maven:

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
 

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies
 
>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <
 
artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.0-beta</version>
        </dependency>
        <dependency>
            <groupId>io.shardingjdbc</groupId>
            <artifactId>sharding-jdbc-core</artifactId>
            <version>2.0.3</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>

    </build>

yml:

mybatis-plus:
#  mapper-locations: classpath*:/mapper/*.xml
  global-config:
    db-config:
      column-underline: true
#shardingjdbc配置      
sharding:
  jdbc:
    data-sources:
     ###配置第一個從數據庫 名稱隨便起
      ds_slave_0:
        password: root
        jdbc-url: jdbc:mysql://192.168.91.9:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=true
        driver-class-name: com.mysql.jdbc.Driver
        username: root
      ###主數據庫配置   名稱隨便起
      ds_master:
        password: root
        jdbc-url: jdbc:mysql://192.168.91.8:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=true
        driver-class-name: com.mysql.jdbc.Driver
        username: root
    ###配置讀寫分離    
    master-slave-rule:
    ###配置從庫選擇策略，提供輪詢與隨機，這裏選擇用輪詢 如果從做了集群 查詢時候做輪訓查詢
      load-balance-algorithm-type: round_robin
      ####指定從數據庫 如果多個從 用逗號隔開
      slave-data-source-names: ds_slave_0
      name: ds_ms
      ####指定主數據庫
      master-data-source-name: ds_master

config配置：

import java.sql.SQLException;
import java.util.Map;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import com.google.common.collect.Maps;

import io.shardingjdbc.core.api.MasterSlaveDataSourceFactory;
import lombok.extern.log4j.Log4j2;

@Configuration
@EnableConfigurationProperties(ShardingMasterSlaveConfig.class)
@Log4j2
// 讀取ds_master主數據源和讀寫分離配置
@ConditionalOnProperty({ "sharding.jdbc.data-sources.ds_master.jdbc-url",
        "sharding.jdbc.master-slave-rule.master-data-source-name" })
public class ShardingDataSourceConfig {

    @Autowired
    private ShardingMasterSlaveConfig shardingMasterSlaveConfig;

    @Bean
    public DataSource masterSlaveDataSource() throws SQLException {
        final Map<String, DataSource> dataSourceMap = Maps.newHashMap();
        dataSourceMap.putAll(shardingMasterSlaveConfig.getDataSources());
        final Map<String, Object> newHashMap = Maps.newHashMap();
        // 創建 MasterSlave數據源
        DataSource dataSource = MasterSlaveDataSourceFactory.createDataSource(dataSourceMap,
                shardingMasterSlaveConfig.getMasterSlaveRule(), newHashMap);
        log.info("masterSlaveDataSource config complete");
        return dataSource;
    }

}

import java.util.HashMap;
import java.util.Map;

import org.springframework.boot.context.properties.ConfigurationProperties;

import com.zaxxer.hikari.HikariDataSource;

import io.shardingjdbc.core.api.config.MasterSlaveRuleConfiguration;
import lombok.Data;

@Data      //表示讀取本底配置文件 前綴sharding.jdbc
@ConfigurationProperties(prefix = "sharding.jdbc")
public class ShardingMasterSlaveConfig {

    // 存放本地多個數據源   最終放在map集合中   key為yml配置的 ds_slave_0
    private Map<String, HikariDataSource> dataSources = new HashMap<>();

    private MasterSlaveRuleConfiguration masterSlaveRule;
}

上面為核心代碼

下面是輔助的：

Controller:

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.mayikt.entity.UserEntity;
import com.mayikt.service.UserService;

@RestController
public class UserController {

    @Autowired
    private UserService userService;

    @RequestMapping("/findUser")
    public List<UserEntity> findUser() {
        return userService.findUser();
    }

    @RequestMapping("/insertUser")
    public String insertUser(String userName) {
        return userService.insertUser(userName) > 0 ? "success" : "fail";
    }

}

entity:

public class UserEntity {

    private String userName;

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

}

service:

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.mayikt.entity.UserEntity;
import com.mayikt.mapper.UserMapper;

@Service
public class UserService {
    @Autowired
    private UserMapper userMapper;

    // 使用讀的數據源
    public List<UserEntity> findUser() {
        return userMapper.findUser();
    }

    // 使用寫的數據源
    public int insertUser(String userName) {
        return userMapper.insertUser(userName);
    }

}

mapper：

import java.util.List;

import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

import com.mayikt.entity.UserEntity;

public interface UserMapper {
    @Select("SELECT * FROM  user_info ")
    public List<UserEntity> findUser();

    @Insert("insert into user_info values (#{userName}); ")
    public int insertUser(@Param("userName") String userName);
}

啟動類：

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.toov5.mapper")
public class AppMbatis {
    public static void main(String[] args) {

        SpringApplication.run(AppMbatis.class, args);
    }
}

SpringBoot2.0整合Sharding-Jdbc