JavaEE学习总结（十四）— 人工智能微博

2022-10-13 07:44:36

一、数据库与表

人工智能微博(blog)

note(id,bt,nr);
微博信息(编号，标题，内容）

列表
添加

数据库脚本

/*

Navicat MySQL Data Transfer

Source Server         : localhost

Source Server Version : 50506

Source Host           : localhost:3306

Source Database       : blog

Target Server Type    : MYSQL

Target Server Version : 50506

File Encoding         : 65001

Date: 2017-07-13 08:58:01

*/

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------

-- Table structure for `wb`

-- ----------------------------

DROP TABLE IF EXISTS `wb`;

CREATE TABLE `wb` (

  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '编号',

  `bt` varchar(128) NOT NULL COMMENT '标题',

  `nr` text COMMENT '内容',

  PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;

-- ----------------------------

-- Records of wb

-- ----------------------------

INSERT INTO `wb` VALUES ('', '微软建立新人工智能实验室 开发多用途学习系统', '微软公司凤凰科技讯据彭博社北京时间7月12日报道,微软公司将建立一个新研究实验室,专注于人工智能(AI),目标是开发出更为多用途的学习系统');

INSERT INTO `wb` VALUES ('', '人工智能来袭 金融行业迎来下岗潮', '“在金融圈和用户教育上,对人工智能还未完全信任之前,我们只能采取人肉智能(HI)和人工智能(AI)相结合的方式”,朱明杰称,他们会机器先出一些模型,在专业的风控从');

INSERT INTO `wb` VALUES ('', '即便取代脑力劳动AI还不能“打动”人心', '但AI革命不同, AI取代脑力劳动,将让人类转向创造性、情感性劳动,这些素质是每一个体都具有的。 事实上,人工智能导致失业,还属于一种弱人工智能观念。有人煞有介');

INSERT INTO `wb` VALUES ('', 'Google 设立风投公司扶持 AI 新创团队', 'Google 在 AI 上的野心人尽皆知,但要让行业更好地发展,光有他们自己的力量是不够的。因此在最近他们新成立了一间名为 Gradient');

INSERT INTO `wb` VALUES ('', 'AI来临,失业大势难以避免', 'AI来临,我们需要担心失业吗? 据斯坦福大学人工智能与伦理学教授卡普兰的一项统计,美国注册在案的720个职业中,将有47%被人工智能取代。未来10年机器人将取代1500万');

二、创建项目

三、添加驱动

四、创建实体层（Bean）

package com.weibo;

/**微博Bean*/

public class Wb {

    /**编号*/

    private int id;

    /**标题*/

    private String bt;

    /**内容*/

    private String nr;

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

    public String getBt() {

        return bt;

    }

    public void setBt(String bt) {

        this.bt = bt;

    }

    public String getNr() {

        return nr;

    }

    public void setNr(String nr) {

        this.nr = nr;

    }

}

五、创建数据访问层（Dao）

5.1、JDBCUtil辅助类

package com.dao;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.ResultSetMetaData;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

public class JDBCUtils {

    public static String DRIVER="com.mysql.jdbc.Driver";

    public static String URL="jdbc:mysql://127.0.0.1:3306/blog?useUnicode=true&characterEncoding=UTF-8";

    public static String USER_NAME="root";

    public static String PASSWORD="";

    //加载驱动

    static {

        try {

            Class.forName(DRIVER);

        } catch (ClassNotFoundException e) {

            e.printStackTrace();

        }

    }

    private JDBCUtils() {

    }

    /**

     * 获得连接

     *

     * @return

     */

    public static Connection getconnnection() {

        Connection con = null;

        try {

            con = DriverManager.getConnection(URL, USER_NAME, PASSWORD);

        } catch (SQLException e) {

            e.printStackTrace();

        }

        return con;

    }

    /**

     * 关闭连接

     *

     * @param rs

     * @param st

     * @param con

     */

    public static void close(ResultSet rs, Statement st, Connection con) {

        try {

            try {

                if (rs != null) {

                    rs.close();

                }

            } finally {

                try {

                    if (st != null) {

                        st.close();

                    }

                } finally {

                    if (con != null)

                        con.close();

