp.getEmpname());
   ps.setObject(2, emp.getEmpsex());
   ps.setObject(3, emp.getEmploves());
   ps.setObject(4, emp.getEmpage());
   ps.setObject(5, emp.getDepid());
   n = ps.executeUpdate();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  return n;

 }

 // 删除员工
 public int delEmp(int id) {
  Connection con = getCon();
  String sql = "delete from emp where empid=?";
  int n = 0;
  try {
   PreparedStatement ps = con.prepareStatement(sql);
   ps.setObject(1, id);
   n = ps.executeUpdate();
   con.close();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }

  return n;
 }

 // 取所有员工
 public List getAllEmps() {
  List list = new ArrayList();
  Connection con = getCon();
  String sql = "select * from emp join dep on emp.depid=dep.depid";
  try {
   PreparedStatement ps = con.prepareStatement(sql);
   ResultSet rs = ps.executeQuery();
   while (rs.next()) {
    Emp emp = new Emp();
    int empid = rs.getInt("empid");
    String empname = rs.getString("empname");
    int empsex = rs.getInt("empsex");
    String depname = rs.getString("depname");
    emp.setDepname(depname);
    emp.setEmpname(empname);
    emp.setEmpid(empid);
    emp.setEmpsex(empsex);

    list.add(emp);

   }
   con.close();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }

  return list;

 }

 // 根据id查找员工
 public Emp findById(int id) {
  Connection con = getCon();
  String sql = "select * from emp where empid=?";
  try {
   PreparedStatement ps = con.prepareStatement(sql);
   ps.setObject(1, id);
   ResultSet rs = ps.executeQuery();
   if (rs.next()) {
    Emp emp = new Emp();
    int empid = rs.getInt("empid");
    String empname = rs.getString("empname");
    int empsex = rs.getInt("empsex");
    int depid = rs.getInt("depid");
    emp.setDepid(depid);
    emp.setEmpname(empname);
    emp.setEmpid(empid);
    emp.setEmpsex(empsex);

    return emp;
   }
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } finally {
   try {
    con.close();
   } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }

  return null;

 }

}

 

//这是servlet的一个生命周期

import java.io.IOException;

import javax.servlet.Servlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class ServletLife implements Servlet {
 public ServletLife(){
  System.out.println("实例化");
 }

 public void destroy() {
  // TODO Auto-generated method stub
        System.out.println("死亡");
 }

 public ServletConfig getServletConfig() {
  // TODO Auto-generated method stub
  return null;
 }

 public String getServletInfo() {
  // TODO Auto-generated method stub
  return null;
 }

 public void init(ServletConfig arg0) throws ServletException {
  // TODO Auto-generated method stub
  System.out.println("初始化");

 }

 public void service(ServletRequest arg0, ServletResponse arg1)
   throws ServletException, IOException {
  // TODO Auto-generated method stub
  System.out.println("服务");

 }

}