Java基础之《mybatis-plus多数据源配置》

1、pom文件引入依赖
引入MyBatis-Plus之后请不要再次引入MyBatis以及mybatis-spring-boot-starter和MyBatis-Spring，以避免因版本差异导致的问题

		<!--引入 MyBatis-Plus 之后请不要再次引入 MyBatis 以及 mybatis-spring-boot-starter和MyBatis-Spring，以避免因版本差异导致的问题-->
		<!--<dependency>
			<groupId>org.mybatis.spring.boot</groupId>
			<artifactId>mybatis-spring-boot-starter</artifactId>
			<version>${spring-boot.mybatis}</version>
		</dependency>-->
		
		<dependency>
			<groupId>com.baomidou</groupId>
			<artifactId>mybatis-plus-boot-starter</artifactId>
			<version>${mybatis-plus.version}</version>
		</dependency>
		
		<dependency>
			<groupId>com.baomidou</groupId>
			<artifactId>mybatis-plus-annotation</artifactId>
			<version>${mybatis-plus.version}</version>
		</dependency>

2、DataSourceConfig.java
数据源

package cn.xxx.coupon.pay.config;

import javax.sql.DataSource;

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder;

@Configuration
public class DataSourceConfig {

	@Primary
	@ConfigurationProperties(prefix = "spring.datasource.druid.one")
	@Bean(name = "dsOne")
	public DataSource dsOne() {
		return DruidDataSourceBuilder.create().build();
	}

	@ConfigurationProperties(prefix = "spring.datasource.druid.two")
	@Bean(name = "dsTwo")
	public DataSource dsTwo() {
		return DruidDataSourceBuilder.create().build();
	}
	
}

3、MybatisPlusConfigOne.java
配置mybatis-plus第一个数据库的SqlSessionFactory和SqlSessionTemplate

package cn.xxx.coupon.pay.config;

import javax.sql.DataSource;

import org.apache.ibatis.logging.stdout.StdOutImpl;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.core.MybatisConfiguration;
import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;

@Configuration
@MapperScan(basePackages = "cn.xxx.coupon.pay.mapper.dsOne", sqlSessionFactoryRef = "dsOneSqlSessionFactory", sqlSessionTemplateRef = "dsOneSqlSessionTemplate")
public class MybatisPlusConfigOne {

	@Bean(name = "dsOneSqlSessionFactory")
	public SqlSessionFactory dsOneSqlSessionFactory(@Qualifier("dsOne") DataSource datasource) throws Exception {
		MybatisSqlSessionFactoryBean bean = new MybatisSqlSessionFactoryBean();
		// 设置mybatis的xml所在位置
		// bean.setMapperLocations(new
		// PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db2/*.xml"));

		// configuration配置bean
		// MybatisConfiguration configuration = new MybatisConfiguration();
		// configuration.setMapUnderscoreToCamelCase(true); //数据库字段下划线到Java的驼峰的映射，默认true
		// configuration.setCacheEnabled(true); //是否支持mybatis的二级缓存，默认true
		// 配置打印sql语句
		// configuration.setLogImpl(StdOutImpl.class);
		// 添加自定义配置
		// bean.setConfiguration(configuration);

		// 设置datasource
		bean.setDataSource(datasource);

		// 插件对象
		MybatisPlusInterceptor mybatisPlusInterceptor = new MybatisPlusInterceptor();
		// 分页插件
		mybatisPlusInterceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
		bean.setPlugins(mybatisPlusInterceptor);

		return bean.getObject();
	}

	@Bean(name = "dsOneSqlSessionTemplate")
	public SqlSessionTemplate dsOneSqlSessionTemplate(
			@Qualifier("dsOneSqlSessionFactory") SqlSessionFactory sessionFactory) {
		return new SqlSessionTemplate(sessionFactory);
	}
}

4、MybatisPlusConfigTwo.java
配置mybatis-plus第二个数据库的SqlSessionFactory和SqlSessionTemplate

package cn.xxx.coupon.pay.config;

import javax.sql.DataSource;

import org.apache.ibatis.logging.stdout.StdOutImpl;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.baomidou.mybatisplus.annotation.DbType;
import com.baomidou.mybatisplus.core.MybatisConfiguration;
import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;

@Configuration
@MapperScan(basePackages = "cn.xxx.coupon.pay.mapper.dsTwo", sqlSessionFactoryRef = "dsTwoSqlSessionFactory", sqlSessionTemplateRef = "dsTwoSqlSessionTemplate")
public class MybatisPlusConfigTwo {

