JAVAWeb实战(后端篇)

因为前后端代码内容过多,这篇只写后端的代码,前端的在另一篇写

项目实战一:

1.创建数据库,表等数据

创建数据库

create database schedule_system

创建表,并添加内容

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;


-- ----------------------------
-- 创建日程表
-- ----------------------------
DROP TABLE IF EXISTS `sys_schedule`;
CREATE TABLE `sys_schedule`  (
  `sid` int NOT NULL AUTO_INCREMENT,
  `uid` int NULL DEFAULT NULL,
  `title` varchar(20) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL,
  `completed` int(1) NULL DEFAULT NULL,
  PRIMARY KEY (`sid`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic;

-- ----------------------------
-- 插入日程数据
-- ----------------------------

-- ----------------------------
-- 创建用户表
-- ----------------------------
DROP TABLE IF EXISTS `sys_user`;
CREATE TABLE `sys_user`  (
  `uid` int NOT NULL AUTO_INCREMENT,
  `username` varchar(10) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL,
  `user_pwd` varchar(100) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL,
  PRIMARY KEY (`uid`) USING BTREE,
  UNIQUE INDEX `username`(`username`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic;

-- ----------------------------
-- 插入用户数据
-- ----------------------------
INSERT INTO `sys_user` VALUES (1, 'zhangsan', 'e10adc3949ba59abbe56e057f20f883e');
INSERT INTO `sys_user` VALUES (2, 'lisi', 'e10adc3949ba59abbe56e057f20f883e');

SET FOREIGN_KEY_CHECKS = 1;

2.创建项目并导入一些需要的jar包

2.1项目结构

2.2导入依赖

XML 复制代码
 <!--servlet项目所需依赖-->
        <!--
          druid 连接池
          json的一些依赖
          jackson-annotations
          jackson-core
          jackson-databind
          lombok              简化实体类
          mysql-connector     数据库驱动
           jakarta.servlet-api  servlet需要的
          -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.2.23</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.13.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.13.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.13.2</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.34</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.33</version>
        </dependency>
        <dependency>
            <groupId>jakarta.servlet</groupId>
            <artifactId>jakarta.servlet-api</artifactId>
            <version>6.1.0</version>
        </dependency>

2.3创建jdbc.properties文件

XML 复制代码
jdbc.user=root
jdbc.password=123456
jdbc.url=jdbc:mysql:///schedule_system
jdbc.driver=com.mysql.cj.jdbc.Driver

3.创建实体类

因为我数据库两个表名分别叫sys_schedule和sys_user

所以为了方便起见我的实体表为:SysSchedule和SysUser

属性名称要和数据库表的字段名称最好保持一致

如果数据库表字段名称式驼峰式的 比如 sys_id 实体表属性可以设置为 sysId

将下划线后的那个字母设置为大写

SysUser实体类

java 复制代码
/*
* 1 实体类的类名和表格名称应该对应  (对应不是一致)
* 2 实体类的属性名和表格的列名应该对应
* 3 每个属性都必须是私有的
* 4 每个属性都应该具备 getter setter
* 5 必须具备无参构造器
* 6 应该实现序列化接口( 缓存  分布式项目数据传递 可能会将对象序列化 )
* 7 应该重写类的hashcode和equals方法
* 8 toString是否重写都可以
*
*
* 使用lombok帮助我们生成这些内容 getter setter  全参构造 无参构造 equals  hashcode
*   lombok使用步骤
*       1 检查idea是否已经安装了lombok插件
*       2 检查是否勾选了 enable  annotation processing
*       3 导入lombok的依赖
*
*
* */

@AllArgsConstructor // 添加了全参构造
@NoArgsConstructor  // 添加了无参构造
@Data //getter setter   equals  hashcode toString
public class SysUser implements Serializable {
    private Integer uid;
    private String username;
    private String userPwd;

}

SysSchedule实体类

java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class SysSchedule implements Serializable {
    private Integer sid;
    private Integer uid;
    private  String title;
    private Integer completed;
}

4.创建全局统一json响应格式

4.1 创建一个枚举类(里面设置一些响应码和响应消息)

java 复制代码
public enum ResultCodeEnum {
    SUCCESS(200,"success"),
    USERNAEM_ERROR(501,"usernameError"),
    PASSWORD_ERROR(503,"passwordError"),
    NOTLOGIN(504,"notlogin"),
    USERNAME_USED(505,"usernameUsed");



    private Integer code;
    private String message;
    private ResultCodeEnum(Integer code ,String message){
        this.code= code;
        this.message = message;

    }

    public Integer getCode() {
        return code;
    }

    public String getMessage() {
        return message;
    }
}

4.2创建全局统一json响应格式类

java 复制代码
package org.example.common;

//全局统一响应的JSON格式处理类
public class Result <T>{   //因为不确定返回消息是什么类型 ,所以这里声明了<T>
    // 返回码
    private Integer code;
    // 返回消息
    private String message;
    // 返回数据
    private T data;
    public Result(){}
    // 返回数据
    protected static <T> Result<T> build(T data) {   //将data添加进去
        Result<T> result = new Result<T>();
        if (data != null)
            result.setData(data);
        return result;            //返回一个result对象
    }
    public static <T> Result<T> build(T body, Integer code, String message) { //
        Result<T> result = build(body);  // 创建一个result对象,并添加data对象
        result.setCode(code);
        result.setMessage(message);
        return result;
    }
    public static <T> Result<T> build(T body, ResultCodeEnum resultCodeEnum) {
        Result<T> result = build(body);       //创建result对象并添加data数据
        result.setCode(resultCodeEnum.getCode());  //给响应码添加枚举类中的数据
        result.setMessage(resultCodeEnum.getMessage()); //给响应消息添加枚举类中的数据
        return result;
    }
    /**
     * 操作成功
     * @param data  baseCategory1List
     * @param <T>
     * @return
     */
    public static<T> Result<T> ok(T data){          //返回一个result对象,这是一个操作成功的数据,如果操作成功就执行它
        Result<T> result = build(data);    //创建result对象并添加data数据
        return build(data, ResultCodeEnum.SUCCESS); //调用上面的方法,将枚举类中的ResultCodeEnum.SUCCESS赋值给响应码和响应消息并返回result
    }
    public Result<T> message(String msg){          
        this.setMessage(msg);
        return this;
    }
    public Result<T> code(Integer code){     
        this.setCode(code);
        return this;
    }
    public Integer getCode() {
        return code;
    }
    public void setCode(Integer code) {
        this.code = code;
    }
    public String getMessage() {
        return message;
    }
    public void setMessage(String message) {
        this.message = message;
    }
    public T getData() {
        return data;
    }
    public void setData(T data) {
        this.data = data;
    }
}