                }

            }

        } catch (SQLException e) {

            e.printStackTrace();

        }

    }

    /**

     * 关闭连接

     *

     * @param rs

     */

    public static void close(ResultSet rs) {

        Statement st = null;

        Connection con = null;

        try {

            try {

                if (rs != null) {

                    st = rs.getStatement();

                    rs.close();

                }

            } finally {

                try {

                    if (st != null) {

                        con = st.getConnection();

                        st.close();

                    }

                } finally {

                    if (con != null) {

                        con.close();

                    }

                }

            }

        } catch (SQLException e) {

            e.printStackTrace();

        }

    }

    /**

     * 关闭连接

     *

     * @param st

     * @param con

     */

    public static void close(Statement st, Connection con) {

        try {

            try {

                if (st != null) {

                    st.close();

                }

            } finally {

                if (con != null)

                    con.close();

            }

        } catch (SQLException e) {

            e.printStackTrace();

        }

    }

    /**

     * insert/update/delete

     * 增加/更新/删除

     *

     * @param sql 数据库语句

     * @param args 可变参数（可以不带参数，可以带0-n个参数）

     * @return

     */

    public static int update(String sql, Object... args) {

        int result = 0;

        Connection con = getconnnection();

        PreparedStatement ps = null;

        try {

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            result = ps.executeUpdate();

        } catch (SQLException e) {

            e.printStackTrace();

        } finally {

            close(ps, con);

        }

        return result;

    }

    /**

     * query, because need to manually close the resource, so not recommended

     * for use it

     *

     * @param sql

     * @param args

     * @return ResultSet

     */

    @Deprecated  //注解

    public static ResultSet query(String sql, Object... args) {

        ResultSet result = null;

        Connection con = getconnnection();

        PreparedStatement ps = null;

        try {

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            result = ps.executeQuery();

        } catch (SQLException e) {

            e.printStackTrace();

        }

        return result;

    }

    /**

     * Query a single record

     * 查询单个记录

     * @param sql

     * @param args

     * @return Map<String,Object>

     */

    public static Map<String, Object> queryForMap(String sql, Object... args) {

        Map<String, Object> result = new HashMap<String, Object>();

        List<Map<String, Object>> list = queryForList(sql, args);

        if (list.size() > 0) {

            result = list.get(0);

        }

        return result;

    }

    /**

     * Query a single record

     * 查询单个记录返回强类型对象

     * @param sql

     * @param args

     * @return <T>  //泛型

     */

    public static <T> T queryForObject(String sql, Class<T> clz, Object... args) {

        T result = null;

        List<T> list = queryForList(sql, clz, args);

        if (list.size() > 0) {

            result = list.get(0);

        }

        return result;

    }

    /**

     * Query a single record

     *

     * @param sql

     * @param args

     * @return List<Map<String,Object>>

     */

    public static List<Map<String, Object>> queryForList(String sql, Object... args) {

        List<Map<String, Object>> result = new ArrayList<Map<String, Object>>();

        Connection con = null;

        ResultSet rs = null;

        PreparedStatement ps = null;

        try {

            con = getconnnection();

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            rs = ps.executeQuery();

            ResultSetMetaData rsmd = rs.getMetaData();

            int columnCount = rsmd.getColumnCount();

            while (rs.next()) {

                Map<String, Object> map = new HashMap<String, Object>();

                for (int i = 1; i <= columnCount; i++) {

                    map.put(rsmd.getColumnLabel(i), rs.getObject(i));

                }

                result.add(map);

            }

        } catch (SQLException e) {

            e.printStackTrace();

        } finally {

            close(rs, ps, con);

        }

        return result;

    }

    /**

     * Query records

     * 查询多个对象，返回强类型集合

     * @param sql

     * @param args

     * @return List<T>

     */

    public static <T> List<T> queryForList(String sql, Class<T> clz, Object... args) {

        List<T> result = new ArrayList<T>();

        Connection con = null;

        PreparedStatement ps = null;

        ResultSet rs = null;

        try {

            con = getconnnection();

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            rs = ps.executeQuery();

