后端架构完善与接口开发

数据库准备

数据库的创建，选择名为wiki，排序规则为：utf8mb4 --UTF-8 Unicode

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DROP TABLE IF EXIT `test`;
CREATE TABLE `test`(
	`id` BIGINT NOT NULL COMMENT 'id',
	`name` VARCHAR(50) COMMENT '名称',
	`password` VARCHAR(50) COMMENT '密码',
	PRIMARY KEY (`id`)
	
) ENGINE=INNODB DEFAULT CHARSET=utf8mb4 COMMENT='测试';

IDEA数据库插件配置

集成持久层框架Mybatis

1.名词

  • 持久层
  • ORM

2.集成Mybatis

配置数据源

  • 引入依赖：porm.xml

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    <!-- 集成mybatis-->
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>2.1.3</version>
    </dependency>
    <!-- 集成mysql连接 -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.22</version>

  • 增加数据库连接：application.properties

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    # 增加数据库连接
    spring.datasource.url=jdbc:mysql://localhost:3306/wiki?characterEncoding=UTF8&autoReconnect=true&serverTimezone=Asia/Shanghai&allowMultiQueries=true
    spring.datasource.username=root
    spring.datasource.password=*****
    spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

3.使用Mybatis

  • 配置mybatis所有Mapper.xml所在的路径application.properties

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    # 配置mybatis所有Mapper.xml所在的路径
    mybatis.mapper-locations=classpath:/mapper/**/*.xml

  • 使用@MapperScan扫描所有的Mapper接口，让其知道wiki.mapper下面的持久层

    • @MapperScan("com.javami.wiki.mapper") 接口和XML的命名
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@ComponentScan("com.javami")
@SpringBootApplication
@MapperScan("com.javami.wiki.mapper")
public class WikiApplication {
    private static final Logger LOG = LoggerFactory.getLogger(WikiApplication.class);
    public static void main(String[] args) {
        SpringApplication.run(WikiApplication.class, args);
        LOG.info("启动成功！！");
    }
}

4.关于mapper文件下的xxMapper.xml的解释，id对应xxMapper.java对应的方法名，namespace对应xxMapper.java接口的具体类位置。比如：com.jiawa.wiki.mapper.TestMapper

5.Free Mybatis plugin插件可以做代码跳转

6.使用@Service或@RestController注解，将Service类或Controller类交给Spring来管理了。

  • 使用@Resource或@Autowire将一个类注入到另一个类中
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//将Service类或Controller类交给Spring来管理了
@Service
public class TestService {
    //将TestMapper注入进来
    @Resource
    private TestMapper testMapper;

    public List<Test> list() {
        return testMapper.list();
    }
}

集成Mybatis官方代码生成器

1.如何集成Mybatis Generator

  • 增加插件依赖porm.xml
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    <!-- mybatis generator 自动生成代码插件 -->
                <plugin>
                    <groupId>org.mybatis.generator</groupId>
                    <artifactId>mybatis-generator-maven-plugin</artifactId>
                    <version>1.4.0</version>
                    <configuration>
                        <configurationFile>src/main/resources/generator/generator-config.xml</configurationFile>
                        <overwrite>true</overwrite>
                        <verbose>true</verbose>
                    </configuration>
                    <dependencies>
                        <dependency>
                            <groupId>mysql</groupId>
                            <artifactId>mysql-connector-java</artifactId>
                            <version>8.0.22</version>
                        </dependency>
                    </dependencies>
                </plugin>
  • 到resources文件夹下创建generator文件夹增加配置文件generator-config.xml
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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
    <context id="Mysql" targetRuntime="MyBatis3" defaultModelType="flat">

        <!-- 自动检查关键字，为关键字增加反引号 -->
        <property name="autoDelimitKeywords" value="true"/>
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>

