一、项目结构描述

GoPage.java，这是项目的入口，它的最终目的是打开一个页面，新闻首页或者管理员登陆后的后台管理页面。它的任务是获取所有新闻并存入链表，并将新闻链表存入session，方便其他页面获取。获取flag参数，如果获取到了flag=“showlist”，则说明是管理员登录，将新闻数据送入后台管理页面，否则是未登录状态，将数据送入新闻首页浏览。
operateServlet.java,这是操作中心，包括管理员登录、新闻的增删改查。它会根据action参数去调用服务层相应的函数。
DBHelper.java,数据库助手类，本类直接与MySQL相联系，包括数据库的连接、查询、更新、以及最后的释放。
EncodingFilter.java,防止乱码的过滤器。
LoginFilter.java,用于拦截用户未经过登录，直接在地址栏中用url进入管理人员界面。
News.java,新闻的模型，包括新闻ID、新闻类别、新闻标题、新闻内容、新闻作者、更新时间几个属性。
NewsService.java,服务层。通过使用数据库助手类完成新闻的增、删、改、查函数以及用户登录验证函数。
Login.jsp,管理员登录页。
NewsCenter.jsp,新闻首页。
NewsInfo.jsp,新闻详情页。
operateNews.jsp,编辑页面，如编辑新闻和修改新闻。
ShowList.jsp，新闻管理中心页面。

二、截图

三、关键代码

operateServlet.java

package com.hedong.Control;import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/**1、这是操作中心，包括管理员登录、新闻的增删改查。* 2、对于不同的操作，程序会去调用服务层的相应功能。*//*** Servlet implementation class operateServlet*/
@WebServlet("/operateServlet")
public class operateServlet extends HttpServlet {private static final long serialVersionUID = 1L;/*** @see HttpServlet#HttpServlet()*/public operateServlet() {super();// TODO Auto-generated constructor stub}/*** @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)*/protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubresponse.setContentType("text/html;charset=UTF-8");response.setCharacterEncoding("utf-8");PrintWriter out=response.getWriter();//获取news参数和登录账号密码参数String action=request.getParameter("action");String myType=request.getParameter("newsType");String myTitle=request.getParameter("newsTitle");String myContent=request.getParameter("editorValue");String writer=request.getParameter("newsWriter");String myID=request.getParameter("newsID");String User=request.getParameter("userName");String Password=request.getParameter("passWord");		if(action.equals("add")) {com.hedong.Service.NewsService newsService=new com.hedong.Service.NewsService();//调用服务层添加数据newsService.InsertNews(myType,myTitle,myContent,writer);response.sendRedirect("/NewsWebsite/GoPage?flag=showlist");//重新打开新闻管理页面}else if(action.equals("dele")) {com.hedong.Service.NewsService newsService=new com.hedong.Service.NewsService();//调用服务层删除数据newsService.DeleteNews(myID);response.sendRedirect("/NewsWebsite/GoPage?flag=showlist");//重新打开新闻管理页面}else if(action.equals("edit")) {com.hedong.Service.NewsService newsService=new com.hedong.Service.NewsService();//调用服务层获取数据newsService.EditNews(myType,myTitle,myContent,writer,myID);response.sendRedirect("/NewsWebsite/GoPage?flag=showlist");//重新打开新闻管理页面}else if(action.equals("login")) {com.hedong.Service.NewsService newsService=new com.hedong.Service.NewsService();//调用服务层判断数据System.out.println(User+Password);boolean isLogin=newsService.isUser(User,Password);if(isLogin) {//这个字符串将会在js中被接收//1代表登录成功//2代表用户名或密码为空//3代表用户名或密码错误request.getSession().setAttribute("user",User);out.write("1");}else if(User==""||Password==""){out.write("2");}else {out.write("3");}out.close();}}/*** @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)*/protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubdoGet(request, response);}}

