一,dynamic-datasource-spring-boot-starter的用途?

1,dynamic-datasource-spring-boot-starter 是一个基于springboot的快速集成多数据源的启动器

它由苞米豆团队出品

2,官方站及文档:

官方站

https://mybatis.plus/

官方代码站:

https://gitee.com/baomidou/dynamic-datasource-spring-boot-starter

官方文档站:

https://mybatis.plus/guide/dynamic-datasource.html

说明:刘宏缔的架构森林是一个专注架构的博客,地址:https://www.cnblogs.com/architectforest

对应的源码可以访问这里获取: https://github.com/liuhongdi/

说明:作者:刘宏缔 邮箱: 371125307@qq.com

二,演示项目的相关信息

1,项目的地址:

https://github.com/liuhongdi/multidruiddynamic

2,项目的功能说明:

访问两个数据库,分别打印出两个库中商品和订单的信息

3,项目的结构:如图:

三,配置文件说明

1,pom.xml

        <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--dynamic datasource begin-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>dynamic-datasource-spring-boot-starter</artifactId>
<version>3.0.0</version>
</dependency>
<!--dynamic datasource end-->
<!--druid begin-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>1.1.23</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>
<dependency>
<groupId>com.lmax</groupId>
<artifactId>disruptor</artifactId>
<version>3.4.2</version>
</dependency>
<!--druid end-->
<!--mybatis begin-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.3</version>
</dependency>
<!--mybatis end-->
<!--mysql begin-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!--mysql end-->