        <!--覆盖生成XML文件-->
        <plugin type="org.mybatis.generator.plugins.UnmergeableXmlMappersPlugin" />
        <!-- 生成的实体类添加toString()方法 -->
        <plugin type="org.mybatis.generator.plugins.ToStringPlugin"/>

        <!-- 不生成注释 -->
        <commentGenerator>
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>

        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://rm-uf6470s9615e13hc4no.mysql.rds.aliyuncs.com:3306/wikidev?serverTimezone=Asia/Shanghai"
                        userId="wikidev"
                        password="wikidevABC123">
        </jdbcConnection>

        <!-- domain类的位置 -->
        <javaModelGenerator targetProject="src\main\java"
                            targetPackage="com.jiawa.wiki.domain"/>

        <!-- mapper xml的位置 -->
        <sqlMapGenerator targetProject="src\main\resources"
                         targetPackage="mapper"/>

        <!-- mapper类的位置 -->
        <javaClientGenerator targetProject="src\main\java"
                             targetPackage="com.jiawa.wiki.mapper"
                             type="XMLMAPPER"/>

        <!--<table tableName="demo" domainObjectName="Demo"/>-->
        <!--<table tableName="ebook"/>-->
        <!--<table tableName="category"/>-->
        <!--<table tableName="doc"/>-->
        <!--<table tableName="content"/>-->
        <!--<table tableName="user"/>-->
        <table tableName="ebook_snapshot"/>
    </context>
</generatorConfiguration>
  • 增加执行命令

2.RequestMapping 注解也可以用在类上面

电子书列表查询接口开发

1.创建ebook表

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DROP TABLE IF EXIT `ebook`;
CREATE TABLE `ebook`(
	`id` BIGINT NOT NULL COMMENT 'id',
	`name` VARCHAR(50) COMMENT '名称',
	`category1_id` BIGINT COMMENT '分类1',
	`category2_id` BIGINT COMMENT '分类2',
	`description` VARCHAR(200) COMMENT '描述',
  `cover` VARCHAR(200) COMMENT '封面',
	`doc_count` int COMMENT '文档数',
	`view_count` int COMMENT '阅读数',
	`vote_count` int COMMENT '点赞数',
PRIMARY KEY (`id`)
	
) ENGINE=INNODB DEFAULT CHARSET=utf8mb4 COMMENT='电子书';


INSERT INTO `ebook` (id,name,description) VALUES(1,'spring Boot入门教程','；零基础开发入门，企业级开发最佳框架');

2.配置generator-config.xml，生成Mybatis的mapper

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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
    <context id="Mysql" targetRuntime="MyBatis3" defaultModelType="flat">

        <!-- 自动检查关键字，为关键字增加反引号 -->
        <property name="autoDelimitKeywords" value="true"/>
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>

        <!--覆盖生成XML文件-->
        <plugin type="org.mybatis.generator.plugins.UnmergeableXmlMappersPlugin" />
        <!-- 生成的实体类添加toString()方法 -->
        <plugin type="org.mybatis.generator.plugins.ToStringPlugin"/>

        <!-- 不生成注释 -->
        <commentGenerator>
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>

        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://rm-uf6470s9615e13hc4no.mysql.rds.aliyuncs.com:3306/wikidev?serverTimezone=Asia/Shanghai"
                        userId="wikidev"
                        password="wikidevABC123">
        </jdbcConnection>

        <!-- domain类的位置 -->
        <javaModelGenerator targetProject="src\main\java"
                            targetPackage="com.jiawa.wiki.domain"/>

        <!-- mapper xml的位置 -->
        <sqlMapGenerator targetProject="src\main\resources"
                         targetPackage="mapper"/>

        <!-- mapper类的位置 -->
        <javaClientGenerator targetProject="src\main\java"
                             targetPackage="com.jiawa.wiki.mapper"
                             type="XMLMAPPER"/>

