dubbo source read - Configuration (c) of the attribute configuration

Sample Code

public class Provider {
    /**
     * In order to make sure multicast registry works, need to specify '-Djava.net.preferIPv4Stack=true' before
     * launch the application
     */
    public static void main(String[] args) throws Exception {
        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ProviderConfiguration.class);
        context.start();
        System.in.read();
    }

    @Configuration
    /**
     * <1>内部包含import注解 作为初始化
     * 快速入门:https://www.cnblogs.com/yichunguo/p/12122598.html
     */
    @EnableDubbo(scanBasePackages = "provider") //
    @PropertySource("classpath:dubbo-provider.properties") // <2>
    static class ProviderConfiguration {
    }
}

dubbo-provider configuration

dubbo.application.name=soa-promotion-provider
dubbo.registry.address=127.0.0.1:9080
dubbo.registry.check=false
dubbo.protocol.name=dubbo
dubbo.protocol.port=23888
dubbo.protocol.threads=500
dubbo.protocol.dispatcher=message
dubbo.provider.delay=-1
dubbo.provider.retries=false

Corresponding to the object is created inside the container after the config configuration

<1>EnableDubbo

@Target (ElementType.TYPE {}) // only play on the class 
@Retention (RetentionPolicy.RUNTIME) // retained until runtime 
@Inherited 
@Documented 
@EnableDubboConfig // <2> @Import annotation position 
@DubboComponentScan
 public @ interface {EnableDubbo
     / ** 
     * Spring subsequent annotations can obtain DubboComponentScan api get the value provided by DubboComponentScan Spring 
     * @return 
     * / 
    @AliasFor (annotation = DubboComponentScan. class , attribute = "basePackages" ) 
    String [] scanBasePackages () default { }; 

    / **  
     * DubboComponentScan annotations merger
     * @return
     */
    @AliasFor(annotation = DubboComponentScan.class, attribute = "basePackageClasses")
    Class<?>[] scanBasePackageClasses() default {};
    /**
     * DubboComponentScan的合并注解
     * @return
     */
    @AliasFor(annotation = EnableDubboConfig.class, attribute = "multiple")
    boolean multipleConfig() default true;

}

<2>EnableDubboConfig

@Target (ElementType.TYPE {}) 
@Retention (RetentionPolicy.RUNTIME) 
@Inherited 
@Documented 
@Import (DubboConfigConfigurationRegistrar. Class ) // <. 3> initialization entry point 
public @ interface EnableDubboConfig { 

    / ** 
     * supports multiple configuration 
     * dubbo = 192.168.0.1 .registrys.beaname1.address: 1111 
     * dubbo.registrys.beaname2.address = 192.168.0.1: 1111 
     * @return 
     * / 
    Boolean Multiple () default  to true ; 

}

@Import Quickstart: Links 

As can be understood as the bean is initialized spring containers will be called the @Import

DubboConfigConfigurationRegistrar

<3>DubboConfigConfigurationRegistrar

org.springframework.context.annotation.ImportBeanDefinitionRegistrar

public  class DubboConfigConfigurationRegistrar the implements ImportBeanDefinitionRegistrar { 

    / ** 
     * 
     * @param importingClassMetadata additional annotation contain information @Import annotation class 
     * @param Registry can be injected through the vessel as he bean
      * / 
    @Override 
    public  void registerBeanDefinitions (AnnotationMetadata importingClassMetadata, the BeanDefinitionRegistry Registry) { 

        / ** 
         * get EnableDubboConfig annotation information 
         * / 
        AnnotationAttributes the Attributes = AnnotationAttributes.fromMap ( 
                importingClassMetadata.getAnnotationAttributes (EnableDubboConfig.class .getName ()));
         / ** 
         * Get multiple defaults to true indicating whether a plurality of supports arranged config 
         * The 
         * / 
        Boolean multiple attributes.getBoolean = ( "multiple" );
         / ** 
         * initialize single configuration config 
         * < 4> Note @Import played such notes continue to read 
         * / 
        registerBeans (Registry, DubboConfigConfiguration.Single. class ); 