            ResultSetMetaData rsmd = rs.getMetaData();

            int columnCount = rsmd.getColumnCount();

            while (rs.next()) {

                T obj = clz.newInstance();

                for (int i = 1; i <= columnCount; i++) {

                    String columnName = rsmd.getColumnName(i);

                    String methodName = "set" + columnName.substring(0, 1).toUpperCase()

                            + columnName.substring(1, columnName.length());

                    Method method[] = clz.getMethods();

                    for (Method meth : method) {

                        if (methodName.equals(meth.getName())) {

                            meth.invoke(obj, rs.getObject(i));

                        }

                    }

                }

                result.add(obj);

            }

        } catch (InstantiationException e) {

            e.printStackTrace();

        } catch (IllegalAccessException e) {

            e.printStackTrace();

        } catch (SQLException e) {

            e.printStackTrace();

        } catch (IllegalArgumentException e) {

            e.printStackTrace();

        } catch (InvocationTargetException e) {

            e.printStackTrace();

        } finally {

            close(rs, ps, con);

        }

        return result;

    }

}

5.2、WbDao

package com.dao;

import java.util.List;

import com.weibo.Wb;

/**微博数据访问*/

public class WbDao {

    /**获得所有的微博信息*/

    public List<Wb> all(){

        return JDBCUtils.queryForList("select * from wb;", Wb.class);

    }

    /**添加单条微博信息*/

    public int add(String bt,String nr){

        return JDBCUtils.update("insert into wb(bt,nr) values(?,?);", bt,nr);

    }

}

六、展示微博列表

index.jsp

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

<%@page import="com.weibo.Wb"%>

<%@page import="com.dao.WbDao"%>

<%

//实例化数据访问对象

WbDao dao=new WbDao();

%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

  <head>

    <title>人工智能微博</title>

    <meta http-equiv="pragma" content="no-cache">

    <meta http-equiv="cache-control" content="no-cache">

    <meta http-equiv="expires" content="0">

  </head>

  <body>

     <h2>人工智能微博</h2>

     <ul>

        <%for(Wb obj : dao.all()){ %>

            <li><%=obj.getBt() %> <%=obj.getNr() %></li>

        <%} %>

     </ul>

  </body>

</html>

运行效果：

七、添加新内容

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

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>

  <head>

    <title>人工智能微博</title>

    <meta http-equiv="pragma" content="no-cache">

    <meta http-equiv="cache-control" content="no-cache">

    <meta http-equiv="expires" content="0">

  </head>

  <body>

     <h2>人工智能微博 - 发布</h2>

   <form action="Add"  method="Post">

     <p>

         标题：<input name="bt" />

     </p>

     <p>

         内容：<textarea name="bt"  cols="50"  rows="5"></textarea>

     </p>

     <p>

        <input type="submit" value="保存" />

     </p>

  </form>

  </body>

</html>

效果：

Add Servlet

package com.action;

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.dao.WbDao;

public class Add extends HttpServlet {

    public void doPost(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {

        //设置响应编码为utf-8

        response.setCharacterEncoding("utf-8");

        //设置请求编码为utf-8

        request.setCharacterEncoding("utf-8");

        //实例化数据访问对象

        WbDao dao=new WbDao();

        //执行添加

        dao.add(request.getParameter("bt"), request.getParameter("nr"));

        //转到首页

        response.sendRedirect("index.jsp");

    }

}

八、资料与练习

电子书管理系统(rebot) 120分钟

要求：请使用JavaEE实现一个电子书管理系统，电子书的属性主要包含：标题(title)、页数(page)、类型(category)，系统可以选择人工智能、计算机、文学、神话、自然科学。

1、创建数据库Lib与表book，添加3行以上的数据，导出sql脚本。20分

2、创建动态Java Web项目，添加数据库驱动程序。20分

3、实现电子书展示功能，index.jsp。20分

4、实现电子书添加功能，add.jsp。30分

5、实现展示与添加功能间的跳转。5分

6、代码规范，注释完整，命名合理，分层开发，界面美观。5分

将数据库脚本（导出）、JavaWeb项目、已实现功能的截图、项目截图打包成压缩文件，命名：班级_姓名，如：S2SR136_张三

示例下载：http://files.cnblogs.com/files/best/weibo.zip

九、人工智能微博二

9.1、wz bean

package com.weibo.bean;