5.设置一些工具类

5.1MD5加密(固定格式需要的时候复制一下)

java 复制代码
public class MD5Util {
    public static String encrypt(String strSrc) {
        try {
            char hexChars[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8',
                    '9', 'a', 'b', 'c', 'd', 'e', 'f' };
            byte[] bytes = strSrc.getBytes();  //使用平台的默认字符集将此 String 编码为 byte 序列,并 将结果存储到一个新的 byte 数组中。
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(bytes);
            bytes = md.digest();
            int j = bytes.length;
            char[] chars = new char[j * 2];
            int k = 0;
            for (int i = 0; i < bytes.length; i++) {
                byte b = bytes[i];
                chars[k++] = hexChars[b >>> 4 & 0xf];
                chars[k++] = hexChars[b & 0xf];
            }
            return new String(chars);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            throw new RuntimeException("MD5加密出错");
        }

    }

}

5.2 创建导入jdbc.properties和生成Connection对象的工具类(需要的时候复制就可以)

java 复制代码
package org.example.util;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

public class JDBCUtil {
    private static ThreadLocal<Connection> threadLocal =new ThreadLocal<>();
    private static DataSource dataSource;
    // 初始化连接池
    static{
        // 可以帮助我们读取.properties配置文件
        Properties properties =new Properties();
        InputStream resourceAsStream = JDBCUtil.class.getClassLoader().getResourceAsStream("jdbc.properties");
        try {
            properties.load(resourceAsStream);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        try {
            dataSource = DruidDataSourceFactory.createDataSource(properties);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }


    }
    /*1 向外提供连接池的方法*/
    public static DataSource getDataSource(){
        return dataSource;
    }

    /*2 向外提供连接的方法*/
    public static Connection getConnection(){
        Connection connection = threadLocal.get();
        if (null == connection) {
            try {
                connection = dataSource.getConnection();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            threadLocal.set(connection);
        }

        return connection;
    }


    /*定义一个归还连接的方法 (解除和ThreadLocal之间的关联关系) */
    public static void releaseConnection(){
        Connection connection = threadLocal.get();
        if (null != connection) {
            threadLocal.remove();
            // 把连接设置回自动提交的连接
            try {
                connection.setAutoCommit(true);
                // 自动归还到连接池
                connection.close();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
        }
    }
}

5.3创建WEBUtil工具类(需要的时候复制就可以,用来转化json和将json响应出去的)

java 复制代码
package org.example.util;

import com.fasterxml.jackson.databind.ObjectMapper;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.example.common.Result;

import java.io.BufferedReader;
import java.io.IOException;
import java.text.SimpleDateFormat;

public class WebUtil {
    private static ObjectMapper objectMapper;
    // 初始化objectMapper
    static{
        objectMapper=new ObjectMapper();
        // 设置JSON和Object转换时的时间日期格式
        objectMapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
    }
    // 从请求中获取JSON串并转换为Object
    public static <T> T readJson(HttpServletRequest request, Class<T> clazz){
        T t =null;
        BufferedReader reader = null;
        try {
            reader = request.getReader();
            StringBuffer buffer =new StringBuffer();
            String line =null;
            while((line = reader.readLine())!= null){
                buffer.append(line);
            }

            t= objectMapper.readValue(buffer.toString(),clazz);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return t;
    }
    // 将Result对象转换成JSON串并放入响应对象
    public static void writeJson(HttpServletResponse response, Result result){
        response.setContentType("application/json;charset=UTF-8");
        try {
            String json = objectMapper.writeValueAsString(result);
            response.getWriter().write(json);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}

5.4创建一个统一对数据增删改查的工具类(需要的时候复制粘贴)

java 复制代码
package org.example.dao;

import org.example.util.JDBCUtil;

import java.lang.reflect.Field;
import java.sql.*;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.List;

public class BaseDao {
    public <T> T baseQueryObject(Class<T> clazz, String sql, Object ... args) {
        T t = null;
        Connection connection = JDBCUtil.getConnection();
        PreparedStatement preparedStatement = null;
        ResultSet resultSet = null;
        int rows = 0;
        try {
            // 准备语句对象
            preparedStatement = connection.prepareStatement(sql);
            // 设置语句上的参数
            for (int i = 0; i < args.length; i++) {
                preparedStatement.setObject(i + 1, args[i]);
            }

            // 执行 查询
            resultSet = preparedStatement.executeQuery();
            if (resultSet.next()) {
                t = (T) resultSet.getObject(1);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (null != resultSet) {
                try {
                    resultSet.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            if (null != preparedStatement) {
                try {
                    preparedStatement.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }

            }
            JDBCUtil.releaseConnection();
        }
        return t;
    }
    // 公共的查询方法  返回的是对象的集合

    public <T> List<T> baseQuery(Class clazz, String sql, Object ... args){
        List<T> list =new ArrayList<>();
        Connection connection = JDBCUtil.getConnection();
        PreparedStatement preparedStatement=null;
        ResultSet resultSet =null;
        int rows = 0;
        try {
            // 准备语句对象
            preparedStatement = connection.prepareStatement(sql);
            // 设置语句上的参数
            for (int i = 0; i < args.length; i++) {
                preparedStatement.setObject(i+1,args[i]);
            }

            // 执行 查询
            resultSet = preparedStatement.executeQuery();

            ResultSetMetaData metaData = resultSet.getMetaData();
            int columnCount = metaData.getColumnCount();

            // 将结果集通过反射封装成实体类对象
            while (resultSet.next()) {
                // 使用反射实例化对象
                Object obj =clazz.getDeclaredConstructor().newInstance();

                for (int i = 1; i <= columnCount; i++) {
                    String columnName = metaData.getColumnLabel(i);
                    Object value = resultSet.getObject(columnName);
                    // 处理datetime类型字段和java.util.Data转换问题
                    if(value.getClass().equals(LocalDateTime.class)){
                        value= Timestamp.valueOf((LocalDateTime) value);
                    }
                    Field field = clazz.getDeclaredField(columnName);
                    field.setAccessible(true);
                    field.set(obj,value);
                }

                list.add((T)obj);
            }

        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (null !=resultSet) {
                try {
                    resultSet.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
            if (null != preparedStatement) {
                try {
                    preparedStatement.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
            JDBCUtil.releaseConnection();
        }
        return list;
    }

    // 通用的增删改方法
    public int baseUpdate(String sql,Object ... args) {
        // 获取连接
        Connection connection = JDBCUtil.getConnection();
        PreparedStatement preparedStatement=null;
        int rows = 0;
        try {
            // 准备语句对象
            preparedStatement = connection.prepareStatement(sql);
            // 设置语句上的参数
            for (int i = 0; i < args.length; i++) {
                preparedStatement.setObject(i+1,args[i]);
            }

