Java Web——增删改查之二界面后台java代码(转载)

/**

*

*/

/**

* @author Administrator

*

*/

package dao;

import java.sql.*;

public class DBConn {

/**

* 链接数据库

* @return

*/

public static Connection getConnection(){

Connection conn=null;

try {

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

conn=DriverManager.getConnection("jdbc:sqlserver://localhost:1433;DataBaseName=EstateDB","sa","123456");

} catch (Exception e) {

e.printStackTrace();

}

return conn;

}

}

BuildingDao.java

package dao;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.ArrayList;

import java.util.List;

import entity.Building;

public class BuildingDao {

/**

* 操作数据库命令链接

* 数据访问类

*/

private Connection conn;

private Statement state;

private ResultSet rs;

private PreparedStatement pre;

/**

* 查询全部

* @return

* @throws SQLException

*/

public List<Building> fill() throws SQLException {

List<Building> list = new ArrayList<Building>();

String sql = "select * from T_building";

conn = DBConn.getConnection();

state = conn.createStatement();

rs = state.executeQuery(sql);

Building p = null;

while (rs.next()) {

p = new Building();

p.setId(rs.getString("Id"));

p.setCompany(rs.getString("Company"));

p.setPhone(rs.getString("Phone"));

p.setDescription(rs.getString("Description"));

p.setStatus(rs.getString("Status"));

list.add(p);

}

rs.close();

state.close();

conn.close();

return list;

}

/**

* 根据Id查询

* @param Id

* @return

* @throws SQLException

*/

public Building fill(String Id) throws SQLException{

conn = DBConn.getConnection();

String sql="select * from T_building where Id=?";

pre = conn.prepareStatement(sql);

pre.setString(1, Id);

rs=pre.executeQuery();

Building p = null;

if(rs.next()){

p = new Building();

p.setId(rs.getString("Id"));

p.setCompany(rs.getString("Company"));

p.setPhone(rs.getString("Phone"));

p.setDescription(rs.getString("Description"));

p.setStatus(rs.getString("Status"));

}

rs.close();

pre.close();

conn.close();

return p;

}

/**

* 添加

* @param building

* @return

* @throws SQLException

*/

public int add(Building building) throws SQLException {

String sql = "insert T_building values ('" + building.getId() + "','"

+ building.getCompany() + "','" + building.getPhone() + "','"

+ building.getDescription() + "','" + building.getStatus()

+ "')";

System.out.println(sql);

conn = DBConn.getConnection();

state = conn.createStatement();

int result = state.executeUpdate(sql);

state.close();

conn.close();

return result;

}

/**

* 修改

* @param building

* @return

* @throws SQLException

*/

public int update(Building building) throws SQLException {

String sql="UPDATE T_building SET Company=?,Phone =?,"+"Description=?, Status=? WHERE Id=?";

conn=DBConn.getConnection();

pre = conn.prepareStatement(sql);

pre.setString(1, building.getCompany());

pre.setString(2, building.getPhone());

pre.setString(3, building.getDescription());

pre.setString(4, building.getStatus());

pre.setString(5, building.getId());

int count=pre.executeUpdate();

pre.close();

conn.close();

return count;

// TODO Auto-generated method stub

}

/**

* 根据ID删除一项

* @param Id

* @throws SQLException

*/

public void delete(String Id) throws SQLException {

String sql="delete from T_building where Id=?";

conn=DBConn.getConnection();

pre = conn.prepareStatement(sql);

pre.setString(1,Id);

pre.executeUpdate();

pre.close();

conn.close();

// TODO Auto-generated method stub

}

/**

* 多项选择Id删除

* @param Id

* @throws SQLException

*/

public void delete(String[] Id) throws SQLException {

conn = DBConn.getConnection();

String ids="'"+Id[0]+"'";

for(int i=1;i<Id.length;i++) {

ids=ids+",'"+Id[i]+"'";

}

String sql="delete from T_building where Id in ("+ids+")";

pre = conn.prepareStatement(sql);

pre.executeUpdate();

pre.close();

conn.close();

// TODO Auto-generated method stub

}

}

对啦，忘记创建实体类了。在entity包里面建实体类

Building.java

/**

*

*/

/**

* @author Administrator

*

*/

package entity;

public class Building {

/**

* 实体类

* 定义get ，set 属性

*/

private String Id;

private String Company;

private String Phone;

private String Description;

private String Status;

public String getId() {

return Id;

}

public void setId(String id) {

Id = id;

}

public String getCompany() {

return Company;

}

public void setCompany(String company) {

Company = company;

}

public String getPhone() {

return Phone;

}

public void setPhone(String phone) {

Phone = phone;

}

public String getDescription() {

return Description;

}

public void setDescription(String description) {

Description = description;

}

public String getStatus() {

return Status;

}

public void setStatus(String status) {

Status = status;

