1、pom文件

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>

<groupId>org.springframework.boot</groupId>
<artifactId>waterloggingdata</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>jar</packaging>
<name>waterloggingdata</name>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.0.2.RELEASE</version>
    <relativePath />
</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>
    <!--spring-boot初始jar包开始-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <!--spring-boot初始jar包结束-->

    <!--mybatisplus相关jar包开始-->
    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
        <version>2.5.6</version>
    </dependency>
    <dependency>
        <artifactId>mybatis-plus-boot-starter</artifactId>
        <groupId>com.baomidou</groupId>
        <version>3.0.5</version>
    </dependency>
    <!--<dependency>-->
        <!--<groupId>com.baomidou</groupId>-->
        <!--<artifactId>mybatis-plus</artifactId>-->
        <!--<version>2.3</version>-->
    <!--</dependency>-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
    </dependency>
    <!--mybatisplus相关jar包结束-->

    <!--引擎模板相关jar包开始-->
    <dependency>
        <groupId>org.apache.velocity</groupId>
        <artifactId>velocity</artifactId>
        <version>1.7</version>
    </dependency>
    <dependency>
        <groupId>org.freemarker</groupId>
        <artifactId>freemarker</artifactId>
        <version>2.3.28</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-thymeleaf</artifactId>
    </dependency>
    <!--引擎模板相关jar包结束-->

    <!--热部署jar开始-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
    </dependency>
    <!--热部署jar结束-->

    <!--lombok 开始-->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <scope>provided</scope>
    </dependency>
    <!--lombok 结束-->

    <!--链接数据库相关jar包开始-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>6.0.6</version>
    </dependency>

    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
        <version>1.1.10</version>
        <optional>true</optional>
    </dependency>
    <!--链接数据库相关jar包结束-->

    <!-- oracle 开始-->
    <dependency>
        <groupId>com.oracle</groupId>
        <artifactId>ojdbc6</artifactId>
        <version>11.2.0</version>
    </dependency>
    <!-- oracle 结束-->

</dependencies>

<build>
    <resources>
        <resource>
            <directory>src/main/java</directory>
            <filtering>false</filtering>
            <includes>
                <include>**/*.xml</include>
            </includes>
        </resource>
        <!--指定资源的位置 -->
        <resource>
            <directory>src/main/resources</directory>
        </resource>
    </resources>

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

2、配置文件
如果选择druid链接池要去除druid配置；还要配置一个默认数据源（spring.datasource.dynamic.primary）

#Service Config
server.port=8912
server.tomcat.uri-encoding=UTF-8

#DRUID POOL Congif
spring.datasource.dynamic.druid.initial-size=5
spring.datasource.dynamic.druid.min-idle=5
spring.datasource.dynamic.druid.max-active=20
spring.datasource.dynamic.druid.max-wait=60000
spring.datasource.dynamic.druid.time-between-eviction-runs-millis=60000
spring.datasource.dynamic.druid.min-evictable-idle-time-millis=300000
spring.datasource.dynamic.druid.validation-query=SELECT 1 FROM DUAL 
spring.datasource.dynamic.druid.test-while-idle=true
spring.datasource.dynamic.druid.test-on-borrow=false
spring.datasource.dynamic.druid.test-on-return=false
spring.datasource.dynamic.druid.pool-prepared-statements=true
spring.datasource.dynamic.druid.max-pool-prepared-statement-per-connection-size=20


#去除druid配置
spring.autoconfigure.exclude=com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceAutoConfigure



#默认数据源
spring.datasource.dynamic.primary=mysql
#mysql数据源配置
spring.datasource.dynamic.datasource.mysql.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.dynamic.datasource.mysql.url=jdbc\:mysql\://xxxxx?useOldAliasMetadataBehavior\=true&useUnicode\=true&characterEncoding\=UTF-8&autoReconnect\=true&autoReconnectForPools\=true&failOverReadOnly\=false&connectTimeout\=0&socketTimeout\=0&allowMultiQueries\=true&useSSL\=false&serverTimezone\=Hongkong&rewriteBatchedStatements\=true
spring.datasource.dynamic.datasource.mysql.username=xxxx
spring.datasource.dynamic.datasource.mysql.password=xxxx

#oracle数据源配置
spring.datasource.dynamic.datasource.oracle.driver-class-name=oracle.jdbc.driver.OracleDriver
spring.datasource.dynamic.datasource.oracle.url=jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS_LIST= (ADDRESS=(PROTOCOL=TCP)(HOST=10.48.36.150)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME=racdb)))
spring.datasource.dynamic.datasource.oracle.username=xxxx
spring.datasource.dynamic.datasource.oracle.password=xxxx

#mybatis-plus
mybatis-plus.mapper-locations=classpath\:sqlMapperXml/*Mapper.xml
mybatis-plus.typeAliasesPackage=com.dream.team.model
mybatis-plus.global-config.id-type=2
mybatis-plus.global-config.field-strategy=2
mybatis-plus.global-config.auto-set-db-type=true
mybatis-plus.global-config.db-column-underline=true
mybatis-plus.global-config.refresh-mapper=true
mybatis-plus.configuration.map-underscore-to-camel-case=true
mybatis-plus.configuration.cache-enabled=false
mybatis-plus.configuration.jdbc-type-for-null=null
mybatis-plus.configuration.call-setters-on-nulls=true

# ELASTICSEARCH (ElasticsearchProperties)
# Elasticsearch cluster name.
spring.data.elasticsearch.cluster-name=elasticsearch
# Comma-separated list of cluster node addresses.
spring.data.elasticsearch.cluster-nodes=127.0.0.1:9300
# Whether to enable Elasticsearch repositories.
spring.data.elasticsearch.repositories.enabled=true


logging.level.root=info
logging.level.com.caody.muyi=debug
logging.path=logs/

3、数据源切换

@Service
@DS("oracle")
public class QxdmsSurfGuojiaDataHourServiceImpl extends ServiceImpl<QxdmsSurfGuojiaDataHourMapper, QxdmsSurfGuojiaDataHour> implements IQxdmsSurfGuojiaDataHourService {

}