            // 执行 增删改 executeUpdate
            rows = preparedStatement.executeUpdate();
            // 释放资源(可选)


        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            if (null != preparedStatement) {
                try {
                    preparedStatement.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }

            }
            JDBCUtil.releaseConnection();
        }
        // 返回的是影响数据库记录数
        return rows;
    }
}

6.创建跨域过滤器和登入过滤器

6.1跨域过滤器(需要的时候复制)

未来我们使用框架,फ接用一个@CrossOrigin 就可以解决跨ֿ域了。

java 复制代码
package org.example.filter;

import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

import java.io.IOException;

@WebFilter("/*")
public class CrosFilter implements Filter {

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        System.out.println(request.getMethod());
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT,OPTIONS, DELETE, HEAD");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers", "access-control-allow-origin, authority, content-type, version-info, X-Requested-With");
        // 非预检请求,放行即可,预检请求,则到此结束,不需要放行
        if(!request.getMethod().equalsIgnoreCase("OPTIONS")){
            filterChain.doFilter(servletRequest, servletResponse);
        }
    }
}

6.2登入过滤器

没有登入的话不允许访问其他网页,直接重定向到登入界面。

登入成功才可以访问其他网页

java 复制代码
public class LoginFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        // 参数父转子
        HttpServletRequest request =(HttpServletRequest)  servletRequest;
        HttpServletResponse response  =(HttpServletResponse) servletResponse;
        // 获得session域对象
        HttpSession session = request.getSession();
        // 从session域中获得登录的用户对象
        SysUser sysUser = (SysUser)session.getAttribute("sysUser");
        // 判断用户对象是否为空
        if(null == sysUser){
            // 没登录 到login.html
            response.sendRedirect("/login.html");
        }else{
            // 登录过 放行
            filterChain.doFilter(request,response);
        }
    }
}

7.三层架构(service,dao,servlet)

7.0创建全局处理servlet类(重点)

java 复制代码
//全局处理servlet
public class BaseContoller extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String requestURI = req.getRequestURI(); // /schedule/add
        String[] split = requestURI.split("/");
        String methodName = split[split.length-1];
        // 使用 反射 通过方法名获取下面的方法
        Class aClass = this.getClass();
        // 获取方法
        try {
            Method declaredMethod = aClass.getDeclaredMethod(methodName, HttpServletRequest.class, HttpServletResponse.class);

            //暴力 破解方法的访问修饰符的限制
            declaredMethod.setAccessible(true);

            // 执行方法
            declaredMethod.invoke(this,req,resp);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

7.1.1 SysUser dao层

SysUserdao 接口

java 复制代码
public interface SysUserDao {
    /**
     * 向数据库中增加一条用户记录的方法
     * @param sysUser 要增加的记录的username和user_pwd字段以SysUser实体类对象的形式接收
     * @return 增加成功返回1 增加失败返回0
     */
    int addSysUser(SysUser sysUser);

    /**
     * 根据用户名获得完整用户信息的方法
     * @param username 要查询的用户名
     * @return 如果找到了返回SysUser对象,找不到返回null
     */
    SysUser findByUsername(String username);
}

实现类

这里实现了SysUserdao接口,并且还继承了BaseDao工具类,所以可以直接使用它的方法

java 复制代码
public class SysUserDaoImpl extends BaseDao implements SysUserDao {


    //注册账户
    @Override
    public int addSysUser(SysUser sysUser) {
        String sql ="insert into sys_user values(DEFAULT,?,?)";
        return baseUpdate(sql,sysUser.getUsername(),sysUser.getUserPwd());
    }

    //验证账户是否已被占用,登入账户,两个功能
    @Override
    public SysUser findByUsername(String username) {
        String sql ="select uid,username,user_pwd userPwd from sys_user where username = ?";
        List<SysUser> sysUserList = baseQuery(SysUser.class, sql, username);
        return sysUserList!= null && sysUserList.size()>0? sysUserList.get(0): null ;
    }
}

7.1.2service层

SysUserService接口

java 复制代码
public interface SysUserService {

    /**
     * 注册用户的方法
     * @param sysUser 要注册的用户名和明文密码以SysUser对象的形式接收
     * @return 注册成功返回1 注册失败返回0
     */
    int regist(SysUser sysUser);

    /**
     * 根据用户名获得完整用户信息的方法
     * @param username 要查询的用户名
     * @return 如果找到了返回SysUser对象,找不到返回null
     */
    SysUser findByUsername(String username);
}

SysUserService接口实现类

java 复制代码
public class SysUserServiceImpl implements SysUserService {
    private SysUserDao userDao =new SysUserDaoImpl();
    @Override
    public int regist(SysUser sysUser) {

        // 将用户的明文密码转换为密文密码
        sysUser.setUserPwd(MD5Util.encrypt(sysUser.getUserPwd()));
        // 调用DAO 层的方法  将sysUser信息存入数据库
        return userDao.addSysUser(sysUser);
    }

    @Override
    public SysUser findByUsername(String username) {
        return userDao.findByUsername(username);
    }
}

7.1.3servlet层

java 复制代码
package org.example.servlet;

import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import org.example.common.Result;
import org.example.common.ResultCodeEnum;
import org.example.pojo.SysUser;
import org.example.service.SysUserService;
import org.example.service.imp.SysUserServiceImpl;
import org.example.util.MD5Util;
import org.example.util.WebUtil;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

@WebServlet("/user/*")
public class SysUserController  extends BaseContoller {

    private SysUserService userService = new SysUserServiceImpl();



    /**
     * 注册时,接收要注册的用户名,校验用户名是否被占用的业务接口
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    //注册的时候,看当前用户名是否被占用
    protected void checkUsernameUsed(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收用户名
        String username = req.getParameter("username");

        // 调用服务层业务处理方法查询该用于名是否有对应的用户
        SysUser sysUser = userService.findByUsername(username);
        // 如果有 响应 已占用
        // 如果没有 响应 可用

        Result result = Result.ok(null);

        if (null != sysUser) {
            result = Result.build(null, ResultCodeEnum.USERNAME_USED);
        }
        // 将result对象转换为JSON串响应给客户端
        WebUtil.writeJson(resp, result);
    }

    /**
     * 接收用登录请求,完成的登录业务接口
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    //登入
    protected void login(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1 接收用户名和密码
        SysUser sysUser = WebUtil.readJson(req, SysUser.class);
        //2 调用服务层方法,根据用户名查询用户信息
        SysUser loginUser = userService.findByUsername(sysUser.getUsername());

        Result result = null;

        if (null == loginUser) {
            result = Result.build(null, ResultCodeEnum.USERNAEM_ERROR);