/***

 * 文章

 */

public class Wz {

    /** 编号 */

    private int bh;

    /** 标题 */

    private String bt;

    /** 内容 */

    private String nr;

    public int getBh() {

        return bh;

    }

    public void setBh(int bh) {

        this.bh = bh;

    }

    public String getBt() {

        return bt;

    }

    public void setBt(String bt) {

        this.bt = bt;

    }

    public String getNr() {

        return nr;

    }

    public void setNr(String nr) {

        this.nr = nr;

    }

}

9.2、JDBCUtil

package com.weibo.dao;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.ResultSetMetaData;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

public class JDBCUtils {

    public static String DRIVER="com.mysql.jdbc.Driver";

    public static String URL="jdbc:mysql://127.0.0.1:3306/weibo?useUnicode=true&characterEncoding=UTF-8";

    public static String USER_NAME="root";

    public static String PASSWORD="uchr@123";

    //加载驱动

    static {

        try {

            Class.forName(DRIVER);

        } catch (ClassNotFoundException e) {

            e.printStackTrace();

        }

    }

    private JDBCUtils() {

    }

    /**

     * 获得连接

     *

     * @return

     */

    public static Connection getconnnection() {

        Connection con = null;

        try {

            con = DriverManager.getConnection(URL, USER_NAME, PASSWORD);

        } catch (SQLException e) {

            e.printStackTrace();

        }

        return con;

    }

    /**

     * 关闭连接

     *

     * @param rs

     * @param st

     * @param con

     */

    public static void close(ResultSet rs, Statement st, Connection con) {

        try {

            try {

                if (rs != null) {

                    rs.close();

                }

            } finally {

                try {

                    if (st != null) {

                        st.close();

                    }

                } finally {

                    if (con != null)

                        con.close();

                }

            }

        } catch (SQLException e) {

            e.printStackTrace();

        }

    }

    /**

     * 关闭连接

     *

     * @param rs

     */

    public static void close(ResultSet rs) {

        Statement st = null;

        Connection con = null;

        try {

            try {

                if (rs != null) {

                    st = rs.getStatement();

                    rs.close();

                }

            } finally {

                try {

                    if (st != null) {

                        con = st.getConnection();

                        st.close();

                    }

                } finally {

                    if (con != null) {

                        con.close();

                    }

                }

            }

        } catch (SQLException e) {

            e.printStackTrace();

        }

    }

    /**

     * 关闭连接

     *

     * @param st

     * @param con

     */

    public static void close(Statement st, Connection con) {

        try {

            try {

                if (st != null) {

                    st.close();

                }

            } finally {

                if (con != null)

                    con.close();

            }

        } catch (SQLException e) {

            e.printStackTrace();

        }

    }

    /**

     * insert/update/delete

     * 增加/更新/删除

     *

     * @param sql 数据库语句

     * @param args 可变参数（可以不带参数，可以带0-n个参数）

     * @return

     */

    public static int update(String sql, Object... args) {

        int result = 0;

        Connection con = getconnnection();

        PreparedStatement ps = null;

        try {

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            result = ps.executeUpdate();

        } catch (SQLException e) {

            e.printStackTrace();

        } finally {

            close(ps, con);

        }

        return result;

    }

    /**

     * query, because need to manually close the resource, so not recommended

     * for use it

     *

     * @param sql

     * @param args

     * @return ResultSet

     */

    @Deprecated  //注解

    public static ResultSet query(String sql, Object... args) {

        ResultSet result = null;

        Connection con = getconnnection();

        PreparedStatement ps = null;

        try {

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            result = ps.executeQuery();

        } catch (SQLException e) {

            e.printStackTrace();

        }

        return result;

    }

    /**

     * Query a single record

     * 查询单个记录

     * @param sql

     * @param args

     * @return Map<String,Object>

     */

    public static Map<String, Object> queryForMap(String sql, Object... args) {

        Map<String, Object> result = new HashMap<String, Object>();

        List<Map<String, Object>> list = queryForList(sql, args);

        if (list.size() > 0) {

            result = list.get(0);

        }

        return result;

