Dubbo源码学习一

//dubbo入口publicclassDubboNamespaceHandlerextendsNamespaceHandlerSupportimplementsConfigurableSourceBeanMetadataElement {
static {
Version.checkDuplicate(DubboNamespaceHandler.class);
    }
//找到入口，解析Dubbo的相关标签的@Overridepublicvoidinit() {
//将解析好的元素的key-value信息放入到BeanDefintionMap中//registerBeanDefinitionParser(String elementName, BeanDefinitionParser parser);//this.parsers.put(elementName, parser);// DubboBeanDefinitionParser(Class<?> beanClass, boolean required),也是key-value的map形式registerBeanDefinitionParser("application", newDubboBeanDefinitionParser(ApplicationConfig.class, true));
registerBeanDefinitionParser("module", newDubboBeanDefinitionParser(ModuleConfig.class, true));
registerBeanDefinitionParser("registry", newDubboBeanDefinitionParser(RegistryConfig.class, true));
registerBeanDefinitionParser("config-center", newDubboBeanDefinitionParser(ConfigCenterBean.class, true));
registerBeanDefinitionParser("metadata-report", newDubboBeanDefinitionParser(MetadataReportConfig.class, true));
registerBeanDefinitionParser("monitor", newDubboBeanDefinitionParser(MonitorConfig.class, true));
registerBeanDefinitionParser("metrics", newDubboBeanDefinitionParser(MetricsConfig.class, true));
registerBeanDefinitionParser("ssl", newDubboBeanDefinitionParser(SslConfig.class, true));
registerBeanDefinitionParser("provider", newDubboBeanDefinitionParser(ProviderConfig.class, true));
registerBeanDefinitionParser("consumer", newDubboBeanDefinitionParser(ConsumerConfig.class, true));
registerBeanDefinitionParser("protocol", newDubboBeanDefinitionParser(ProtocolConfig.class, true));
registerBeanDefinitionParser("service", newDubboBeanDefinitionParser(ServiceBean.class, true));
registerBeanDefinitionParser("reference", newDubboBeanDefinitionParser(ReferenceBean.class, false));
registerBeanDefinitionParser("annotation", newAnnotationBeanDefinitionParser());
    }
/*** 复写NamespaceHandlerSupport的parse方法,为注解配置服务* @since 2.7.5*/@OverridepublicBeanDefinitionparse(Elementelement, ParserContextparserContext) {
BeanDefinitionRegistryregistry=parserContext.getRegistry();
//注册注解配置处理器registerAnnotationConfigProcessors(registry);
//注册上下文监听器registerApplicationListeners(registry);
//进行bena的解析BeanDefinitionbeanDefinition=super.parse(element, parserContext);
//设置资源setSource(beanDefinition);
returnbeanDefinition;
    }
/*** 将{@link ApplicationListener ApplicationListeners}注册为Spring Bean* @since 2.7.5*/privatevoidregisterApplicationListeners(BeanDefinitionRegistryregistry) {
//注册bean dubbo生命周期组件上下文监听registerBeans(registry, DubboLifecycleComponentApplicationListener.class);
//注册bean dubbo服务器上下文监听registerBeans(registry, DubboBootstrapApplicationListener.class);
    }
/***  注册注解配置处理器* @since 2.7.5*/privatevoidregisterAnnotationConfigProcessors(BeanDefinitionRegistryregistry) {
AnnotationConfigUtils.registerAnnotationConfigProcessors(registry);
    }
}

//进行刷新操作，继承父类的refresh@Overridepublicvoidrefresh() {
super.refresh();
appendEnvironmentProperties();
}
//调用父类AbstractConfig#refresh方法//进行刷新操作publicvoidrefresh() {
//拿到环境变量信息Environmentenv=ApplicationModel.getEnvironment();
try {
CompositeConfigurationcompositeConfiguration=env.getPrefixedConfiguration(this);
//循环方法，将新的value设置到方法中Method[] methods=getClass().getMethods();
for (Methodmethod : methods) {
//setter方法if (MethodUtils.isSetter(method)) {
try {
Stringvalue=StringUtils.trim(compositeConfiguration.getString(extractPropertyName(getClass(), method)));
//调用isTypeMatch（）方法以避免重复和不正确的更新，例如，//在ReferenceConfig中我们有两个“ setGeneric”方法。if (StringUtils.isNotEmpty(value) &&ClassUtils.isTypeMatch(method.getParameterTypes()[0], value)) {
//在具有指定参数的指定对象上，调用此方法对象表示的基础方法。//各个参数将自动展开以匹配原始形式参数，并且必要时对原始//参数和引用参数都进行方法调用转换。method.invoke(this, ClassUtils.convertPrimitive(method.getParameterTypes()[0], value));
                    }
                } catch (NoSuchMethodExceptione) {
logger.info("Failed to override the property "+method.getName() +" in "+this.getClass().getSimpleName() +", please make sure every property has getter/setter method provided.");
                }
//参数setter            } elseif (isParametersSetter(method)) {
Stringvalue=StringUtils.trim(compositeConfiguration.getString(extractPropertyName(getClass(), method)));
if (StringUtils.isNotEmpty(value)) {
Map<String, String>map=invokeGetParameters(getClass(), this);
map=map==null?newHashMap<>() : map;
map.putAll(convert(StringUtils.parseParameters(value), ""));
invokeSetParameters(getClass(), this, map);
                }
            }
        }
    } catch (Exceptione) {
//复写失败logger.error("Failed to override ", e);
    }
}
//添加环境变量配置信息privatevoidappendEnvironmentProperties() {
if (parameters==null) {
parameters=newHashMap<>();
    }
//通过扩展加载器进行获取适配器Set<InfraAdapter>adapters=ExtensionLoader.getExtensionLoader(InfraAdapter.class).getSupportedExtensionInstances();
if (CollectionUtils.isNotEmpty(adapters)) {
Map<String, String>inputParameters=newHashMap<>();
//包含信息：应用名称和hos以及扩展参数信息inputParameters.put(APPLICATION_KEY, getName());
inputParameters.put(HOST_KEY, getHostname());
for (InfraAdapteradapter : adapters) {
//同时将SPI的扩展参数信息信息加入Map<String, String>extraParameters=adapter.getExtraAttributes(inputParameters);
if (CollectionUtils.isNotEmptyMap(extraParameters)) {
parameters.putAll(extraParameters);
            }
        }
    }
}