        } else if (!MD5Util.encrypt(sysUser.getUserPwd()).equals(loginUser.getUserPwd())) {
            result = Result.build(null, ResultCodeEnum.PASSWORD_ERROR);
        } else {
            // 登录程序,将用户uid和username响应给客户端
            Map data = new HashMap();
            loginUser.setUserPwd("");
            data.put("loginUser", loginUser);
            result = Result.ok(data);
        }
        // 3将登录结果响应给客户端
        WebUtil.writeJson(resp, result);

    }

    /**
     * 接收用户注册请求的业务处理方法( 业务接口 不是java中的interface  )
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    //注册
    protected void regist(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 1 接收客户端提交的json参数,并转换为User对象,获取信息
        SysUser registUer = WebUtil.readJson(req, SysUser.class);

        // 2 调用服务层方法,完成注册功能
        //将参数放入一个SysUser对象中,在调用regist方法时传入
        int rows = userService.regist(registUer);
        // 3 根据注册结果(成功  失败) 做页面跳转
        Result result = Result.ok(null);
        if (rows < 1) {
            result = Result.build(null, ResultCodeEnum.USERNAME_USED);
        }
        WebUtil.writeJson(resp, result);
    }
}

7.2.1 SysSchedule dao层

SysScheduleDao接口

java 复制代码
public interface SysScheduleDao {
    /**
     * 用于向数据中增加一条日程记录
     * @param schedule 日程数据以SysSchedule实体类对象形式入参
     * @return 返回影响数据库记录的行数, 行数为0说明增加失败,行数大于0说明增加成功
     */
    int addSchedule(SysSchedule schedule);


    /**
     * 查询所有用户的所有日程
     * @return 将所有日程放入一个:List<SysSchedule>集合中返回
     */
    List<SysSchedule> findAll();

    List<SysSchedule> findItemListByUid(int uid);

    Integer addDefault(int uid);

    Integer updateSchedule(SysSchedule schedule);

    Integer removeSchedule(int sid);
}

对应的实现类

java 复制代码
public class SysScheduleDaoImpl extends BaseDao implements SysScheduleDao {
    @Override
    public int addSchedule(SysSchedule schedule) {
        String sql ="insert into sys_schedule values(DEFAULT,?,?,?)";
        int rows = baseUpdate(sql,schedule.getUid(),schedule.getTitle(),schedule.getCompleted());
        return rows;
    }

    @Override
    public List<SysSchedule> findAll() {
        String sql ="select sid,uid,title,completed from sys_schedule";
        List<SysSchedule> scheduleList = baseQuery(SysSchedule.class, sql);
        return scheduleList;
    }

    @Override
    public List<SysSchedule> findItemListByUid(int uid) {
        String sql = "select sid ,uid,title,completed from sys_schedule where uid = ? ";
        List<SysSchedule> itemList = baseQuery(SysSchedule.class, sql, uid);
        return itemList;
    }

    @Override
    public Integer addDefault(int uid) {
        String sql = "insert into sys_schedule values (DEFAULT,?,'请输入日程',0) ";
        return baseUpdate(sql,uid);
    }

    @Override
    public Integer updateSchedule(SysSchedule schedule) {
        String sql ="update sys_schedule set title = ? ,completed = ?  where  sid = ?";
        return baseUpdate(sql,schedule.getTitle(),schedule.getCompleted(),schedule.getSid());
    }

    @Override
    public Integer removeSchedule(int sid) {
        String sql = "delete from sys_schedule where sid = ?";
        return baseUpdate(sql,sid);
    }
}

7.2.2service层

接口

java 复制代码
public interface SysScheduleService {
    List<SysSchedule> findItemListByUid(int uid);

    Integer addDefault(int uid);

    Integer updateSchedule(SysSchedule schedule);

    Integer removeSchedul(int sid);
}

实现类

java 复制代码
public class SysScheduleServiceImpl implements SysScheduleService {
    private SysScheduleDao scheduleDao =new SysScheduleDaoImpl();

    @Override
    public List<SysSchedule> findItemListByUid(int uid) {
        return scheduleDao.findItemListByUid(uid);
    }

    @Override
    public Integer addDefault(int uid) {
        return scheduleDao.addDefault(uid);
    }

    @Override
    public Integer updateSchedule(SysSchedule schedule) {
        return scheduleDao.updateSchedule(schedule);
    }

    @Override
    public Integer removeSchedul(int sid) {
        return scheduleDao.removeSchedule(sid);
    }
}

7.2.3servlet层

java 复制代码
@WebServlet( "/schedule/*")
public class SysScheduleController extends BaseContoller {
    private SysScheduleService scheduleService =new SysScheduleServiceImpl();

    protected void removeSchedule(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        int sid = Integer.parseInt(req.getParameter("sid"));
        // 调用服务层方法 删除数据
        scheduleService.removeSchedul(sid);
        // 响应  成功信息

        WebUtil.writeJson(resp, Result.ok(null));



    }

    protected void updateSchedule(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收请求体中的JSON串 转换成一个SysSchedule
        SysSchedule schedule = WebUtil.readJson(req, SysSchedule.class);
        // 调用服务层方法,将信息更新进入数据
        scheduleService.updateSchedule(schedule);

        WebUtil.writeJson(resp,Result.ok(null));



    }

    protected void addDefaultSchedule(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收请求中的uid参数
        int uid =Integer.parseInt(req.getParameter("uid"));
        // 调用服务层方法,向数据库中 增加一条 空记录
        scheduleService.addDefault(uid);

        WebUtil.writeJson(resp,Result.ok(null));
    }

    protected void findAllSchedule(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收请求中的uid参数
        int uid =Integer.parseInt(req.getParameter("uid"));

        // 查询用户的所有日程
        List<SysSchedule> itemList =scheduleService.findItemListByUid(uid);

        // 将用户的所有日程放入一个Result对象
        Map data =new HashMap();
        data.put("itemList",itemList);

        Result result = Result.ok(data);
        // 将Result对象转换为json响应给客户端
        WebUtil.writeJson(resp,result);
    }
}

项目实战一结束

项目实战二

全局json统一返回类省略

枚举类省略

MD5工具类省略

jdbc需要的两个工具类省略(一个引入properties和创建Conn对象的类,一个增删改查的类)

跨域过滤器省略

Webutil省略

全局处理servlet类省略

需要的jar包和上面的的一样

jdbc..properties文件省略

以上参考上一个项目,可直接复制粘贴,这里就不展示了

在上面那个的基础上,新增两个jar包,用于token

XML 复制代码
     <!--token-->
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.3.0</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.9.1</version>
        </dependency>