    }

    /**

     * Query a single record

     * 查询单个记录返回强类型对象

     * @param sql

     * @param args

     * @return <T>  //泛型

     */

    public static <T> T queryForObject(String sql, Class<T> clz, Object... args) {

        T result = null;

        List<T> list = queryForList(sql, clz, args);

        if (list.size() > 0) {

            result = list.get(0);

        }

        return result;

    }

    /**

     * Query a single record

     *

     * @param sql

     * @param args

     * @return List<Map<String,Object>>

     */

    public static List<Map<String, Object>> queryForList(String sql, Object... args) {

        List<Map<String, Object>> result = new ArrayList<Map<String, Object>>();

        Connection con = null;

        ResultSet rs = null;

        PreparedStatement ps = null;

        try {

            con = getconnnection();

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            rs = ps.executeQuery();

            ResultSetMetaData rsmd = rs.getMetaData();

            int columnCount = rsmd.getColumnCount();

            while (rs.next()) {

                Map<String, Object> map = new HashMap<String, Object>();

                for (int i = 1; i <= columnCount; i++) {

                    map.put(rsmd.getColumnLabel(i), rs.getObject(i));

                }

                result.add(map);

            }

        } catch (SQLException e) {

            e.printStackTrace();

        } finally {

            close(rs, ps, con);

        }

        return result;

    }

    /**

     * Query records

     * 查询多个对象，返回强类型集合

     * @param sql

     * @param args

     * @return List<T>

     */

    public static <T> List<T> queryForList(String sql, Class<T> clz, Object... args) {

        List<T> result = new ArrayList<T>();

        Connection con = null;

        PreparedStatement ps = null;

        ResultSet rs = null;

        try {

            con = getconnnection();

            ps = con.prepareStatement(sql);

            if (args != null) {

                for (int i = 0; i < args.length; i++) {

                    ps.setObject((i + 1), args[i]);

                }

            }

            rs = ps.executeQuery();

            ResultSetMetaData rsmd = rs.getMetaData();

            int columnCount = rsmd.getColumnCount();

            while (rs.next()) {

                T obj = clz.newInstance();

                for (int i = 1; i <= columnCount; i++) {

                    String columnName = rsmd.getColumnName(i);

                    String methodName = "set" + columnName.substring(0, 1).toUpperCase()

                            + columnName.substring(1, columnName.length());

                    Method method[] = clz.getMethods();

                    for (Method meth : method) {

                        if (methodName.equals(meth.getName())) {

                            meth.invoke(obj, rs.getObject(i));

                        }

                    }

                }

                result.add(obj);

            }

        } catch (InstantiationException e) {

            e.printStackTrace();

        } catch (IllegalAccessException e) {

            e.printStackTrace();

        } catch (SQLException e) {

            e.printStackTrace();

        } catch (IllegalArgumentException e) {

            e.printStackTrace();

        } catch (InvocationTargetException e) {

            e.printStackTrace();

        } finally {

            close(rs, ps, con);

        }

        return result;

    }

}

9.3、WzDao

package com.weibo.dao;

import java.util.List;

import com.weibo.bean.Wz;

/**

 * 文章服务

 * 数据访问

 *

 */

public class WzDao {

    /**获得所有的文章信息*/

    public List<Wz> all(){

        return JDBCUtils.queryForList("select bh,bt,nr from wz", Wz.class);

    }

    /**新增文章*/

    public int add(String bt,String nr){

        return JDBCUtils.update("insert into wz(bt,nr) values(?,?)", bt,nr);

    }

}

9.4、index.jsp页面

<%@page import="com.weibo.bean.Wz"%>

<%@page import="com.weibo.dao.WzDao"%>

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

 <%

 WzDao wzdao=new WzDao();