说明:因为给druid使用了log4j2日志,为避免冲突,

在spring-boot-starter-web中排除了spring-boot-starter-logging

2,application.properties

#error
server.error.include-stacktrace=always
#error
logging.level.org.springframework.web=trace
#name
spring.application.name = dynamic
# orderdb设置为主数据源
spring.datasource.dynamic.primary = orderdb
# orderdb数据源配置
spring.datasource.dynamic.datasource.orderdb.url = jdbc:mysql://127.0.0.1:3306/orderdb?useSSL=false&useUnicode=true&characterEncoding=UTF-8
spring.datasource.dynamic.datasource.orderdb.driver-class-name = com.mysql.cj.jdbc.Driver
spring.datasource.dynamic.datasource.orderdb.username = root
spring.datasource.dynamic.datasource.orderdb.password = lhddemo
spring.datasource.dynamic.datasource.orderdb.type= com.alibaba.druid.pool.DruidDataSource
spring.datasource.dynamic.datasource.orderdb.druid.initial-size=5
spring.datasource.dynamic.datasource.orderdb.druid.max-active=20
spring.datasource.dynamic.datasource.orderdb.druid.min-idle=5
spring.datasource.dynamic.datasource.orderdb.druid.max-wait=60000
spring.datasource.dynamic.datasource.orderdb.druid.min-evictable-idle-time-millis=300000
spring.datasource.dynamic.datasource.orderdb.druid.max-evictable-idle-time-millis=300000
spring.datasource.dynamic.datasource.orderdb.druid.time-between-eviction-runs-millis=60000
spring.datasource.dynamic.datasource.orderdb.druid.validation-query=select 1
spring.datasource.dynamic.datasource.orderdb.druid.validation-query-timeout=-1
spring.datasource.dynamic.datasource.orderdb.druid.test-on-borrow=false
spring.datasource.dynamic.datasource.orderdb.druid.test-on-return=false
spring.datasource.dynamic.datasource.orderdb.druid.test-while-idle=true
spring.datasource.dynamic.datasource.orderdb.druid.pool-prepared-statements=true
spring.datasource.dynamic.datasource.orderdb.druid.filters=stat,wall,log4j2
spring.datasource.dynamic.datasource.orderdb.druid.share-prepared-statements=true
# goodsdb数据源配置
spring.datasource.dynamic.datasource.goodsdb.url = jdbc:mysql://127.0.0.1:3306/store?useSSL=false&useUnicode=true&characterEncoding=UTF-8
spring.datasource.dynamic.datasource.goodsdb.driver-class-name = com.mysql.cj.jdbc.Driver
spring.datasource.dynamic.datasource.goodsdb.username = root
spring.datasource.dynamic.datasource.goodsdb.password = lhddemo
spring.datasource.dynamic.datasource.goodsdb.type= com.alibaba.druid.pool.DruidDataSource
spring.datasource.dynamic.datasource.goodsdb.druid.initial-size=5
spring.datasource.dynamic.datasource.goodsdb.druid.max-active=20
spring.datasource.dynamic.datasource.goodsdb.druid.min-idle=5
spring.datasource.dynamic.datasource.goodsdb.druid.max-wait=60000
spring.datasource.dynamic.datasource.goodsdb.druid.min-evictable-idle-time-millis=300000
spring.datasource.dynamic.datasource.goodsdb.druid.max-evictable-idle-time-millis=300000
spring.datasource.dynamic.datasource.goodsdb.druid.time-between-eviction-runs-millis=60000
spring.datasource.dynamic.datasource.goodsdb.druid.validation-query=select 1
spring.datasource.dynamic.datasource.goodsdb.druid.validation-query-timeout=-1
spring.datasource.dynamic.datasource.goodsdb.druid.test-on-borrow=false
spring.datasource.dynamic.datasource.goodsdb.druid.test-on-return=false
spring.datasource.dynamic.datasource.goodsdb.druid.test-while-idle=true
spring.datasource.dynamic.datasource.goodsdb.druid.pool-prepared-statements=true
spring.datasource.dynamic.datasource.goodsdb.druid.filters=stat,wall,log4j2
spring.datasource.dynamic.datasource.goodsdb.druid.share-prepared-statements=true
# 配置监控统计拦截的filters,去掉后监控界面sql无法统计,'wall'用于防火墙
#spring.datasource.druid.filters = stat,wall,log4j2
spring.datasource.druid.maxPoolPreparedStatementPerConnectionSize = 20
spring.datasource.druid.useGlobalDataSourceStat = true
spring.datasource.druid.connectionProperties = druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500 #druid sql firewall monitor
spring.datasource.druid.filter.wall.enabled=true
#druid sql monitor
spring.datasource.druid.filter.stat.enabled=true
spring.datasource.druid.filter.stat.log-slow-sql=true
spring.datasource.druid.filter.stat.slow-sql-millis=10000
spring.datasource.druid.filter.stat.merge-sql=true
#druid uri monitor
spring.datasource.druid.web-stat-filter.enabled=true
spring.datasource.druid.web-stat-filter.url-pattern=/*
spring.datasource.druid.web-stat-filter.exclusions=*.js,*.gif,*.jpg,*.bmp,*.png,*.css,*.ico,/druid/*
#druid session monitor
spring.datasource.druid.web-stat-filter.session-stat-enable=true
spring.datasource.druid.web-stat-filter.profile-enable=true
#druid spring monitor
spring.datasource.druid.aop-patterns=com.druid.*
#monintor,druid login user config
spring.datasource.druid.stat-view-servlet.enabled=true
spring.datasource.druid.stat-view-servlet.login-username=root
spring.datasource.druid.stat-view-servlet.login-password=root
# IP白名单 (没有配置或者为空,则允许所有访问)
spring.datasource.druid.stat-view-servlet.allow = 127.0.0.1,192.168.163.1
# IP黑名单 (存在共同时,deny优先于allow)
spring.datasource.druid.stat-view-servlet.deny = 192.168.10.1
#mybatis
mybatis.mapper-locations=classpath:/mapper/*Mapper.xml
mybatis.type-aliases-package=com.example.demo.mapper
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl
#log
logging.config = classpath:log4j2.xml