1.创建数据库,表等操作

1.1创建数据库

create database top_news

1.2创建数据库表,并添加数据

DROP TABLE IF EXISTS `news_headline`;
CREATE TABLE `news_headline`  (
  `hid` int NOT NULL AUTO_INCREMENT COMMENT '头条id',
  `title` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '头条标题',
  `article` varchar(5000) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '头条新闻内容',
  `type` int NOT NULL COMMENT '头条类型id',
  `publisher` int NOT NULL COMMENT '头条发布用户id',
  `page_views` int NOT NULL COMMENT '头条浏览量',
  `create_time` datetime(0) NULL DEFAULT NULL COMMENT '头条发布时间',
  `update_time` datetime(0) NULL DEFAULT NULL COMMENT '头条最后的修改时间',
  `is_deleted` int NULL DEFAULT NULL COMMENT '头条是否被删除 1 删除  0 未删除',
  PRIMARY KEY (`hid`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = DYNAMIC;

-- ----------------------------
-- Records of news_headline
-- ----------------------------
INSERT INTO `news_headline` VALUES (1, 'aaasd', 1, 1, 0, '2023-06-25 09:26:20', '2023-06-25 09:26:20', 0);
INSERT INTO `news_headline` VALUES (2, 'bbbb', 1, 1, 0, '2023-06-25 09:28:06', '2023-06-25 09:28:06', 0);
INSERT INTO `news_headline` VALUES (3, 'ccc。', 1, 1, 0, '2023-06-25 09:31:00', '2023-06-25 09:31:00', 0);
INSERT INTO `news_headline` VALUES (4, 'ddd', 1, 1, 0, '2023-06-25 09:31:36', '2023-06-25 09:31:36', 0);

-- ----------------------------
-- Table structure for news_type
-- ----------------------------
DROP TABLE IF EXISTS `news_type`;
CREATE TABLE `news_type`  (
  `tid` int NOT NULL AUTO_INCREMENT COMMENT '新闻类型id',
  `tname` varchar(10) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '新闻类型描述',
  PRIMARY KEY (`tid`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 8 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = DYNAMIC;

-- ----------------------------
-- Records of news_type
-- ----------------------------
INSERT INTO `news_type` VALUES (1, '新闻');
INSERT INTO `news_type` VALUES (2, '体育');
INSERT INTO `news_type` VALUES (3, '娱乐');
INSERT INTO `news_type` VALUES (4, '科技');
INSERT INTO `news_type` VALUES (5, '其他');

-- ----------------------------
-- Table structure for news_user
-- ----------------------------
DROP TABLE IF EXISTS `news_user`;
CREATE TABLE `news_user`  (
  `uid` int NOT NULL AUTO_INCREMENT COMMENT '用户id',
  `username` varchar(20) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '用户登录名',
  `user_pwd` varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '用户登录密码密文',
  `nick_name` varchar(20) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '用户昵称',
  PRIMARY KEY (`uid`) USING BTREE,
  UNIQUE INDEX `username_unique`(`username`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 9 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = DYNAMIC;

-- ----------------------------
-- Records of news_user
-- ----------------------------
INSERT INTO `news_user` VALUES (1, 'zhangsan', 'e10adc3949ba59abbe56e057f20f883e', '张三');
INSERT INTO `news_user` VALUES (2, 'lisi', 'e10adc3949ba59abbe56e057f20f883e', '李四');
INSERT INTO `news_user` VALUES (5, 'zhangxiaoming', 'e10adc3949ba59abbe56e057f20f883e', '张小明');
INSERT INTO `news_user` VALUES (6, 'xiaohei', 'e10adc3949ba59abbe56e057f20f883e', '李小黑');

SET FOREIGN_KEY_CHECKS = 1;
update news_headline set create_time=now() ,update_time=now()

2.创建JwtHelperٖ工具类

java 复制代码
package org.example.util;

import com.alibaba.druid.util.StringUtils;
import io.jsonwebtoken.*;

import java.util.Date;

public class JwtHelper {
    private static long tokenExpiration = 24*60*60*1000;
    private static String tokenSignKey = "123456";

    //生成token字符串
    public static String createToken(Long userId) {
        String token = Jwts.builder()

                .setSubject("YYGH-USER")
                .setExpiration(new Date(System.currentTimeMillis() + tokenExpiration))
                .claim("userId", userId)
                .signWith(SignatureAlgorithm.HS512, tokenSignKey)
                .compressWith(CompressionCodecs.GZIP)
                .compact();
        return token;
    }

    //从token字符串获取userid
    public static Long getUserId(String token) {
        if(StringUtils.isEmpty(token)) return null;
        Jws<Claims> claimsJws = Jwts.parser().setSigningKey(tokenSignKey).parseClaimsJws(token);
        Claims claims = claimsJws.getBody();
        Integer userId = (Integer)claims.get("userId");
        return userId.longValue();
    }



    //判断token是否有效
    public static boolean isExpiration(String token){
        try {
            boolean isExpire = Jwts.parser()
                    .setSigningKey(tokenSignKey)
                    .parseClaimsJws(token)
                    .getBody()
                    .getExpiration().before(new Date());
            //没有过期,有效,返回false
            return isExpire;
        }catch(Exception e) {
            //过期出现异常,返回true
            return true;
        }
    }
}

3.创建实体类与它的vo

3.1实体类

复制代码
NewsHeadline
java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class NewsHeadline implements Serializable {
    private Integer hid;
    private String title;
    private String article;
    private Integer type;
    private Integer publisher;
    private Integer pageViews;
    private Date createTime;
    private Date updateTime;
    private Integer isDeleted;

}
复制代码
NewsType
java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class NewsType implements Serializable {
    private Integer tid;
    private String tname;
}
复制代码
NewsUser
java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class NewsUser implements Serializable {
    private Integer uid;
    private String username;
    private String userPwd;
    private String nickName;
}

3.2 vo类

复制代码
HeadlineDetailVo
java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class HeadlineDetailVo implements Serializable {
    private Integer hid;
    private String title;
    private String article;
    private Integer type;
    private String typeName;
    private Integer pageViews;
    private Long pastHours;
    private Integer publisher;
    private String author;
}
复制代码
HeadlinePageVo
java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class HeadlinePageVo implements Serializable {
    private Integer hid;
    private String title;
    private Integer type;
    private Integer pageViews;
    private Long pastHours;
    private Integer publisher;
}
复制代码
HeadlineQueryVo
java 复制代码
@AllArgsConstructor
@NoArgsConstructor
@Data
public class HeadlineQueryVo implements Serializable {
    private String keyWords;
    private Integer type ;
    private Integer pageNum;
    private Integer pageSize;
}