 %>

<!DOCTYPE html>

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>人工智能微博</title>

</head>

<body>

<h2>人工智能微博</h2>

<ul>

<%for(Wz wz : wzdao.all()) {%>

    <li><%=wz.getBh() %></li>

    <li><%=wz.getBt() %></li>

    <li><%=wz.getNr() %></li>

    <li><a href="Delwz?bh=<%=wz.getBh() %>">删除</a></li>

    <hr/>

<%} %>

</ul>

<a href="add.jsp">发布</a>

</body>

</html>

9.5、add.jsp页面

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

<!DOCTYPE html>

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>人工智能微博 - 发布</title>

</head>

<body>

<h2>人工智能微博 - 发布</h2>

<form action="Addwz" method="post">

  <p>

   标题：<input  type="text" name="bt" />

  </p>

  <p>

   内容：<textarea  type="text" name="nr"   cols="60" rows="6" ></textarea>

  </p>

  <p>

     <input type="submit"  value="提交" />

  </p>

</form>

<a href="index.jsp">列表</a>

</body>

</html>

9.6、Addwz Servlet

package com.weibo.action;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.weibo.dao.WzDao;

/**

 * Servlet implementation class Addwz

 */

@WebServlet("/Addwz")

public class Addwz extends HttpServlet {

    private static final long serialVersionUID = 1L;

    /**

     * @see HttpServlet#HttpServlet()

     */

    public Addwz() {

        super();

        // TODO Auto-generated constructor stub

    }

    /**

     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

     */

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        //设置编码

        request.setCharacterEncoding("utf-8");

        response.setCharacterEncoding("utf-8");

        //获得参数

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

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

        //执行添加到数据库

        WzDao dao=new WzDao();

        dao.add(bt, nr);

        //跳转到指定页面

        response.sendRedirect("index.jsp");

    }

}

9.7、运行结果

列表：

发布：

9.8、删除与样式

index.jsp

<%@page import="com.weibo.bean.Wz"%>

<%@page import="com.weibo.dao.WzDao"%>

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

 <%

 WzDao wzdao=new WzDao();

 %>

<!DOCTYPE html>

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>人工智能微博</title>

<style>

.nr{

    border:1px dashed #666;

    color:#666;

    width:70%;

    line-height:26px;

    margin:8px;

}

.nr:hover{

    color:red;

    box-shadow:5px 5px 3px #999;

    border-radius:10px;

}

</style>

</head>

<body>

<h2>人工智能微博</h2>

<ul>

<%for(Wz wz : wzdao.all()) {%>

    <li><%=wz.getBh() %></li>

    <li><%=wz.getBt() %></li>

    <li class="nr"><%=wz.getNr() %></li>

    <hr/>

<%} %>

</ul>

<table border="1" width="100%">

<tr>

   <th>编号</th>   <th>标题</th>   <th>内容</th>   <th>操作</th>

</tr>

<%for(Wz wz : wzdao.all()) {%>

<tr>

   <td><%=wz.getBh() %></td>

    <td><%=wz.getBt() %></td>

    <td><%=wz.getNr().length()>20?wz.getNr().substring(0,20)+"...":wz.getNr() %></td>

    <td><a href="Del?id=<%=wz.getBh() %>"   onclick="return confirm('您确定要删除吗？');">删除</a></td>

</tr>

<%} %>

</table>

<a href="add.jsp">发布</a>

</body>

</html>

Del Servlet

package com.weibo.action;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.weibo.dao.WzDao;

/**

 * Servlet implementation class Del

 */

@WebServlet("/Del")

public class Del extends HttpServlet {

    private static final long serialVersionUID = 1L;

    /**

     * @see HttpServlet#HttpServlet()

     */

    public Del() {

        super();

        // TODO Auto-generated constructor stub

    }

    /**

     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

     */

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        //取得客户端名为id的参数转成int

        int id=Integer.parseInt(request.getParameter("id"));

        //执行删除

        WzDao dao=new WzDao();

        dao.del(id);

        //跳转到首页

        response.sendRedirect("index.jsp");

    }

}

WzDao.java

package com.weibo.dao;

import java.util.List;

import com.weibo.bean.Wz;

/**

 * 文章服务

 * 数据访问

 *

 */

public class WzDao {

    /**获得所有的文章信息*/

    public List<Wz> all(){

        return JDBCUtils.queryForList("select bh,bt,nr from wz", Wz.class);

    }

    /**新增文章*/

    public int add(String bt,String nr){

        return JDBCUtils.update("insert into wz(bt,nr) values(?,?)", bt,nr);

    }

    /**删除文章*/

    public int del(int bh){

        return JDBCUtils.update("delete from wz where bh=?", bh);

    }

}

运行效果：