        <!--<table tableName="demo" domainObjectName="Demo"/>-->
        <!--<table tableName="ebook"/>-->
        <!--<table tableName="category"/>-->
        <!--<table tableName="doc"/>-->
        <!--<table tableName="content"/>-->
        <!--<table tableName="user"/>-->
        <table tableName="ebook_snapshot"/>
    </context>
</generatorConfiguration>

3.配置service层下的EbookService.java

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@Service
public class EbookService {

    @Resource
    private EbookMapper ebookMapper;

    public List<EbookResp> list(EbookReq req) {
        EbookExample ebookExample = new EbookExample();
        EbookExample.Criteria criteria = ebookExample.createCriteria();
        if (!ObjectUtils.isEmpty(req.getName())) {
            criteria.andNameLike("%" + req.getName() + "%");
        }
        List<Ebook> ebookList = ebookMapper.selectByExample(ebookExample);

        // List<EbookResp> respList = new ArrayList<>();
        // for (Ebook ebook : ebookList) {
        //     // EbookResp ebookResp = new EbookResp();
        //     // BeanUtils.copyProperties(ebook, ebookResp);
        //     // 对象复制
        //     EbookResp ebookResp = CopyUtil.copy(ebook, EbookResp.class);
        //
        //     respList.add(ebookResp);
        // }

        // 列表复制
        List<EbookResp> list = CopyUtil.copyList(ebookList, EbookResp.class);

        return list;
    }
}

4.配置controller层下的EbookController.java

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@RestController
@RequestMapping("/ebook")
public class EbookController {
    @Resource
    private EbookService ebookService;

    @GetMapping("list")
    public List<Ebook> list(){
        return ebookService.list();
    }
}

5.后端接口统一返回参数，方便前端统一处理

①创建resp文件夹，创建CommonResp.java

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package com.jiawa.wiki.resp;

public class CommonResp<T> {

    /**
     * 业务上的成功或失败
     */
    private boolean success = true;

    /**
     * 返回信息
     */
    private String message;

    /**
     * 返回泛型数据，自定义类型
     */
    private T content;

    public boolean getSuccess() {
        return success;
    }

    public void setSuccess(boolean success) {
        this.success = success;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public T getContent() {
        return content;
    }

    public void setContent(T content) {
        this.content = content;
    }

    @Override
    public String toString() {
        final StringBuffer sb = new StringBuffer("ResponseDto{");
        sb.append("success=").append(success);
        sb.append(", message='").append(message).append('\'');
        sb.append(", content=").append(content);
        sb.append('}');
        return sb.toString();
    }
}

②controller层下修改EbookController.java，使其后端返回统一参数

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@RestController
@RequestMapping("/ebook")
public class EbookController {
    @Resource
    private EbookService ebookService;

    @GetMapping("list")
    public CommonResp list(){
        CommonResp<List<Ebook>> resp = new CommonResp<>();
        List<Ebook> list = ebookService.list();
        resp.setContent(list);
        return resp;
    }
}

封装请求参数和返回参数

1.封装请求和返回参数

  • XXXReq
  • XXXResp

①创建req包，创建EbookReq.java文件

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package com.javami.wiki.req;

/**
 * @author Kevin
 * @create 2021-08-03 22:41
 */
public class EbookReq {
    private Long id;

    private String name;

    public Long getId() {
        return id;
    }


    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "EbookReq{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }
}

②创建resp包，EbookResp.java文件

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package com.javami.wiki.resp;

/**
 * @author Kevin
 * @create 2021-08-03 22:59
 */
public class EbookResp {
    private String name;

    private Long category1Id;

    private Long category2Id;

    private String description;

    private String cover;

    private Integer docCount;

    private Integer viewCount;

    private Integer voteCount;
    