	@Bean(name = "dsTwoSqlSessionFactory")
	public SqlSessionFactory dsTwoSqlSessionFactory(@Qualifier("dsTwo") DataSource datasource) throws Exception {
		MybatisSqlSessionFactoryBean bean = new MybatisSqlSessionFactoryBean();
		// 设置mybatis的xml所在位置
		// bean.setMapperLocations(new
		// PathMatchingResourcePatternResolver().getResources("classpath*:mapper/db2/*.xml"));

		// configuration配置bean
		// MybatisConfiguration configuration = new MybatisConfiguration();
		// configuration.setMapUnderscoreToCamelCase(true); //数据库字段下划线到Java的驼峰的映射，默认true
		// configuration.setCacheEnabled(true); //是否支持mybatis的二级缓存，默认true
		// 配置打印sql语句
		// configuration.setLogImpl(StdOutImpl.class);
		// 添加自定义配置
		// bean.setConfiguration(configuration);

		// 设置datasource
		bean.setDataSource(datasource);

		// 插件对象
		MybatisPlusInterceptor mybatisPlusInterceptor = new MybatisPlusInterceptor();
		// 分页插件
		mybatisPlusInterceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
		bean.setPlugins(mybatisPlusInterceptor);

		return bean.getObject();
	}

	@Bean(name = "dsTwoSqlSessionTemplate")
	public SqlSessionTemplate dsTwoSqlSessionTemplate(
			@Qualifier("dsTwoSqlSessionFactory") SqlSessionFactory sessionFactory) {
		return new SqlSessionTemplate(sessionFactory);
	}
}

5、@MapperScan和dao层@Mapper二选一

6、定义接口类BranchInfoMapper.java

package cn.xxx.coupon.pay.mapper.dsTwo;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;

import cn.xxx.coupon.pay.dto.commodity.BranchInfo;

public interface BranchInfoMapper extends BaseMapper<BranchInfo> {

}

7、测试代码MybatisPlusTest.java

package cn.xxx.coupon.pay.test.coupon;

import java.util.List;

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;

import cn.xxx.coupon.pay.PreCouponPayApplication;
import cn.xxx.coupon.pay.dto.commodity.BranchInfo;
import cn.xxx.coupon.pay.mapper.dsTwo.BranchInfoMapper;

@SpringBootTest(classes = PreCouponPayApplication.class)
public class MybatisPlusTest {

	@Autowired
	private BranchInfoMapper branchInfoMapper;

	@Test
	public void testSelectList() {
		System.out.println(("----- selectAll method test ------"));
		List<BranchInfo> branchInfos = branchInfoMapper.selectList(null);
		branchInfos.forEach(System.out::println);
	}

	@Test
	public void testSelectOne() {
		System.out.println(("----- selectOne method test ------"));
		QueryWrapper<BranchInfo> queryWrapper = new QueryWrapper<>();
		queryWrapper.eq("storecode", "012999");
		queryWrapper.eq("issue_id", "80501");
		BranchInfo branchInfo = branchInfoMapper.selectOne(queryWrapper);
		System.out.println(branchInfo);
	}

	@Test
	public void testSelectPage() {
		QueryWrapper<BranchInfo> queryWrapper = new QueryWrapper<>();
		Page<BranchInfo> page = new Page<>(2, 30);
		Page<BranchInfo> branchInfoPage = branchInfoMapper.selectPage(page, queryWrapper);
		System.out.println("当前页：" + branchInfoPage.getCurrent());
		System.out.println("每页记录数：" + branchInfoPage.getSize());
		System.out.println("总记录数：" + branchInfoPage.getTotal());
		System.out.println("总页数：" + branchInfoPage.getPages());
		List<BranchInfo> branchInfoList = branchInfoPage.getRecords();
		branchInfoList.forEach(System.out::println);
	}
}

8、问题1：启动日志会打印两遍mybatis-plus的logo

 _ _   |_  _ _|_. ___ _ |    _ 
| | |\/|_)(_| | |_\  |_)||_|_\ 
     /               |         
                        3.5.5 
 _ _   |_  _ _|_. ___ _ |    _ 
| | |\/|_)(_| | |_\  |_)||_|_\ 
     /               |         
                        3.5.5 

9、问题2：eclipse里mybatis-plus自动提示显示中文乱码
Window -> Preferences -> General -> Workspace，找到Text file encoding，设置为UTF-8，保存重启eclipse