4.登入过滤器

java 复制代码
@WebFilter("/headline/*")

public class LoginFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request =(HttpServletRequest) servletRequest;
        HttpServletResponse response =(HttpServletResponse) servletResponse;
        String token = request.getHeader("token");

        boolean flag = null != token && (!JwtHelper.isExpiration(token));

        if(flag){
            filterChain.doFilter(servletRequest,servletResponse);
        }else{
            WebUtil.writeJson(response, Result.build(null, ResultCodeEnum.NOTLOGIN));
        }
    }
}

5.三层架构

dao层

复制代码
NewsHeadlineDao接口
java 复制代码
public interface NewsHeadlineDao {
    /**
     *
     * @param headlineQueryVo
     * @return
     */
    List<HeadlinePageVo> findPageList(HeadlineQueryVo headlineQueryVo);

    /**
     *
     * @param headlineQueryVo
     * @return
     */
    int findPageCount(HeadlineQueryVo headlineQueryVo);

    /**
     *
     * @param hid
     * @return
     */
    int incrPageViews(int hid);

    /**
     *
     * @param hid
     * @return
     */
    HeadlineDetailVo findHealineDetail(int hid);

    int addNewsHeadline(NewsHeadline newsHeadline);

    /**
     *
     * @param hid
     * @return
     */
    NewsHeadline findByHid(Integer hid);

    int update(NewsHeadline newsHeadline);

    int removeByHid(int hid);
}
复制代码
NewsTypeDao接口
java 复制代码
public interface NewsTypeDao {
    /**
     *
     * @return
     */
    List<NewsType> findAll();
}
复制代码
NewsUserDao接口
java 复制代码
public interface NewsUserDao {
    /**
     *
     * @param username
     * @return
     */
    NewsUser findByUsername(String username);

    /**
     *
     * @param userId
     * @return
     */
    NewsUser findByUid(Integer userId);

    /**
     *
     * @param registUser
     * @return
     */
    Integer insertUser(NewsUser registUser);
}
复制代码
NewsHeadlineDaoImpl实现类
java 复制代码
public class NewsHeadlineDaoImpl extends BaseDao implements NewsHeadlineDao {

    /*
    *
    *       private Integer hid;
            private String title;
            private Integer type;
            private Integer pageViews;
            private Long pastHours;
            private Integer publisher;
            *
            *
            *
            *       private String keyWords;
                    private Integer type ;
                    private Integer pageNum;
                    private Integer pageSize;
            *
            * */
    @Override
    public List<HeadlinePageVo> findPageList(HeadlineQueryVo headlineQueryVo) {
        List params = new ArrayList();

        String sql  = """
                select 
                    hid ,
                    title,
                    type,
                    page_views pageViews,
                    TIMESTAMPDIFF(HOUR,create_time,now()) pastHours ,
                    publisher 
                from 
                    news_headline
                where 
                    is_deleted = 0
                    
                """;
        if (headlineQueryVo.getType() != 0 ){
            sql = sql.concat(" and type = ? ");
            params.add(headlineQueryVo.getType());

        }
        if(headlineQueryVo.getKeyWords() != null && !headlineQueryVo.getKeyWords().equals("")){
            sql = sql.concat(" and title like ? ");
            params.add("%"+headlineQueryVo.getKeyWords()+"%");
        }

        sql=sql.concat(" order by pastHours ASC , page_views DESC ");
        sql=sql.concat(" limit ? , ? ");
        params.add((headlineQueryVo.getPageNum()-1)*headlineQueryVo.getPageSize());
        params.add(headlineQueryVo.getPageSize());

        return baseQuery(HeadlinePageVo.class,sql,params.toArray());
    }

    @Override
    public int findPageCount(HeadlineQueryVo headlineQueryVo) {
        List params = new ArrayList();

        String sql  = """
                select 
                    count(1)
                from 
                    news_headline
                where 
                    is_deleted = 0
                    
                """;
        if (headlineQueryVo.getType() != 0 ){
            sql = sql.concat(" and type = ? ");
            params.add(headlineQueryVo.getType());

        }
        if(headlineQueryVo.getKeyWords() != null && !headlineQueryVo.getKeyWords().equals("")){
            sql = sql.concat(" and title like ? ");
            params.add("%"+headlineQueryVo.getKeyWords()+"%");
        }

        Long count = baseQueryObject(Long.class, sql, params.toArray());
        return count.intValue();
    }

    @Override
    public int incrPageViews(int hid) {
        String sql ="update  news_headline set page_views = page_views + 1 where hid = ?";

        return baseUpdate(sql,hid);
    }



    @Override
    public HeadlineDetailVo findHealineDetail(int hid) {
        String sql = """
                select
                  h.hid hid ,
                  h.title title ,
                  h.article article ,
                  h.type type ,
                  t.tname typeName ,
                  h.page_views pageViews ,
                  TIMESTAMPDIFF(HOUR,h.create_time,now() )pastHours ,
                  h.publisher publisher ,
                  u.nick_name author 
                from 
                    news_headline h
                left join 
                    news_type  t
                on  
                    h.type = t.tid
                left join
                    news_user u
                on
                    h.publisher = u.uid
                where 
                    h.hid = ?
                """;
        List<HeadlineDetailVo> list = baseQuery(HeadlineDetailVo.class, sql, hid);

        return null != list && list.size()>0 ?  list.get(0):null;
    }

    @Override
    public int addNewsHeadline(NewsHeadline newsHeadline) {
        String sql = """
                insert into news_headline 
                values (DEFAULT,?,?,?,?,0,now(),now(),0)
                """;
        return baseUpdate(sql,
                newsHeadline.getTitle(),
                newsHeadline.getArticle(),
                newsHeadline.getType(),
                newsHeadline.getPublisher()
                );
    }

    @Override
    public NewsHeadline findByHid(Integer hid) {
        String sql = """
                select
                    hid,
                    title,
                    article,
                    type,
                    publisher,
                    page_views pageViews,
                    create_time createTime,
                    update_time updateTime,
                    is_deleted isDeleted
                from 
                    news_headline
                where 
                    hid = ?
                """;
        List<NewsHeadline> list = baseQuery(NewsHeadline.class, sql, hid);
        return null != list && list.size()>0?list.get(0):null;
    }


    @Override
    public int update(NewsHeadline newsHeadline) {
        String sql = """
                update 
                    news_headline
                set
                    title = ?,
                    article = ?,
                    type = ?,
                    update_time = now()
                where 
                    hid = ?     
                """;
        return baseUpdate(sql,
                newsHeadline.getTitle(),
                newsHeadline.getArticle(),
                newsHeadline.getType(),
                newsHeadline.getHid()
                );
    }


