springboot - 配置参数 - 《java》

@Profile(“dev”)

配置不同的环境参数

参数注入

@SpringBootApplication
@PropertySource("classpath:appSource.properties")
public class ExternConfigurationApplication {
    public static void main(String[] args) throws IOException {
        SpringApplication springApplication = new SpringApplication(ExternConfigurationApplication.class);
        // 创建Properties
        Properties properties = new Properties();
        // 通过当前类的ClassLoader
        InputStream is= ExternConfigurationApplication.class.getClassLoader()
                .getResourceAsStream("app.properties");
        // 将输入流读取成properties
        properties.load(is);
        springApplication.setDefaultProperties(properties);
        springApplication.run(args);
    }
}

@ConfigurationProperties(prefix=”user”)
@Validated
@PropertySource(“classpath:data/user.properties”)

实现一个 enable注解
ImportSelector 等于 @import + 延时

public class MyDeferredImportSelector implements DeferredImportSelector {
    @Override
    public String[] selectImports(AnnotationMetadata importingClassMetadata) {
        return new String[]{"cn.tulingxueyuan.beans.Person"};
    }
    @Override
    public Predicate<String> getExclusionFilter() {
        return null;
    }
   @Override
    public Class<? extends Group> getImportGroup() {
        // 这个返回值决定调用DeferredImportSelector.selectImports  如果null
        // 还是调用Group.selectImports
        return  MyGroup.class;
    }
    // 如果getImportGroup返回自定义Group ， 会调用自定义Group的process方法
    // 如果getImportGroup返回 null,会调用DefaultDeferredImportSelectorGroup的process方法,即调用selectImports
    // 分组利用归类，同一组的bean只影响本组的顺序
    private static class MyGroup
            implements DeferredImportSelector.Group{
        AnnotationMetadata metadata;
        @Override
        public void process(AnnotationMetadata metadata, DeferredImportSelector selector) {
            this.metadata=metadata;
        }
        @Override
        public Iterable<Entry> selectImports() {
            List<Entry> list=new ArrayList<>();
            list.add(new Entry(this.metadata,"cn.tulingxueyuan.beans.Person"));
            return  list;
        }
    }
}

@Component
public class MyImportBeanDefinitionRegistrar implements ImportBeanDefinitionRegistrar {

    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
       GenericBeanDefinition beanDefinition=new GenericBeanDefinition();
        beanDefinition.setBeanClass(Person.class);
        registry.registerBeanDefinition("person",beanDefinition);
    }

}

ImportSelector 等于 @import

@Component
public class MyImportSelector implements ImportSelector {
    public String[] selectImports(AnnotationMetadata importingClassMetadata) {
        // 可以以字符串的形式注册多个Bean
        // 字符串必须是类的完整限定名  getBean不能根据名字获取获取的， 必须要根据类型获取
        return new String[]{"cn.tulingxueyuan.beans.Person",Wife.class.getName()};
    }
}