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Long getCategory1Id() {
        return category1Id;
    }

    public void setCategory1Id(Long category1Id) {
        this.category1Id = category1Id;
    }

    public Long getCategory2Id() {
        return category2Id;
    }

    public void setCategory2Id(Long category2Id) {
        this.category2Id = category2Id;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getCover() {
        return cover;
    }

    public void setCover(String cover) {
        this.cover = cover;
    }

    public Integer getDocCount() {
        return docCount;
    }

    public void setDocCount(Integer docCount) {
        this.docCount = docCount;
    }

    public Integer getViewCount() {
        return viewCount;
    }

    public void setViewCount(Integer viewCount) {
        this.viewCount = viewCount;
    }

    public Integer getVoteCount() {
        return voteCount;
    }

    public void setVoteCount(Integer voteCount) {
        this.voteCount = voteCount;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append(getClass().getSimpleName());
        sb.append(" [");
        sb.append("Hash = ").append(hashCode());
        sb.append(", name=").append(name);
        sb.append(", category1Id=").append(category1Id);
        sb.append(", category2Id=").append(category2Id);
        sb.append(", description=").append(description);
        sb.append(", cover=").append(cover);
        sb.append(", docCount=").append(docCount);
        sb.append(", viewCount=").append(viewCount);
        sb.append(", voteCount=").append(voteCount);
        sb.append("]");
        return sb.toString();
    }
}

②修改controller包下的EbookController.java，让其请求是Ebookreq的

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@RestController
@RequestMapping("/ebook")
public class EbookController {
    @Resource
    private EbookService ebookService;

    @GetMapping("list")
    public CommonResp list(EbookReq req){
        CommonResp<List<EbookResp>> resp = new CommonResp<>();
        List<EbookResp> list = ebookService.list(req);
        resp.setContent(list);
        return resp;
    }
}

②修改service包下的EbookService.java，接受路由传递进来的Ebookreq

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@Service
public class EbookService {

    @Resource
    private EbookMapper ebookMapper;

    public List<EbookResp> list(EbookReq req){
        EbookExample ebookExample = new EbookExample();
        EbookExample.Criteria criteria = ebookExample.createCriteria();
        criteria.andNameLike("%"+req.getName()+"%");
        List<Ebook> ebookList = ebookMapper.selectByExample(ebookExample);

        List<EbookResp> respList = new ArrayList<>();
        for(Ebook ebook: ebookList){
            EbookResp ebookResp = new EbookResp();
            //BeanUtils工具类的使用
            BeanUtils.copyProperties(ebook,ebookResp);
            respList.add(ebookResp);
        }

        return respList;
    }
}

③测试

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http://localhost:8880/ebook/list?name=spring

制作CopyUtil封装BeanUtils

1.CopyUtil工具类

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package com.jiawa.wiki.util;

import org.springframework.beans.BeanUtils;
import org.springframework.util.CollectionUtils;

import java.util.ArrayList;
import java.util.List;

public class CopyUtil {

    /**
     * 单体复制
     */
    public static <T> T copy(Object source, Class<T> clazz) {
        if (source == null) {
            return null;
        }
        T obj = null;
        try {
            obj = clazz.newInstance();
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
        BeanUtils.copyProperties(source, obj);
        return obj;
    }

    /**
     * 列表复制
     */
    public static <T> List<T> copyList(List source, Class<T> clazz) {
        List<T> target = new ArrayList<>();
        if (!CollectionUtils.isEmpty(source)){
            for (Object c: source) {
                T obj = copy(c, clazz);
                target.add(obj);
            }
        }
        return target;
    }
}

使用CopyUtil优化service包下的EbookService.java

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        for(Ebook ebook: ebookList){
//            EbookResp ebookResp = new EbookResp();
//            BeanUtils.copyProperties(ebook,ebookResp);
            EbookResp ebookResp = CopyUtil.copy(ebook,EbookResp.class);
            respList.add(ebookResp);
        }

2.如果代码改动了，但是出现莫名其妙的错，可以试一下maven clean，比如：

  • 代码没错却编译出错
  • 测试结果跟代码不符
  • 引入了jar包却没反应
wiki知识系统
Vue3 Spring Boot

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