Springboot常用注解及作用说明

@Configuration
@ConditionalOnClass(JestClient.class)
@EnableConfigurationProperties(ConfigBean.class)
@AutoConfigureAfter(GsonAutoConfiguration.class)
public class JestAutoConfiguration {
}

@Configuration
@ConditionalOnBean(SqlSessionFactory.class)
@EnableConfigurationProperties(PageHelperProperties.class)
@AutoConfigureAfter(MybatisAutoConfiguration.class)
public class PageHelperAutoConfiguration {
}

//使用方式
@AutoConfigureBefore(AAAA.class)
public class CCCC {
	//说明 CCCC将会在AAAA之前加载
}
@AutoConfigureAfter(AAAA.class)
public class CCCC {
	//说明 CCCC将会在AAAA之后加载
}

//使用方式
@ConfigurationProperties(prefix = "spring.elasticsearch.jest")
public class ConfigBean {
}
//仅通过@ConfigurationProperties是⽆法完成ConfigBean在spring中使⽤的
@Configuration
@EnableConfigurationProperties({ConfigBean.class}) 
public class JestAutoConfiguration {	
}

//使用方式
@ConditionalOnProperty(prefix = "email",name= "enable",havingValue = "true")
//必须yml中必须包含 prefix.enable=true 才会生效

//nacos的配置
@ConditionalOnProperty(name = "spring.cloud.nacos.config.enabled", matchIfMissing = true)

//使用方式
@Configuration
public class MainConfigOfProfile{
	//@Profile关联Yellow类，当容器环境包含该"test"，才激活此注解，Yellow这个bean才会注册到容器
	@Profile("test") 
	@Bean
	public Yellow yellow(){
		return new Yellow();
	}
}
//2.设置需要激活对应的@Profile
applicationContext.getEnvironment().setActiveProfiles("test1");