Spring 和 Mybatis 使用不同的數(shù)據(jù)源會怎樣?

//AppConfig.java
import com.alibaba.druid.pool.DruidDataSource;import org.apache.ibatis.session.SqlSessionFactory;import org.mybatis.spring.SqlSessionFactoryBean;import org.mybatis.spring.annotation.MapperScan;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.jdbc.datasource.DataSourceTransactionManager;import org.springframework.jdbc.datasource.DriverManagerDataSource;import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.sql.DataSource;
@EnableTransactionManagement@MapperScan("com.infuq.mybatis.mapper")@ComponentScanpublic class AppConfig {

    // 數(shù)據(jù)源    @Bean    public DataSource druidDataSource() {        DruidDataSource dataSource = new DruidDataSource();        dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");        dataSource.setUrl("jdbc:mysql://localhost:3306/test_0?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true");        dataSource.setUsername("root");        dataSource.setPassword("9527");
        return dataSource;    }
    // 數(shù)據(jù)源    @Bean    public DataSource dataSource() {        DriverManagerDataSource dataSource = new DriverManagerDataSource();        dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");        dataSource.setUrl("jdbc:mysql://localhost:3306/test_1?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true");        dataSource.setUsername("root");        dataSource.setPassword("9527");
        return dataSource;    }
    // Mybatis需要一個(gè)SqlSessionFactory, 因此向容器中注入一個(gè)SqlSessionFactory    @Bean    public SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
        SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();        factoryBean.setDataSource(dataSource);        return factoryBean.getObject();
    }
    // 事務(wù)管理器, 用于事務(wù)管理    @Bean    public DataSourceTransactionManager druidTransactionManager(DataSource druidDataSource) {        return new DataSourceTransactionManager(druidDataSource);    }
}

// UserServiceImpl.java
import com.infuq.mybatis.mapper.UserMapper;import org.springframework.beans.BeansException;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;import org.springframework.transaction.annotation.Transactional;
public class UserServiceImpl implements UserService {
  @Autowired  private UserMapper userMapper;    @Transactional(transactionManager = "druidTransactionManager")  @Override  public void getList() {      userMapper.getList();  }
}

//AppConfig.java@Beanpublic DataSourceTransactionManager druidTransactionManager(DataSource druidDataSource) {    return new DataSourceTransactionManager(druidDataSource);}

@Overrideprotected void doBegin(Object transaction, TransactionDefinition definition) {  DataSourceTransactionObject txObject = (DataSourceTransactionObject) transaction;  Connection con = null;
  try {    if (!txObject.hasConnectionHolder() ||        txObject.getConnectionHolder().isSynchronizedWithTransaction()) {      // 拿到事務(wù)管理器中設(shè)置的數(shù)據(jù)源,并根據(jù)這個(gè)數(shù)據(jù)源創(chuàng)建一個(gè)數(shù)據(jù)庫連接      Connection newCon = obtainDataSource().getConnection();      txObject.setConnectionHolder(new ConnectionHolder(newCon), true);    }
    txObject.getConnectionHolder().setSynchronizedWithTransaction(true);
    con = txObject.getConnectionHolder().getConnection();
    Integer previousIsolationLevel = DataSourceUtils.prepareConnectionForTransaction(con, definition);    txObject.setPreviousIsolationLevel(previousIsolationLevel);    txObject.setReadOnly(definition.isReadOnly());

    if (con.getAutoCommit()) {      txObject.setMustRestoreAutoCommit(true);      // 開啟事務(wù)      con.setAutoCommit(false);    }
    prepareTransactionalConnection(con, definition);    txObject.getConnectionHolder().setTransactionActive(true);
    int timeout = determineTimeout(definition);    if (timeout != TransactionDefinition.TIMEOUT_DEFAULT) {      txObject.getConnectionHolder().setTimeoutInSeconds(timeout);    }
    if (txObject.isNewConnectionHolder()) {        // 將 dataSource -> connection 關(guān)系存到ThreadLocal中      TransactionSynchronizationManager.bindResource(obtainDataSource(), txObject.getConnectionHolder());    }  }
}

@Beanpublic SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
    SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();    factoryBean.setDataSource(dataSource);    return factoryBean.getObject();
}
@Beanpublic DataSourceTransactionManager druidTransactionManager(DataSource dataSource) {    return new DataSourceTransactionManager(dataSource);}