[JavaWeb]微头条项目-2 项目框架源码和注解

2024-11-21 14:41:57

2.1 工具类

2.1.1 异步响应规范格式类

  • Result类
package com.atguigu.headline.common;

/**
 * 全局统一返回结果类
 *
 */
public class Result<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) {
        Result<T> result = new Result<T>();
        if (data != null)
            result.setData(data);
        return result;
    }
    public static <T> Result<T> build(T body, Integer code, String message) {
        Result<T> result = build(body);
        result.setCode(code);
        result.setMessage(message);
        return result;
    }
    public static <T> Result<T> build(T body, ResultCodeEnum resultCodeEnum) {
        Result<T> result = build(body);
        result.setCode(resultCodeEnum.getCode());
        result.setMessage(resultCodeEnum.getMessage());
        return result;
    }
    /**
     * 操作成功
     * @param data  baseCategory1List
     * @param <T>
     * @return
     */
    public static<T> Result<T> ok(T data){
        Result<T> result = build(data);
        return build(data, ResultCodeEnum.SUCCESS);
    }
    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;
    }
}
  • ResultCodeEnum 枚举类
package com.atguigu.headline.common;
/**
 * 统一返回结果状态信息类
 *
 */
public enum ResultCodeEnum {

    SUCCESS(200,"success"),
    USERNAME_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;
    }
}

2.1.2 MD5加密工具类

package com.atguigu.headline.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public final 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();
            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！！+" + e);
        }
    }
}

2.1.3 JDBCUtil连接池工具类

package com.atguigu.headline.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);
            }
        }
    }
}

添加jdbc.properties配置文件

driverClassName=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/top_news
username=root
password=root
initialSize=5
maxActive=10
maxWait=1000

2.1.4 JwtHelper工具类

package com.atguigu.headline.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;
        }
    }
}

2.1.5 JSON转换的WEBUtil工具类

package com.atguigu.headline.util;

import com.atguigu.headline.common.Result;
import com.fasterxml.jackson.databind.ObjectMapper;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

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);
        }
    }
}

2.2 实体类和VO对象

2.2.1 NewsUser

package com.atguigu.headline.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;

@AllArgsConstructor
@NoArgsConstructor
@Data
public class NewsUser implements Serializable {
    private Integer uid;
    private String username;
    private String userPwd;
    private String nickName;
}

2.2.2 NewsType

package com.atguigu.headline.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;

@AllArgsConstructor
@NoArgsConstructor
@Data
public class NewsType implements Serializable {
    private Integer tid;
    private String tname;
}

2.2.3 NewsHeadline

package com.atguigu.headline.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;
import java.util.Date;

@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;

}

2.2.4 HeadlineQueryVo

package com.atguigu.headline.pojo.vo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;

@AllArgsConstructor
@NoArgsConstructor
@Data
public class HeadlineQueryVo implements Serializable {
    private String keyWords;
    private Integer type ;
    private Integer pageNum;
    private Integer pageSize;
}

2.2.5 HeadlinePageVo

package com.atguigu.headline.pojo.vo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;

@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;
}

2.2.6 HeadlineDetailVo

package com.atguigu.headline.pojo.vo;


import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.io.Serializable;

@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;
}

2.3 Dao层

在这里插入图片描述

BaseDao基础类,封装了公共的查询方法和公共的增删改方法

注意,所有的Dao接口的实现类都要继承BaseDao

2.3.1 BaseDao

package com.atguigu.headline.dao;


import com.atguigu.headline.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 {
    // 公共的查询方法  返回的是单个对象
    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) {
            throw new RuntimeException(e);
        } 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 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) {
            throw new RuntimeException(e);
        } 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) {
            throw new RuntimeException(e);
        } 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;
    }
}

2.3.2 Dao层所有接口

package com.atguigu.headline.dao;
public interface NewsHeadLineDao {
    
}

package com.atguigu.headline.dao;
public interface NewsTypeDao {
    
}


package com.atguigu.headline.dao;
public interface NewsUserDao {

}

2.3.3 dao层所有实现类

package com.atguigu.headline.dao.impl;
import com.atguigu.headline.dao.BaseDao;
import com.atguigu.headline.dao.NewsHeadLineDao;
public class NewsHeadlineDaoImpl extends BaseDao implements NewsHeadLineDao{
    
}

package com.atguigu.headline.dao.impl;
import com.atguigu.headline.dao.BaseDao;
import com.atguigu.headline.dao.NewsTypeDao;
public class NewsTypeDaoImpl extends BaseDao implements NewsTypeDao{
    
}

package com.atguigu.headline.dao.impl;
import com.atguigu.headline.dao.BaseDao;
import com.atguigu.headline.dao.NewsUserDao;
public class NewsUserDaoImpl extends BaseDao implements NewsUserDao{
    
}

2.4 Service层

在这里插入图片描述

2.4.1 service层所有接口

package com.atguigu.headline.service;
public interface NewsHeadlineService {
    
}

package com.atguigu.headline.service;
public interface NewsTypeService {
    List<NewsType> findAll();
}

package com.atguigu.headline.service;
public interface NewsUserService {
    
}

2.4.2 service层所有实现类

package com.atguigu.headline.service.impl;
import com.atguigu.headline.service.NewsHeadlineService;
public class NewsHeadlineServiceImpl  implements NewsHeadlineService {
}


package com.atguigu.headline.service.impl;
import com.atguigu.headline.service.NewsTypeService;
public class NewsTypeServiceImpl implements NewsTypeService {
  
}

package com.atguigu.headline.service.impl;
import com.atguigu.headline.service.NewsUserService;
public class NewsUserServiceImpl implements NewsUserService {
   
}

2.5 Controller层

BaseController 用于将路径关联到处理方法的基础控制器，所有的Controller都要继承该类

2.5.1 BaseController

package com.atguigu.headline.controller;

import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

import java.io.IOException;
import java.lang.reflect.Method;

public class BaseController extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 响应的MIME类型和乱码问题
        resp.setContentType("application/json;charset=UTF-8");

        String requestURI = req.getRequestURI();
        String[] split = requestURI.split("/");
        String methodName =split[split.length-1];
        // 通过反射获取要执行的方法
        Class clazz = this.getClass();
        try {
            Method method=clazz.getDeclaredMethod(methodName,HttpServletRequest.class,HttpServletResponse.class);
            // 设置方法可以访问
            method.setAccessible(true);
            // 通过反射执行代码
            method.invoke(this,req,resp);
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException(e.getMessage());
        }
    }
}

2.5.2 所有的Controller类

package com.atguigu.headline.controller;
import jakarta.servlet.annotation.WebServlet;
@WebServlet("/headline/*")
public class NewsHeadlineController extends BaseController {
    
}

package com.atguigu.headline.controller;
import jakarta.servlet.annotation.WebServlet;
@WebServlet("/type/*")
public class NewsTypeController {
    
}

package com.atguigu.headline.controller;
import jakarta.servlet.annotation.WebServlet;
@WebServlet("/user/*")
public class NewsUserController extends BaseController{
    
}

package com.atguigu.headline.controller;
import jakarta.servlet.annotation.WebServlet;
@WebServlet("/portal/*")
public class PortalController extends BaseController{
    
}

2.6 过滤器

2.6.1 跨域过滤器

package com.atguigu.headline.filters;

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 {
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        HttpServletRequest request =(HttpServletRequest) servletRequest;
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, 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);
        }
    }
}
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