分布式事务代码展示以及相关知识分析

分布式事务： 就是涉及到两个及多个以上的数据的数据操作，本篇文章是以springboot集成
Atomikos来讲：
首先还是pom文件依赖的导入

<!--分布式事务 start-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jta-atomikos</artifactId>
        </dependency>

		<!--mybaties  依赖-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.1.1</version>
        </dependency>

        <!-- mysql驱动的jar包 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.11</version>
        </dependency>

配置文件中的内容如下：

server:
  port: 8084

spring:
  redis:
    host: localhost
    port: 6379 #redis中的端口号

mysql:
  datasource:
    test1:  #配置了两个数据源 其一叫做test1
      url: jdbc:mysql://localhost:3306/test01?useSSL=false&serverTimezone=UTC
      username: root
      password: 123456
      minPoolSize: 3
      maxPoolSize: 25
      maxLifetime: 20000
      borrowConnectionTimeout: 30
      loginTimeout: 30
      maintenanceInterval: 60
      maxIdleTime: 60
      testQuery: select 1
    test2: #另外一个叫做 test2
      url: jdbc:mysql://localhost:3306/test02?useSSL=false&serverTimezone=UTC
      username: root
      password: 123456
      minPoolSize: 3
      maxPoolSize: 25
      maxLifetime: 20000
      borrowConnectionTimeout: 30
      loginTimeout: 30
      maintenanceInterval: 60
      maxIdleTime: 60
      testQuery: select 1

第三步就是各种配置类编写：

//就是更为安全的从配置文件中获取到属性值,作用就是相当于value注解
@ConfigurationProperties(prefix = "mysql.datasource.test1")
@SpringBootConfiguration
@Data
public class DBConfig1 {
    private String url;
    private String username;
    private String password;
    private int minPoolSize;
    private int maxPoolSize;
    private int maxLifetime;
    private int borrowConnectionTimeout;
    private int loginTimeout;
    private int maintenanceInterval;
    private int maxIdleTime;
    private String testQuery;
}


@ConfigurationProperties(prefix = "mysql.datasource.test2")
@SpringBootConfiguration
@Data
public class DBConfig2 {
    private String url;
    private String username;
    private String password;
    private int minPoolSize;
    private int maxPoolSize;
    private int maxLifetime;
    private int borrowConnectionTimeout;
    private int loginTimeout;
    private int maintenanceInterval;
    private int maxIdleTime;
    private String testQuery;
}


/**
 * @Author: Jason
 * @Create: 2020/10/13  6:52
 * @Description mybaties配置类2
 */
@SpringBootConfiguration
@MapperScan(basePackages = "start.mapper1", sqlSessionTemplateRef = "sqlSessionTemplate2")
public class MybatiesConfig2 {

    //配置数据源
    @Bean(name = "dataSource2")
    public DataSource dataSource(DBConfig2 config) throws SQLException {
        MysqlXADataSource mysqlXaDataSource = new MysqlXADataSource();
        mysqlXaDataSource.setUrl(config.getUrl());
        mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
        mysqlXaDataSource.setPassword(config.getPassword());
        mysqlXaDataSource.setUser(config.getUsername());
        mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);

        //这里需要设置好atomikos数据源的属性补充
        AtomikosDataSourceBean xaDataSource = new AtomikosDataSourceBean();
        xaDataSource.setXaDataSource(mysqlXaDataSource);
        xaDataSource.setUniqueResourceName("dataSource2");

        //设置数据源的各项参数
        xaDataSource.setMinPoolSize(config.getMinPoolSize());
        xaDataSource.setMaxPoolSize(config.getMaxPoolSize());
        xaDataSource.setMaxLifetime(config.getMaxLifetime());
        xaDataSource.setBorrowConnectionTimeout(config.getBorrowConnectionTimeout());
        xaDataSource.setLoginTimeout(config.getLoginTimeout());
        xaDataSource.setMaintenanceInterval(config.getMaintenanceInterval());
        xaDataSource.setMaxIdleTime(config.getMaxIdleTime());
        xaDataSource.setTestQuery(config.getTestQuery());
        return xaDataSource;
    }

    //防止名称对应，所以需要另外起名为2
    @Bean(name = "sqlSessionFactory2")
    public SqlSessionFactory sqlSessionFactory(@Qualifier("dataSource2") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        return bean.getObject();
    }

    @Bean(name = "sqlSessionTemplate2")
    public SqlSessionTemplate sqlSessionTemplate(
            @Qualifier("sqlSessionFactory2") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}


/**
 * @Author: Jason
 * @Create: 2020/10/12  21:47
 * @Description mybaties配置类1
 */
@SpringBootConfiguration
@MapperScan(basePackages = "start.mapper2", sqlSessionTemplateRef = "sqlSessionTemplate")
public class MybatisConfig1 {

    /**
     *  配置数据源
     */
    @Primary
    @Bean(name = "dataSource")
    public DataSource dataSource(DBConfig1 config) throws SQLException{
        MysqlXADataSource mysqlXADataSource = new MysqlXADataSource();
        mysqlXADataSource.setURL(config.getUrl());
        mysqlXADataSource.setPinGlobalTxToPhysicalConnection(true);
        mysqlXADataSource.setPassword(config.getPassword());
        mysqlXADataSource.setUser(config.getUsername());
        mysqlXADataSource.setPinGlobalTxToPhysicalConnection(true);

        //设置Atomikos配置
        AtomikosDataSourceBean xaDataSource = new AtomikosDataSourceBean();
        xaDataSource.setXaDataSource(mysqlXADataSource);
        xaDataSource.setUniqueResourceName("dataSource");

        xaDataSource.setMinPoolSize(config.getMinPoolSize());
        xaDataSource.setMaxPoolSize(config.getMaxPoolSize());
        xaDataSource.setMaxLifetime(config.getMaxLifetime());
        xaDataSource.setBorrowConnectionTimeout(config.getBorrowConnectionTimeout());
        xaDataSource.setLoginTimeout(config.getLoginTimeout());
        xaDataSource.setMaintenanceInterval(config.getMaintenanceInterval());
        xaDataSource.setMaxIdleTime(config.getMaxIdleTime());
        xaDataSource.setTestQuery(config.getTestQuery());
        return xaDataSource;
    }

    @Primary        //当一个接口被多个类实现时，添加此注解说明是会优先是实现此类
    @Bean(name = "sqlSessionFactory")
    public SqlSessionFactory sqlSessionFactory(@Qualifier("dataSource") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        return bean.getObject();
    }

    @Primary
    @Bean(name = "sqlSessionTemplate")
    public SqlSessionTemplate sqlSessionTemplate(
            @Qualifier("sqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}