3,log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration status="OFF">
<appenders>
<Console name="Console" target="SYSTEM_OUT">
<!--只接受程序中DEBUG级别的日志进行处理-->
<ThresholdFilter level="DEBUG" onMatch="ACCEPT" onMismatch="DENY"/>
<PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] [%file:%line] %-5level %logger{35} - %msg %n"/>
</Console>
<!--处理INFO级别的日志,并把该日志放到logs/info.log文件中-->
<RollingFile name="RollingFileInfo" fileName="./logs/info.log"
filePattern="logs/$${date:yyyy-MM}/info-%d{yyyy-MM-dd}-%i.log.gz">
<Filters>
<ThresholdFilter level="INFO"/>
<ThresholdFilter level="WARN" onMatch="DENY" onMismatch="NEUTRAL"/>
</Filters>
<PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] [%file:%line] %-5level %logger{35} - %msg %n"/>
<Policies>
<SizeBasedTriggeringPolicy size="500 MB"/>
<TimeBasedTriggeringPolicy/>
</Policies>
</RollingFile>
<!--处理WARN级别的日志,并把该日志放到logs/warn.log文件中-->
<RollingFile name="RollingFileWarn" fileName="./logs/warn.log"
filePattern="logs/$${date:yyyy-MM}/warn-%d{yyyy-MM-dd}-%i.log.gz">
<Filters>
<ThresholdFilter level="WARN"/>
<ThresholdFilter level="ERROR" onMatch="DENY" onMismatch="NEUTRAL"/>
</Filters>
<PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] [%file:%line] %-5level %logger{35} - %msg %n"/>
<Policies>
<SizeBasedTriggeringPolicy size="500 MB"/>
<TimeBasedTriggeringPolicy/>
</Policies>
</RollingFile>
<!--处理error级别的日志,并把该日志放到logs/error.log文件中-->
<RollingFile name="RollingFileError" fileName="./logs/error.log"
filePattern="logs/$${date:yyyy-MM}/error-%d{yyyy-MM-dd}-%i.log.gz">
<ThresholdFilter level="ERROR"/>
<PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] [%file:%line] %-5level %logger{35} - %msg %n"/>
<Policies>
<SizeBasedTriggeringPolicy size="500 MB"/>
<TimeBasedTriggeringPolicy/>
</Policies>
</RollingFile>
<!--druid的日志记录追加器-->
<RollingFile name="druidSqlRollingFile" fileName="./logs/druid-sql.log"
filePattern="logs/$${date:yyyy-MM}/api-%d{yyyy-MM-dd}-%i.log.gz">
<PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] [%file:%line] %-5level %logger{35} - %msg %n"/>
<Policies>
<SizeBasedTriggeringPolicy size="500 MB"/>
<TimeBasedTriggeringPolicy/>
</Policies>
</RollingFile>
</appenders>
<loggers>
<AsyncRoot level="info">
<appender-ref ref="Console"/>
<appender-ref ref="RollingFileInfo"/>
<appender-ref ref="RollingFileWarn"/>
<appender-ref ref="RollingFileError"/>
</AsyncRoot>
<!--记录druid-sql的记录-->
<AsyncLogger name="druid.sql.Statement" level="debug" additivity="false">
<appender-ref ref="druidSqlRollingFile"/>
</AsyncLogger>
</loggers>
</configuration>

4,数据库的相关业务表:

goods表

CREATE TABLE `goods` (
`goodsId` bigint(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'id',
`goodsName` varchar(500) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL DEFAULT '' COMMENT 'name',
`subject` varchar(200) NOT NULL DEFAULT '' COMMENT '标题',
`price` decimal(15,2) NOT NULL DEFAULT '0.00' COMMENT '价格',
`stock` int(11) NOT NULL DEFAULT '0' COMMENT 'stock',
PRIMARY KEY (`goodsId`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT='商品表'

goods表中的数据:

INSERT INTO `goods` (`goodsId`, `goodsName`, `subject`, `price`, `stock`) VALUES
(3, '100分电动牙刷', '好用到让你爱上刷牙', '59.00', 96);

order表:

CREATE TABLE `orderinfo` (
`orderId` bigint(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'id',
`orderSn` varchar(100) NOT NULL DEFAULT '' COMMENT '编号',
`orderTime` timestamp NOT NULL DEFAULT '1971-01-01 00:00:01' COMMENT '下单时间',
`orderStatus` tinyint(4) NOT NULL DEFAULT '0' COMMENT '状态:0,未支付,1,已支付,2,已发货,3,已退货,4,已过期',
`userId` int(12) NOT NULL DEFAULT '0' COMMENT '用户id',
`price` decimal(10,0) NOT NULL DEFAULT '0' COMMENT '价格',
`addressId` int(12) NOT NULL DEFAULT '0' COMMENT '地址',
PRIMARY KEY (`orderId`),
UNIQUE KEY `orderSn` (`orderSn`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT='订单表'

order表中的数据:

INSERT INTO `orderinfo` (`orderId`, `orderSn`, `orderTime`, `orderStatus`, `userId`, `price`, `addressId`) VALUES
(77, '20200814171411660', '2020-08-14 09:14:12', 0, 8, '100', 0);

四,java代码说明

1,GoodsMapper.java

@Repository
@Mapper
public interface GoodsMapper {
Goods selectOneGoods(Long goodsId);
}

2,OrderMapper.java

@Repository
@Mapper
public interface OrderMapper {
Order selectOneOrder(Long orderId);
}