    @Override
    public int removeByHid(int hid) {
        String sql = "update news_headline set is_deleted = 1 where hid = ?";
        return baseUpdate(sql,hid);
    }
}
复制代码
NewsTypeDaoImpl实现类
java 复制代码
public class NewsTypeDaoImpl extends BaseDao implements NewsTypeDao {
    @Override
    public List<NewsType> findAll() {
        String sql = "select tid,tname from news_type";
        return baseQuery(NewsType.class,sql);
    }
}
复制代码
NewsUserDaoImpl实现类
java 复制代码
public class NewsUserDaoImpl extends BaseDao implements NewsUserDao {
    @Override
    public NewsUser findByUsername(String username) {
        String sql = """
                select
                    uid,
                    username,
                    user_pwd userPwd,
                    nick_name nickName 
                from 
                    news_user
                where
                    username = ?
                """;
        List<NewsUser> newsUserList = baseQuery(NewsUser.class, sql, username);
        return newsUserList != null  && newsUserList.size()>0 ? newsUserList.get(0):null ;
    }

    @Override
    public NewsUser findByUid(Integer userId) {
        String sql = """
                select
                    uid,
                    username,
                    user_pwd userPwd,
                    nick_name nickName 
                from 
                    news_user
                where
                    uid = ?
                """;
        List<NewsUser> newsUserList = baseQuery(NewsUser.class, sql, userId);
        return newsUserList != null  && newsUserList.size()>0 ? newsUserList.get(0):null ;

    }

    @Override
    public Integer insertUser(NewsUser registUser) {
        String sql = """
                insert into news_user values (DEFAULT,?,?,?)
                """;
        return baseUpdate(sql,
                registUser.getUsername(),
                registUser.getUserPwd(),
                registUser.getNickName()
                );
    }
}

service层

复制代码
NewsHeadlineService接口
java 复制代码
public interface NewsHeadlineService {
    /**
     *
     * @param headlineQueryVo
     * @return
     */
    Map findPage(HeadlineQueryVo headlineQueryVo);

    /**
     *
     * @param hid
     * @return
     */
    HeadlineDetailVo findHeadlineDetail(int hid);

    /**
     *
     * @param newsHeadline
     */
    int addNewsHeadline(NewsHeadline newsHeadline);

    /**
     *
     * @param hid
     * @return
     */
    NewsHeadline findByHid(Integer hid);

    int update(NewsHeadline newsHeadline);


    /**
     *
     * @param hid
     * @return
     */
    int removeByHid(int hid);
}
复制代码
NewsTypeService接口
java 复制代码
public interface NewsTypeService {
    /**
     * 查询所有头条类型的方法
     * @return 多个头条类型以List<NewsType>集合形式返回
     */
    List<NewsType> findAll();
}
复制代码
NewsUserService接口
java 复制代码
public interface NewsUserService {
    /**
     * 根据用户登录的账号找用户新的方法
     * @param username 用户输入的账户
     * @return 找到返回NewsUser对象,找不到返回null
     */
    NewsUser findByUsername(String username);

    /**
     *
     * @param userId
     * @return
     */
    NewsUser findByUid(Integer userId);

    /**
     *
     * @param registUser
     * @return
     */
    Integer registUser(NewsUser registUser);
}
复制代码
NewsHeadlineServiceImpl实现类
java 复制代码
public class NewsHeadlineServiceImpl implements NewsHeadlineService {
    private NewsHeadlineDao headlineDao =new NewsHeadlineDaoImpl();
    /*
        totalPage:1,
        totalSize:1
        pageData:[
                    {
                       "hid":"1",                     // 新闻id
                        "title":"尚硅谷宣布 ... ...",   // 新闻标题
                        "type":"1",                    // 新闻所属类别编号
                        "pageViews":"40",              // 新闻浏览量
                        "pastHours":"3",              // 发布时间已过小时数
                        "publisher":"1"
                   }
                 ],
        pageNum:1,
        pageSize:1,


     */
    @Override

    public Map findPage(HeadlineQueryVo headlineQueryVo) {
        int pageNum = headlineQueryVo.getPageNum();
        int pageSize = headlineQueryVo.getPageSize();
        List<HeadlinePageVo> pageData = headlineDao.findPageList(headlineQueryVo);
        int totalSize = headlineDao.findPageCount(headlineQueryVo);

        int totalPage =totalSize % pageSize ==0 ? totalSize/pageSize: totalSize/pageSize+1;
        Map pageInfo= new HashMap();
        pageInfo.put("pageNum",pageNum);
        pageInfo.put("pageSize",pageSize);
        pageInfo.put("totalSize",totalSize);
        pageInfo.put("totalPage",totalPage);
        pageInfo.put("pageData",pageData);
        return pageInfo;
    }

    @Override
    public HeadlineDetailVo findHeadlineDetail(int hid) {
        // 修改该头条的浏览量  +1
        headlineDao.incrPageViews(hid);
        // 查询头条的详情
        return headlineDao.findHealineDetail(hid);
    }

    @Override
    public int addNewsHeadline(NewsHeadline newsHeadline) {
        return headlineDao.addNewsHeadline(newsHeadline);
    }

    @Override
    public NewsHeadline findByHid(Integer hid) {
        return headlineDao.findByHid(hid);
    }

    @Override
    public int update(NewsHeadline newsHeadline) {
        return headlineDao.update(newsHeadline);
    }

    @Override
    public int removeByHid(int hid) {
        return headlineDao.removeByHid(hid);
    }
}
复制代码
NewsTypeServiceImpl实现类
java 复制代码
public class NewsTypeServiceImpl implements NewsTypeService {
    private NewsTypeDao typeDao =new NewsTypeDaoImpl();
    @Override
    public List<NewsType> findAll() {
        return typeDao.findAll();
    }
}
复制代码
NewsUserServiceImpl实现类
java 复制代码
public class NewsUserServiceImpl implements NewsUserService {

    private NewsUserDao userDao =new NewsUserDaoImpl();
    @Override
    public NewsUser findByUsername(String username) {
        return userDao.findByUsername(username);
    }

    @Override
    public NewsUser findByUid(Integer userId) {
        return userDao.findByUid(userId);
    }

    @Override
    public Integer registUser(NewsUser registUser) {
        // 处理增加数据的业务
        // 将明文密码转换成密文密码
        registUser.setUserPwd(MD5Util.encrypt(registUser.getUserPwd()));

        return userDao.insertUser(registUser);
    }
}

servlet层

复制代码
NewsHeadlineController
java 复制代码
@WebServlet("/headline/*")
public class NewsHeadlineController extends BaseController{
    private NewsHeadlineService headlineService =new NewsHeadlineServiceImpl();


    /**
     * 删除头条业务接口 实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void removeByHid(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        int hid = Integer.parseInt(req.getParameter("hid"));

        headlineService.removeByHid(hid);


