SpringBoot构建微服务实战之整合Mybatis(二)

谁借莪１个温暖的怀抱￠ 2022-05-25 09:21 247阅读 0赞

## 前言 ##

本节我们将学习一下SpringBoot整合Mybatis，首先说明一下，SpringBoot 整合Mybatis主流的由两种：基于注解形式的，基于配置形式的(推荐使用。)

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## 基于注解的整合 ##

我之前有些过一篇，请移步至：[SpringBoot构建微服务实战 之 整合Mybatis(一)][SpringBoot_ _ _Mybatis]

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## 基于配置的整合 ##

首先SpringBoot 以配置的方式整合Mybatis 的先决条件：需要配置DataSource，因而本节将基于 [SpringBoot构建微服务实战 之 DataSource(二)][SpringBoot_ _ DataSource] 来学习。

*  **Maven 构建新的SpringBoot项目**  
    ![这里写图片描述][70]
 *  引入Mybatis及相关依赖
    
        <properties>
                <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
                <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
                <mybatis-spring-boot-starter.version>1.1.1</mybatis-spring-boot-starter.version>
                <mybatisplus-spring-boot-starter.version>1.0.4</mybatisplus-spring-boot-starter.version>
                <java.version>1.8</java.version>
            </properties>
        
            <dependencies>
                
                <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-web</artifactId>
                </dependency>
        
                
                <dependency>
                    <groupId>org.mybatis.spring.boot</groupId>
                    <artifactId>mybatis-spring-boot-starter</artifactId>
                    <version>${mybatis-spring-boot-starter.version}</version>
                </dependency>
                <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-jdbc</artifactId>
                </dependency>
        
                <dependency>
                    <groupId>mysql</groupId>
                    <artifactId>mysql-connector-java</artifactId>
                    <scope>runtime</scope>
                </dependency>
        
                
                <dependency>
                    <groupId>com.alibaba</groupId>
                    <artifactId>druid</artifactId>
                    <version>1.1.8</version>
                </dependency>
        
                
        
                <dependency>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-test</artifactId>
                    <scope>test</scope>
                </dependency>
            </dependencies>
        
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-maven-plugin</artifactId>
                    </plugin>
                </plugins>
            </build>
 *  编写逻辑
    
     *  ExmapleController.java
        
            @Controller
            @RequestMapping("/emxaple")
            public class ExmapleController { 
            
                @Autowired
                private ExmapleSercive exmapleService;
            
                @RequestMapping("/addLock")
                @ResponseBody
                public int addLock() throws Exception{
                    int ret = -1;
                    Lock lock = new Lock("123","456");
                    ret = exmapleService.insertLock(lock);
                    return ret;
            
                }
            }
     *  ExmapleDao.java
        
            public interface ExmapleDao {
            
                public int insertLock(Lock lock);
            }
     *  Lock.java
        
            public class Lock implements Serializable { 
            
                private String schedName;
                private String lockName;
            
            
                @Override
                public String toString() {
                    return "Lock [schedName=" + schedName + ", lockName=" + lockName + "]";
                }
            
            
                public String getSchedName() {
                    return schedName;
                }
            
            
                public void setSchedName(String schedName) {
                    this.schedName = schedName;
                }
            
            
                public String getLockName() {
                    return lockName;
                }
            
            
                public void setLockName(String lockName) {
                    this.lockName = lockName;
                }
            
            
                public Lock() {
                    super();
                }
            
            
                public Lock(String schedName, String lockName) {
                    super();
                    this.schedName = schedName;
                    this.lockName = lockName;
                }
            
            
            
            }
     *  ExmapleSercive.java
        
            public interface ExmapleSercive {
            
                public int insertLock(Lock lock);
            }
     *  ExmapleServiceImpl.java
        
            @Service("exmapleService")
            public class ExmapleServiceImpl implements ExmapleSercive { 
            
                @Autowired 
                private ExmapleDao exmapleDao;
            
                @Override
                public int insertLock(Lock lock) {
                    int ret = -1;
                    try {
                        ret = exmapleDao.insertLock(lock);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                    return ret;
                }
            