3,HomeController.java

@Controller
@RequestMapping("/home")
public class HomeController { @Resource
private GoodsMapper goodsMapper; @Resource
private OrderMapper orderMapper; //商品详情 参数:商品id
@GetMapping("/goodsinfo")
@ResponseBody
@DS("goodsdb")
public Goods goodsInfo(@RequestParam(value="goodsid",required = true,defaultValue = "0") Long goodsId) {
Goods goods = goodsMapper.selectOneGoods(goodsId);
return goods;
} //订单详情 参数:订单id
@GetMapping("/orderinfo")
@ResponseBody
@DS("orderdb")
public Order orderInfo(@RequestParam(value="orderid",required = true,defaultValue = "0") Long orderId) {
Order order = orderMapper.selectOneOrder(orderId);
return order;
}
}

说明:用DS注解指明要使用的数据,

dynamic-datasource官方建议把注解添加到service的方法上

4,GoodsMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.multidruiddynamic.demo.mapper.goodsdb.GoodsMapper">
<select id="selectOneGoods" parameterType="long" resultType="com.multidruiddynamic.demo.pojo.Goods">
select * from goods where goodsId=#{goodsId}
</select>
</mapper>

5,OrderMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.multidruiddynamic.demo.mapper.orderdb.OrderMapper">
<select id="selectOneOrder" parameterType="long" resultType="com.multidruiddynamic.demo.pojo.Order">
select * from orderinfo where orderId=#{orderId}
</select>
</mapper>

6,Goods.java

public class Goods {
//商品id
Long goodsId;
public Long getGoodsId() {
return this.goodsId;
}
public void setGoodsId(Long goodsId) {
this.goodsId = goodsId;
} //商品名称
private String goodsName;
public String getGoodsName() {
return this.goodsName;
}
public void setGoodsName(String goodsName) {
this.goodsName = goodsName;
} //商品标题
private String subject;
public String getSubject() {
return this.subject;
}
public void setSubject(String subject) {
this.subject = subject;
} //商品价格
private BigDecimal price;
public BigDecimal getPrice() {
return this.price;
}
public void setPrice(BigDecimal price) {
this.price = price;
} //库存
int stock;
public int getStock() {
return this.stock;
}
public void setStock(int stock) {
this.stock = stock;
} public String toString(){
return " Goods:goodsId=" + goodsId +" goodsName=" + goodsName+" subject=" + subject+" price=" + price+" stock=" + stock;
}
}

7,Order.java

//订单模型
public class Order {
//订单id
Long orderId;
public Long getOrderId() {
return this.orderId;
}
public void setOrderId(Long orderId) {
this.orderId = orderId;
} //订单编号
private String orderSn;
public String getOrderSn() {
return this.orderSn;
}
public void setOrderSn(String orderSn) {
this.orderSn = orderSn;
} //下单时间
private String orderTime;
public String getOrderTime() {
return this.orderTime;
}
public void setOrderTime(String orderTime) {
this.orderTime = orderTime;
} //订单状态
int orderStatus;
public int getOrderStatus() {
return this.orderStatus;
}
public void setOrderStatus(int orderStatus) {
this.orderStatus = orderStatus;
} //订单状态
int userId;
public int getUserId() {
return this.userId;
}
public void setUserId(int userId) {
this.userId = userId;
} //订单价格
private BigDecimal price;
public BigDecimal getPrice() {
return this.price;
}
public void setPrice(BigDecimal price) {
this.price = price;
} public String toString(){
return " Order:orderId=" + orderId +" orderSn=" + orderSn+" orderTime=" + orderTime+" orderStatus:"+orderStatus+" userId:"+userId+" price=" + price;
}
}

8,DemoApplication.java

@SpringBootApplication(exclude = DruidDataSourceAutoConfigure.class)
public class DemoApplication { public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
} }

说明:在启动类上需要排除:DruidDataSourceAutoConfigure,

否则启动时会提示找不到数据源的url

五,测试效果

1,查询商品信息,访问:

http://127.0.0.1:8080/home/goodsinfo?goodsid=3

返回:

{"goodsId":3,"goodsName":"100分电动牙刷","subject":"好用到让你爱上刷牙","price":59.00,"stock":96}

2,查询订单信息,访问:

http://127.0.0.1:8080/home/orderinfo?orderid=77

返回:

{"orderId":77,"orderSn":"20200814171411660","orderTime":"2020-08-14 17:14:12","orderStatus":0,"userId":8,"price":100}

3,查看druid管理页面中的数据源:

可以看到已连接了两个数据源

六,查看spring boot的版本:

  .   ____          _            __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.3.3.RELEASE)

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