}

}

service服务

BuildingService.java

/**

*

*/

/**

* @author Administrator

*

*/

package service;

import java.sql.SQLException;

import java.util.List;

import dao.BuildingDao;

import entity.Building;

public class BuildingService{

/**

* 添加

* @param building

* @return

* @throws SQLException

*/

public int add(Building building) throws SQLException {

BuildingDao dao=new BuildingDao();

return dao.add(building);

}

/**

* 查询

* @return

* @throws SQLException

*/

public List<Building> fill() throws SQLException{

BuildingDao dao=new BuildingDao();

return dao.fill();

}

public Building fill(String Id) throws SQLException{

BuildingDao dao=new BuildingDao();

return dao.fill(Id);

}

/**

* 修改

* @param building

* @return

* @throws SQLException

*/

public int update(Building building) throws SQLException{

BuildingDao dao=new BuildingDao();

return dao.update(building);

}

/**

* 删除

* @param Id

* @throws SQLException

*/

public void delete(String Id) throws SQLException{

BuildingDao dao=new BuildingDao();

dao.delete(Id);;

}

public void delete(String[] Id) throws SQLException {

BuildingDao dao=new BuildingDao();

dao.delete(Id);

}

}

在action包里建servlet

BuildingServlet.java

/**

*

*/

/**

* @author Administrator

*

*/

package action;

import java.io.IOException;

import java.io.PrintWriter;

import java.sql.SQLException;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.swing.JApplet;

import service.BuildingService;

import entity.Building;

public class BuildingServlet extends javax.servlet.http.HttpServlet implements

javax.servlet.Servlet {

static final long serialVersionUID = 1L;

public BuildingServlet() {

super();

}

@Override

protected void doGet(HttpServletRequest request,

HttpServletResponse response) throws ServletException, IOException {

// TODO Auto-generated method stub

response.setCharacterEncoding("utf-8");

try {

start(request, response);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

@Override

protected void doPost(HttpServletRequest request,

HttpServletResponse response) throws ServletException, IOException {

// TODO Auto-generated method stub

request.setCharacterEncoding("utf-8");

try {

start(request, response);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

private void start(HttpServletRequest request, HttpServletResponse response)

throws Exception {

response.setCharacterEncoding("GBK");

response.setContentType("text/html;charset=utf-8");

BuildingService service = new BuildingService();

String action = request.getParameter("action");

String id = request.getParameter("id");

/**

* 添加

*/

if (action.equals("add")) {

response.setContentType("text/html;charset=utf-8");

String Id = request.getParameter("Id");

String Company = request.getParameter("Company");

String Phone = request.getParameter("Phone");

String Description = request.getParameter("Description");

String Status = request.getParameter("Status");

Building b = new Building();

b.setId(Id);

b.setCompany(Company);

b.setPhone(Phone);

b.setDescription(Description);

b.setStatus(Status);

BuildingService buildingService = new BuildingService();

try {

buildingService.add(b);

PrintWriter out = response.getWriter();

out.print("添加成功");

} catch (SQLException e) {

PrintWriter out = response.getWriter();

out.print("添加失败");

e.printStackTrace();

}

}

/**

* 查詢

*/

else if (action.equals("list")) {

try {

List<Building> buildingList = service.fill();

request.setAttribute("buildingList", buildingList);

request.getRequestDispatcher("buildingList.jsp").forward(

request, response);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

} else if (action.equals("list2")) {

String id1 = request.getParameter("id");

try {

Building building = service.fill(id1);

request.setAttribute("building", building);

request.getRequestDispatcher("buildingList.jsp").forward(

request, response);

} catch (Exception e) {

e.printStackTrace();

}

}

/**

* 修改

*/

else if (id != null&&action.equals("update")) {

try {

Building building = service.fill(id);

request.setAttribute("building", building);

request.getRequestDispatcher("buildingUpdate.jsp").forward(

request, response);

} catch (Exception e) {

e.printStackTrace();

}

} else if(action.equals("update2")){

String Id = request.getParameter("Id");

String Company = request.getParameter("Company");

String Phone = request.getParameter("Phone");

String Description = request.getParameter("Description");

String Status = request.getParameter("Status");

Building b = new Building();

b.setId(Id);

b.setCompany(Company);

b.setPhone(Phone);

b.setDescription(Description);

b.setStatus(Status);

BuildingService buildingService = new BuildingService();

try {

buildingService.update(b);

PrintWriter out = response.getWriter();

out.print("修改成功");

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

/**

* 删除

*/

if(action.equals("delete")) {

try {

List<Building> buildingDelete = service.fill();

request.setAttribute("buildingDelete", buildingDelete);

request.getRequestDispatcher("buildingDelete.jsp").forward(

request, response);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

else if(action.equals("delete2")) {

String[] ids=request.getParameterValues("Id");

// String id1=request.getParameter("id");

try {

//service.delete(id1);

service.delete(ids);

response.sendRedirect("BuildingServlet?action=delete");

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

else if(action.equals("delete3")) {

String id1=request.getParameter("id");

try {

service.delete(id1);

response.sendRedirect("BuildingServlet?action=delete");

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

}