DBHelper.java

package com.hedong.DAL;import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;/*** 1、本类直接与MySQL相联系，包括数据库的连接、查询、更新、以及最后的释放。*/
public class DBHelper {// 此方法为获取数据库连接public static Connection getConnection() {Connection conn = null;try {String driver = "com.mysql.jdbc.Driver"; // 数据库驱动String url = "jdbc:mysql://localhost:3306/dbnews?useUnicode=true&characterEncoding=UTF-8";//数据库String user = "root"; // 用户名String password = "root"; // 密码Class.forName(driver);// 加载数据库驱动if (null == conn) {conn = DriverManager.getConnection(url, user, password);}} catch (ClassNotFoundException e) {System.out.println("Sorry,can't find the Driver!");e.printStackTrace();} catch (SQLException e) {e.printStackTrace();} catch (Exception e) {e.printStackTrace();}return conn;}/*** 增删改【Add、Del、Update】** @param sql* @return int*/public static int executeNonQuery(String sql) {int result = 0;Connection conn = null;Statement stmt = null;try {conn = getConnection();stmt = conn.createStatement();result = stmt.executeUpdate(sql);} catch (SQLException err) {err.printStackTrace();free(null, stmt, conn);} finally {free(null, stmt, conn);}return result;}/*** 增删改【Add、Delete、Update】** @param sql* @param obj* @return int*/public static int executeNonQuery(String sql, Object... obj) {int result = 0;Connection conn = null;PreparedStatement pstmt = null;try {conn = getConnection();pstmt = conn.prepareStatement(sql); for (int i = 0; i < obj.length; i++) {pstmt.setObject(i + 1, obj[i]);}result = pstmt.executeUpdate();} catch (SQLException err) {err.printStackTrace();free(null, pstmt, conn);} finally {free(null, pstmt, conn);}return result;}/*** 查【Query】** @param sql* @return ResultSet*/public static ResultSet executeQuery(String sql) {Connection conn = null;Statement stmt = null;ResultSet rs = null;try {conn = getConnection();stmt = conn.createStatement();rs = stmt.executeQuery(sql);} catch (SQLException err) {err.printStackTrace();free(rs, stmt, conn);}return rs;}/*** 查【Query】** @param sql* @param obj* @return ResultSet*/public static ResultSet executeQuery(String sql, Object... obj) {Connection conn = null;PreparedStatement pstmt = null;ResultSet rs = null;try {conn = getConnection();pstmt = conn.prepareStatement(sql);        for (int i = 0; i < obj.length; i++) {pstmt.setObject(i + 1, obj[i]);}rs = pstmt.executeQuery();} catch (SQLException err) {err.printStackTrace();free(rs, pstmt, conn);}return rs;}/*** 改【edit】** @param sql* @param obj* @return ResultSet*/public static int executeUpdate(String sql) {Connection conn = null;Statement stmt = null;ResultSet rs = null;int result=0;try {conn = getConnection();stmt = conn.createStatement();result = stmt.executeUpdate(sql);} catch (SQLException err) {err.printStackTrace();free(rs, stmt, conn);}return result;}/*** 判断记录是否存在** @param sql* @return Boolean*/public static Boolean isExist(String sql) {ResultSet rs = null;try {rs = executeQuery(sql);rs.last();int count = rs.getRow();if (count > 0) {return true;} else {return false;}} catch (SQLException err) {err.printStackTrace();free(rs);return false;} finally {free(rs);}}/*** 释放【ResultSet】资源** @param rs*/public static void free(ResultSet rs) {try {if (rs != null) {rs.close();}} catch (SQLException err) {err.printStackTrace();}}/*** 释放【Statement】资源** @param st*/public static void free(Statement st) {try {if (st != null) {st.close();}} catch (SQLException err) {err.printStackTrace();}}/*** 释放【Connection】资源** @param conn*/public static void free(Connection conn) {try {if (conn != null) {conn.close();}} catch (SQLException err) {err.printStackTrace();}}/*** 释放所有数据资源** @param rs* @param st* @param conn*/public static void free(ResultSet rs, Statement st, Connection conn) {free(rs);free(st);free(conn);}}

NewsService.java

package com.hedong.Service;import java.sql.ResultSet;
import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;/*** 1、服务层。包括新闻的增、删、改、查，以及用户账号密码验证。*/
public class NewsService {public void InsertNews(String myType,String myTitle,String myContent,String writer){SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");//设置日期格式String time= df.format(new Date());// new Date()为获取当前系统时间String sql="insert into news_tb (newsType,newsTitle,newsContent,newsWriter,newsTime) values ('"+myType+"','"+myTitle+"','"+myContent+"','"+writer+"','"+time+"')";int result= com.hedong.DAL.DBHelper.executeUpdate(sql);//调用数据修改层if(result>0){System.out.println("add sql over");}		  }public void DeleteNews(String newsID){String sql="delete from news_tb where newsID='"+newsID+"'";int result= com.hedong.DAL.DBHelper.executeUpdate(sql);//调用数据修改层if(result>0){System.out.println("del sql over");}		  }public void EditNews(String myType,String myTitle,String myContent,String writer,String myID){SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");//设置日期格式String time= df.format(new Date());// new Date()为获取当前系统时间String sql="update news_tb set newsType='"+myType+"',newsTitle='"+myTitle+"' , newsContent='"+myContent+"' , newsWriter='"+writer+"',newsTime='"+time+"' where newsID='"+myID+"'";int result= com.hedong.DAL.DBHelper.executeUpdate(sql);//调用数据修改层if(result>0){System.out.println("edit sql over");}		  }public boolean isUser(String user,String password) {String sql="select * from login_tb where userID='"+user+"' and passWord='"+password+"'";return com.hedong.DAL.DBHelper.isExist(sql);//调用数据判断层}public ArrayList<com.hedong.Model.News> QueryNews(){		  ArrayList<com.hedong.Model.News> arrNews=new ArrayList<com.hedong.Model.News>();String sql="select * from news_tb ";ResultSet rs= com.hedong.DAL.DBHelper.executeQuery(sql);//调用数据访问层System.out.println("excuete sql over");try {while(rs.next()){com.hedong.Model.News model=new com.hedong.Model.News();model.setNewsID(rs.getInt("newsID"));model.setNewsType(rs.getString("newsType"));model.setNewsTitle(rs.getString("newsTitle"));model.setNewsContent(rs.getString("NewsContent"));model.setNewsWriter(rs.getString("newsWriter"));model.setNewsTime(rs.getDate("newsTime"));arrNews.add(model);}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return arrNews;}}

四、总结

项目中使用了UEditor编辑器用于新闻的编辑，第一次使用没想到挺轻松，这是UEditor编辑器在项目中的使用方法：UEditor在JavaWeb中的应用
刚开始试图将新闻内容一起放在url后面作为参数传递给编辑修改页面，但结果是新闻内容中包含着一些特殊符号(使用了UEditor编辑器)导致url被提前截断。后来改进的方法是在GoPage.java中获取新闻存入链表，将链表存入session，其他页面只需要知道下标就能显示出正确新闻内容。