        / ** 
         * <4> If you open multiple configurations to initialize multiple configurations config 
         * dubbo.applications ddd = .beanname.id 
         * dubbo.registrys.beaname2.address = 192.168.0.1: 1111 
         * dubbo.registrys.beaname2.address = 192.168.0.1: 2222 
         * / 
        IF (Multiple) { // Since 2.6.6 https://github.com/apache/incubator-dubbo/issues/3193
            registerBeans(registry, DubboConfigConfiguration.Multiple.class);
        }
    }
}

<4>DubboConfigConfiguration

public class DubboConfigConfiguration {
    /**
     * <5>定义了单个配置 每个前缀对应的 类
     */
    @EnableDubboConfigBindings({
            @EnableDubboConfigBinding(prefix = "dubbo.application", type = ApplicationConfig.class),
            @EnableDubboConfigBinding(prefix = "dubbo.module", type = ModuleConfig.class),
            @EnableDubboConfigBinding(prefix = "dubbo.registry", type = RegistryConfig.class),
            @EnableDubboConfigBinding(prefix = "dubbo.protocol", type = ProtocolConfig.class),
            @EnableDubboConfigBinding(prefix = "dubbo.monitor", type = MonitorConfig.class),
            @EnableDubboConfigBinding(prefix = "dubbo.provider", type = ProviderConfig.class),
            @EnableDubboConfigBinding(prefix = "dubbo.consumer", type = ConsumerConfig.class)
    })
    public static class Single {

    }
    /**
     * <5>定义了多个配置每个前缀对应的类
     */
    @EnableDubboConfigBindings({
            @EnableDubboConfigBinding(prefix = "dubbo.applications", type = ApplicationConfig.class, multiple = true),
            @EnableDubboConfigBinding(prefix = "dubbo.modules", type = ModuleConfig.class, multiple = true),
            @EnableDubboConfigBinding(prefix = "dubbo.registries", type = RegistryConfig.class, multiple = true),
            @EnableDubboConfigBinding(prefix = "dubbo.protocols", type = ProtocolConfig.class, multiple = true),
            @EnableDubboConfigBinding(prefix = "dubbo.monitors", type = MonitorConfig.class, multiple = true),
            @EnableDubboConfigBinding(prefix = "dubbo.providers", type = ProviderConfig.class, multiple = true),
            @EnableDubboConfigBinding(prefix = "dubbo.consumers", type = ConsumerConfig.class, multiple = true)
    })
    public static class Multiple {

    }
}

<5>EnableDubboConfigBindings

/ ** 
 * Multiple { @link EnableDubboConfigBinding} { @link Annotation} 
 * 
 * @Since 2.5.8 
 * @see EnableDubboConfigBinding
  * / 
@Target (ElementType.TYPE {}) // annotation limit to play in place 
@Retention (RetentionPolicy. rUNTIME) // annotation retention period is reserved here to run 
@Documented // identifying javadoc recorded 
@Import (DubboConfigBindingsRegistrar. class ) examples // Note the <3> .4 registration Department will be marked with this annotation to the container so will trigger Import <. 6> @Import 
public @ interface EnableDubboConfigBindings { 

    / ** 
     * of The value of {@link EnableDubboConfigBindings}
     *
     * @return non-null
     */
    EnableDubboConfigBinding[] value();

}

DubboConfigBindingsRegistrar

<6>registerBeanDefinitions

com.alibaba.dubbo.config.spring.context.annotation.DubboConfigBindingsRegistrar#registerBeanDefinitions