        WebUtil.writeJson(resp, Result.ok(null));
    }

    /**
     * 更新头条的业务接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */

    protected void update(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        NewsHeadline newsHeadline = WebUtil.readJson(req, NewsHeadline.class);
        headlineService.update(newsHeadline);

        WebUtil.writeJson(resp,Result.ok(null));

    }

    /**
     * 修改头条回显业务接口
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void findHeadlineByHid(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        Integer hid = Integer.parseInt(req.getParameter("hid"));
        NewsHeadline headline =headlineService.findByHid(hid);

        Map data =new HashMap();
        data.put("headline",headline);
        WebUtil.writeJson(resp,Result.ok(data));

    }

    /**
     * 发布头条的接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void publish(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收参数
        String token = req.getHeader("token");
        Long userId = JwtHelper.getUserId(token);


        NewsHeadline newsHeadline = WebUtil.readJson(req, NewsHeadline.class);
        newsHeadline.setPublisher(userId.intValue());


        // 将信息存入数据库
        headlineService.addNewsHeadline(newsHeadline);

        WebUtil.writeJson(resp, Result.ok(null));

    }
}
复制代码
NewsTypeController
java 复制代码
@WebServlet("/type/*")
public class NewsTypeController extends BaseController{
}
复制代码
NewsUserController
java 复制代码
@WebServlet("/user/*")
public class NewsUserController extends BaseController{


    private NewsUserService userService =new NewsUserServiceImpl();


    /**
     * 前端自己校验是否失去登录状态的接口
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void checkLogin(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String token = req.getHeader("token");

        Result result= Result.build(null, ResultCodeEnum.NOTLOGIN);
        if(null != token){
            if (!JwtHelper.isExpiration(token)) {
                result= Result.ok(null);
            }
        }
        WebUtil.writeJson(resp,result);
    }

    /**
     * 完成注册的业务接口
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void regist(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收JSON信息
        NewsUser registUser = WebUtil.readJson(req, NewsUser.class);

        // 调用服务层将用户信息存入数据
        Integer rows =userService.registUser(registUser);

        // 根据存入是否成功处理响应值
        Result result =Result.ok(null);
        if(rows == 0){
            result=Result.build(null,ResultCodeEnum.USERNAME_USED);
        }

        WebUtil.writeJson(resp,result);

    }

    /**
     * 校验用户名是否被占用的业务接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void checkUserName(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 获取账号
        String username = req.getParameter("username");

        // 根据用户名查询用户信息  找到了 返回505  找不到 200
        NewsUser newsUser = userService.findByUsername(username);
        Result result =Result.ok(null);
        if(null != newsUser){
            result=Result.build(null,ResultCodeEnum.USERNAME_USED);
        }

        WebUtil.writeJson(resp,result);
    }

    /**
     * 根据token口令获得用户信息的接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void getUserInfo(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 获取请求中的token
        String token = req.getHeader("token");


        Result result = Result.build(null,ResultCodeEnum.NOTLOGIN);
        if(null != token && (!"".equals(token))){
            if (!JwtHelper.isExpiration(token)) {
                Integer userId = JwtHelper.getUserId(token).intValue();
                NewsUser newsUser =userService.findByUid(userId);
                if(null != newsUser){
                    //通过校验 查询用户信息放入Result
                    Map data =new HashMap();
                    newsUser.setUserPwd("");
                    data.put("loginUser",newsUser);

                    result = Result.ok(data);
                }
            }
        }

        WebUtil.writeJson(resp,result);

    }

    /**
     * 处理登录表单提交的业务接口的实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void login(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收用户名和密码
        /*{
            "username":"zhangsan", //用户名
            "userPwd":"123456"     //明文密码
        }*/
        NewsUser paramUser = WebUtil.readJson(req, NewsUser.class);

        // 调用服务层方法 实现登录
        NewsUser loginUser = userService.findByUsername(paramUser.getUsername());
        Result result = null;
        if(null != loginUser){
            if (MD5Util.encrypt(paramUser.getUserPwd()).equalsIgnoreCase(loginUser.getUserPwd())) {
                Map data =new HashMap();
                data.put("token",JwtHelper.createToken(loginUser.getUid().longValue()));
                result=Result.ok(data);
            }else{
                result=Result.build(null,ResultCodeEnum.PASSWORD_ERROR);
            }
        }else {
            result=Result.build(null, ResultCodeEnum.USERNAME_ERROR);

        }

        // 向客户端响应登录验证信息
        WebUtil.writeJson(resp,result);
    }
}
复制代码
PortalController(分页)
java 复制代码
@WebServlet("/portal/*")
public class PortalController extends BaseController{
    private NewsTypeService typeService =new NewsTypeServiceImpl();
    private NewsHeadlineService headlineService =new NewsHeadlineServiceImpl();


    /**
     * 查询头条详情的业务接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void showHeadlineDetail(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收要查询头条的hid
        int hid = Integer.parseInt(req.getParameter("hid"));
        // 调用服务层完成查询处理
        HeadlineDetailVo headlineDetailVo =headlineService.findHeadlineDetail(hid);
        // 将查到的信息响应给客户端
        Map data =new HashMap();
        data.put("headline",headlineDetailVo);
        WebUtil.writeJson(resp, Result.ok(data));
    }

    /**
     * 分页查询头条信息的接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void findNewsPage(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 接收请求中的参数
        HeadlineQueryVo headlineQueryVo = WebUtil.readJson(req, HeadlineQueryVo.class);


        // 将参数传递给服务层 进行分页查询
        /*
        * pageData:[
        *   {
        *           "hid":"1",                     // 新闻id
    				"title":"尚硅谷宣布 ... ...",   // 新闻标题
    				"type":"1",                    // 新闻所属类别编号
    				"pageViews":"40",              // 新闻浏览量
    				"pastHours":"3",              // 发布时间已过小时数
    				"publisher":"1"
        *   }
        *
        * ],
        * pageNum:1,
        * pageSize:1,
        * totalPage:1,
        * totalSize:1
        *
        *
        * */
       Map pageInfo =headlineService.findPage(headlineQueryVo);
       Map data =new HashMap();
       data.put("pageInfo",pageInfo);

        // 将分页查询的结果转换成json响应给客户端
        WebUtil.writeJson(resp,Result.ok(data));
    }

    /**
     * 查询所有头条类型的业务接口实现
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */

    protected void findAllTypes(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        // 查询所有的新闻类型,装入Result响应给客户端
        List<NewsType> newsTypeList= typeService.findAll();


        WebUtil.writeJson(resp,Result.ok(newsTypeList));
    }
}

项目实战二结束

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