注解
1：<!-- <context:property-placeholder location="classpath:jdbc.properties"/> -->
<!-- <bean id="propertyPlaceholderConfigurer" class="org.springframework,beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<list>
<value>jdbc.properties<value/>
</list>
</property>
</bean> -->2:@SpringBootApplication
br/>2:@SpringBootApplication
br/>3:@FeignClient的调用逻辑跟java动态代理思想很接近