            
            }
     *  DruidExmapleApplication.java
        
            @SpringBootApplication
            @MapperScan("com.example.demo.dao")
            public class DruidExmapleApplication { 
            
                public static void main(String[] args) {
                    SpringApplication.run(DruidExmapleApplication.class, args);
                }
            }
 *  application.yml 全局设置
    
        #dubbo配置
        
        spring:
          datasource:
            type: com.alibaba.druid.pool.DruidDataSource
            driverClassName: com.mysql.jdbc.Driver
            #url: jdbc:mysql://10.213.24.45:3306/demo2?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull
            url: jdbc:mysql://localhost:3306/demo2?useUnicode=true&characterEncoding=utf8&useSSL=false&zeroDateTimeBehavior=convertToNull
            username: root
            password: bai5331359
            # 初始化大小，最小，最大
            initialSize: 1
            minIdle: 3
            maxActive: 20
            # 配置获取连接等待超时的时间
            maxWait: 60000
            # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
            timeBetweenEvictionRunsMillis: 60000
            # 配置一个连接在池中最小生存的时间，单位是毫秒
            minEvictableIdleTimeMillis: 30000
            validationQuery: select 'x'
            testWhileIdle: true
            testOnBorrow: false
            testOnReturn: false
            # 打开PSCache，并且指定每个连接上PSCache的大小
            poolPreparedStatements: true
            maxPoolPreparedStatementPerConnectionSize: 20
            # 配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
            filters: stat,wall,slf4j
            # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
            connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
            # 合并多个DruidDataSource的监控数据
            #useGlobalDataSourceStat: true
        
        
        #Mybatis Settings
        
        mybatis:
          #配置Mybatis typealias，Mapper XML 文件中将不再做繁琐的别名申明，一般扫描实体(包/类) 
          type-aliases-package: com.example.demo.dao
          config-location: classpath:mybatis/mybatis-config.xml
          mapper-locations: classpath:mybatis/mapper/*.xml #Server server: port: 8080 tomcat: uri-encoding: utf-8 servlet: context-path: /impact
 *  mybatis-config.xml Mybatyis设置文件
    
        <?xml version="1.0" encoding="UTF-8" ?>
        <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
        <configuration>
            <settings>
                <setting name="cacheEnabled" value="true" />  
                <setting name="useGeneratedKeys" value="true" />  
                <setting name="defaultExecutorType" value="REUSE" /> 
                <setting name="mapUnderscoreToCamelCase" value="true"/> 
                <setting name="logImpl" value="SLF4J" /> 
            </settings>
        </configuration>
 *  ExmapleDao.xml Mapper 文件
    
        <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
        <mapper namespace="com.example.demo.dao.ExmapleDao">
            <resultMap type="Lock" id="LockResult">
                <result property="schedName" column="sched_name" />
                <result property="lockName" column="lock_name" />
            </resultMap>
        
            <insert id="insertLock" parameterType="Lock">
                insert into qrtz_locks (sched_name,lock_name) values ( #{schedName},#{lockName} )
            </insert>
        
        
        
        </mapper>
 *  DB 表信息
    
        CREATE TABLE `qrtz_locks` ( `sched_name` varchar(120) NOT NULL, `lock_name` varchar(40) NOT NULL, PRIMARY KEY (`sched_name`,`lock_name`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
 *  结果  
    ![这里写图片描述][70 1]

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

## 小结 ##

*  SpringBoot整合Mybatis 一定要在启动类(DruidExmapleApplication.java)上添加 **@MapperScan(“com.example.demo.dao”)** 来扫描指定路径下的Mapper接口已将Dao层Bean注入到Spring IOC contianor中。
 *  本节中对于Lock 别名的申明我们交由Spring Scan Bean的装配来完成的，进而不用再Mybatis配置文件中做繁琐的别名申明了，一般在Application的配置文件中配置：**mybatis.type-aliases-package=com.example.demo.entity**(实体类集中的包)，即可在Mapper xml 文件中引用。

[SpringBoot_ _ _Mybatis]: https://blog.csdn.net/u012437781/article/details/78630860
[SpringBoot_ _ DataSource]: https://blog.csdn.net/u012437781/article/details/80283757
[70]: /images/20220525/e2b818acdb5948ae9dfdd5bb4829e6f8.png
[70 1]: /images/20220525/b4ecd6e384a6417e846596aff44f056f.png