資料來源程式碼：

            第一個讀取配置檔案程式碼：

package com.datasource;

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;


@Configuration // 註冊到springboot容器中
@MapperScan(basePackages = "com.bdqn.dao", sqlSessionFactoryRef = "test1SqlSessionFactory")
public class TestDatasource01 {

    /**
     *
     * @methodDesc: 功能描述:(配置test1資料庫)
     *
     */
    @Bean(name = "test1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test1")
   // @Primary//自動裝配時當出現多個Bean候選者時，被註解為@Primary的Bean將作為首選者，否則將丟擲異常
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    /**
     *
     * @methodDesc: 功能描述:(test1 sql會話工廠)
    */
    @Bean(name = "test1SqlSessionFactory")
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // bean.setMapperLocations(
        // new
        // PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
        return bean.getObject();
    }

    /**
     *
     * @methodDesc: 功能描述:(test1 事物管理)
     *
     */
    @Bean(name = "test1TransactionManager")
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test1SqlSessionTemplate")
    public SqlSessionTemplate testSqlSessionTemplate(
            @Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

}

 

  第二個讀取配置檔案程式碼：

package com.datasource;

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;


@Configuration // 註冊到springboot容器中
@MapperScan(basePackages = "com.bdqn01.dao", sqlSessionFactoryRef = "test2SqlSessionFactory")
public class TestDatasource02 {
    /**
     *
     * @methodDesc: 功能描述:(配置test2資料庫)
     */
    @Bean(name = "test2DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test2")
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    /**
     *
     * @methodDesc: 功能描述:(test2 sql會話工廠)

     */
    @Bean(name = "test2SqlSessionFactory")
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // bean.setMapperLocations(
        // new
        // PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test2/*.xml"));
        return bean.getObject();
    }

    /**
     *
     * @methodDesc: 功能描述:(test2 事物管理)
     */
    @Bean(name = "test2TransactionManager")
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test2DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test2SqlSessionTemplate")
    public SqlSessionTemplate testSqlSessionTemplate(
            @Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

 

啟動報錯資訊：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: At least one JPA metamodel must be present!
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1702) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:579) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:501) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:741) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243) [spring-boot-2.0.1.RELEASE.jar:2.0.1.RELEASE]
	at com.start.main(start.java:11) [classes/:na]
Caused by: java.lang.IllegalArgumentException: At least one JPA metamodel must be present!
	at org.springframework.util.Assert.notEmpty(Assert.java:450) ~[spring-core-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.data.jpa.mapping.JpaMetamodelMappingContext.<init>(JpaMetamodelMappingContext.java:54) ~[spring-data-jpa-2.0.6.RELEASE.jar:2.0.6.RELEASE]
	at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:88) ~[spring-data-jpa-2.0.6.RELEASE.jar:2.0.6.RELEASE]
	at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:43) ~[spring-data-jpa-2.0.6.RELEASE.jar:2.0.6.RELEASE]
	at org.springframework.beans.factory.config.AbstractFactoryBean.afterPropertiesSet(AbstractFactoryBean.java:141) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1761) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1698) ~[spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
	... 16 common frames omitted


Process finished with exit code 1
 

原因沒有指定主資料來源

    第一個資料來源程式碼修改如下

package com.datasource;

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;


@Configuration // 註冊到springboot容器中
@MapperScan(basePackages = "com.bdqn.dao", sqlSessionFactoryRef = "test1SqlSessionFactory")
public class TestDatasource01 {

    /**
     *
     * @methodDesc: 功能描述:(配置test1資料庫)
     *
     */
    @Bean(name = "test1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test1")
    @Primary//自動裝配時當出現多個Bean候選者時，被註解為@Primary的Bean將作為首選者，否則將丟擲異常
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    /**
     *
     * @methodDesc: 功能描述:(test1 sql會話工廠)
    */
    @Bean(name = "test1SqlSessionFactory")
    @Primary//自動裝配時當出現多個Bean候選者時，被註解為@Primary的Bean將作為首選者，否則將丟擲異常
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // bean.setMapperLocations(
        // new
        // PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
        return bean.getObject();
    }

    /**
     *
     * @methodDesc: 功能描述:(test1 事物管理)
     *
     */
    @Bean(name = "test1TransactionManager")
   @Primary//自動裝配時當出現多個Bean候選者時，被註解為@Primary的Bean將作為首選者，否則將丟擲異常
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test1SqlSessionTemplate")
    @Primary//自動裝配時當出現多個Bean候選者時，被註解為@Primary的Bean將作為首選者，否則將丟擲異常
    public SqlSessionTemplate testSqlSessionTemplate(
            @Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

}

&nb