    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {

        //获取EnableDubboConfigBindings注解实例
        AnnotationAttributes attributes = AnnotationAttributes.fromMap(
                importingClassMetadata.getAnnotationAttributes(EnableDubboConfigBindings.class.getName()));
        //获得values注解实例 EnableDubboConfigBinding
        AnnotationAttributes[] annotationAttributes = attributes.getAnnotationArray("value");
        DubboConfigBindingRegistrar registrar = new DubboConfigBindingRegistrar();
        registrar.setEnvironment (Environment); 
        // Loop through EnableDubboConfigBinding Configuration <4> can be acquired at respective class mapping between prefix and 
        for (AnnotationAttributes Element: annotationAttributes) {
             // < . 7> prefix and parses class mapping relationship 
            registrar.registerBeanDefinitions (Element, Registry); 

        } 
    }

DubboConfigBindingRegistrar

<7>registerBeanDefinitions

com.alibaba.dubbo.config.spring.context.annotation.DubboConfigBindingRegistrar#registerBeanDefinitions

 protected  void registerBeanDefinitions (AnnotationAttributes Attributes, the BeanDefinitionRegistry Registry) { 

        / ** * 
         * prefix obtained annotation configuration such as 
         * dubbo.application 
         * environment.resolvePlaceholders we configured to avoid change if so placeholder 
         * such as $ {applictionPrefix} .name = 
         * / 
        String prefix = environment.resolvePlaceholders (attributes.getString ( "prefix" )); 

        / ** 
         * Get prefix as the corresponding class is dubbo.application class is com.alibaba.dubbo.config.ApplicationConfig 
         * generic <extends AbstractConfig> limit class must inherit AbstractConfig 
         * / 
        Class <? the extendsAbstractConfig> = attributes.getClass the configClass ( "type" ); 

        / ** 
         * whether a plurality of configuration 
         * / 
        Boolean Multiple attributes.getBoolean = ( "Multiple" ); 

        / ** 
         * <. 8> corresponding to create the bean config 
         * / 
        registerDubboConfigBeans (prefix, the configClass, Multiple, Registry); 

    }

<8>registerDubboConfigBeans

private void registerDubboConfigBeans(String prefix,
                                          Class<? extends AbstractConfig> configClass,
                                          boolean multiple,
                                          BeanDefinitionRegistry registry) {

        //获得指定前缀的属性 如:dubbo.application.name=333  key=name value=333
        Map<String, Object> properties = getSubProperties(environment.getPropertySources(), prefix);

        if (CollectionUtils.isEmpty(properties)) {
            if (log.isDebugEnabled()) {
                log.debug("There IS NO Property class for Binding to Dubbo config [" + configClass.getName ()
                         + "] WITHIN prefix [" prefix + + "]" ); 
            } 
            return ; 
        } 
        / ** 
         * configuration profiles for false acquisition mltiple configuration id as beanName (id) 
         * If you do not get the full name of the generated class #index overlay 
         * multip is true parsing 
         * dubbo.applications.beanname1.name = ffff 
         * dubbo.applications.beanname2.namee = ffff2 
         * this time beanname1 and beanname2 will as a two-beanId 
         * / 
        the Set <String> = Multiple beanNames?  resolveMultipleBeanNames (the Properties):
                Collections.singleton (resolveSingleBeanName (the Properties, configClass, Registry)); 

        for (String beanName: beanNames) { 

            / ** 
             * here does not really initialize config object will only tell the bean definition of container for container initialization 
             * After initialization of each config attributes are null 
             * / 
            registerDubboConfigBean (the beanName, the configClass, Registry); 

            / ** 
             * <. 8> DubboConfigBindingBeanPostProcessor for initialization corresponding to the properties later injected into the configuration corresponding config 
             * / 
            registerDubboConfigBindingBeanPostProcessor (prefix, the beanName, Multiple, Registry) ; 

        } 
        // Create NamePropertyDefaultValueDubboConfigBeanCustomizer to the vessel, for use DubboConfigBindingBeanPostProcessor 
        registerDubboConfigBeanCustomizers (registry);
 
    }