rpc框架dubbo-server（v2.6.3） 源码阅读
额，dubbo的前世今生咱就不说了，有用的人都知道。（最新版本已更名 incubator-dubbo，预计版本3.0，不过咱们就先不掺和别人的开发过程了，以v2.6.3为蓝本）
首先，是工作需要，用到了dubbo用于微服务化各系统。所以，总体来说，是被动学习。
也就是先有了做，依葫芦画瓢，然后才来理解为什么！
当然，工作需要也不能全部不知道，自然是去官网看看有什么文档，看下其工作原理，可能出现的问题。以及在工作中解决问题用到的办法。总之，已经懂得七七八八了，但是，我们需要一个深度的学习。接下来就来走走看看！
抛个砖：dubbo提供者服务示例, 其结构是这样的！
dubbo://192.168.11.6:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&dubbo=2.0.2&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=12720&side=provider×tamp=1534902103892
拿来一个官网可以运行起来的实例，让代码跑起来：
// 提供者:
public class Provider {
public static void main(String[] args) throws Exception {
//Prevent to get IPV6 address,this way only work in debug mode
//But you can pass use -Djava.net.preferIPv4Stack=true,then it work well whether in debug mode or not
System.setProperty("java.net.preferIPv4Stack", "true");
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/dubbo-demo-provider.xml"});
context.start();
// 这个比较巧妙, 只需停留在当前点，不按下enter键，服务就会一直存在，等待消费者连接，而且无需真正提供一个监听服务
System.in.read(); // press any key to exit
}
}
// 消费者:
public class Consumer {
public static void main(String[] args) {
//Prevent to get IPV6 address,this way only work in debug mode
//But you can pass use -Djava.net.preferIPv4Stack=true,then it work well whether in debug mode or not
System.setProperty("java.net.preferIPv4Stack", "true");
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]{"META-INF/spring/dubbo-demo-consumer.xml"});
context.start();
DemoService demoService = (DemoService) context.getBean("demoService"); // get remote service proxy
String hello = demoService.sayHello("world"); // call remote method, 调用远程服务和本地服务一样，这是其优势所在
System.out.println(hello); // get result
}
}
}
// xml 配置，因为使用组播协议，所以demo拿来就可以运行
// 配置很简单，主要说明下这里使用组播地址的好处。 组播是个很好的概念，可以使网络更快，也更方便开发，可以参考下: https://www.cnblogs.com/yougewe/articles/9516786.html
provider:
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xmlns="http://www.springframework.org/schema/beans"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
<!-- provider's application name, used for tracing dependency relationship -->
<dubbo:application name="demo-provider"/>
<!-- use multicast registry center to export service -->
<dubbo:registry address="multicast://224.5.6.7:1234"/>
<!-- use dubbo protocol to export service on port 20880 -->
<dubbo:protocol name="dubbo" port="20880"/>
<!-- service implementation, as same as regular local bean -->
<bean id="demoService" class="com.alibaba.dubbo.demo.provider.DemoServiceImpl"/>
<!-- declare the service interface to be exported -->
<dubbo:service interface="com.alibaba.dubbo.demo.DemoService" ref="demoService"/>
</beans>
consumer:
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:dubbo="http://dubbo.apache.org/schema/dubbo"
xmlns="http://www.springframework.org/schema/beans"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
http://dubbo.apache.org/schema/dubbo http://dubbo.apache.org/schema/dubbo/dubbo.xsd">
<!-- consumer's application name, used for tracing dependency relationship (not a matching criterion),
don't set it same as provider -->
<dubbo:application name="demo-consumer"/>
<!-- use multicast registry center to discover service -->
<dubbo:registry address="multicast://224.5.6.7:1234"/>
<!-- generate proxy for the remote service, then demoService can be used in the same way as the
local regular interface -->
<dubbo:reference id="demoService" check="false" interface="com.alibaba.dubbo.demo.DemoService"/>
</beans>
View Code
下面来讲讲其大概加载过程吧！！
// 由spring加载上下文，并到publishEvent上时，调用dubbo的event，dubbo开始介入
// spring 加载 Context
public ClassPathXmlApplicationContext(String[] configLocations, boolean refresh, ApplicationContext parent)
throws BeansException {
super(parent);
setConfigLocations(configLocations);
if (refresh) {
// 加载核心代码
refresh();
}
}
// spring 最核心的加载代码结构如下，在 最后一步加载 dubbo
@Override
public void refresh() throws BeansException, IllegalStateException {
synchronized (this.startupShutdownMonitor) {
// Prepare this context for refreshing.
prepareRefresh();
// Tell the subclass to refresh the internal bean factory.
ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();
// Prepare the bean factory for use in this context.
prepareBeanFactory(beanFactory);
try {
// Allows post-processing of the bean factory in context subclasses.
postProcessBeanFactory(beanFactory);
// Invoke factory processors registered as beans in the context.
invokeBeanFactoryPostProcessors(beanFactory);
// Register bean processors that intercept bean creation.
registerBeanPostProcessors(beanFactory);
// Initialize message source for this context.
initMessageSource();
// Initialize event multicaster for this context.
initApplicationEventMulticaster();
// Initialize other special beans in specific context subclasses.
onRefresh();
// Check for listener beans and register them.
registerListeners();
// 完成bean的加载初始化，进行bean的创建
// Instantiate all remaining (non-lazy-init) singletons.
finishBeanFactoryInitialization(beanFactory);
// 在此处使用publishEvent,加载dubbo服务
// Last step: publish corresponding event.
finishRefresh();
}
catch (BeansException ex) {
// 如果初始化异常，则先销毁各种bean，以回收内存，清理线程等
if (logger.isWarnEnabled()) {
logger.warn("Exception encountered during context initialization - " +
"cancelling refresh attempt: " + ex);
}
// Destroy already created singletons to avoid dangling resources.
destroyBeans();
// Reset 'active' flag.
cancelRefresh(ex);
// Propagate exception to caller.
throw ex;
}
finally {
// Reset common introspection caches in Spring's core, since we
// might not ever need metadata for singleton beans anymore...
resetCommonCaches();
}
}
}
// 进行bean的创建
// DefaultListableBeanFactory.preInstantiateSingletons() -> AbstractBeanFactory.doGetBean() -> DefaultSgetSingletonBeanFactory.getSingleton -> AbstractBeanFactory.createBean(),
// DefaultListableBeanFactory.registerBeanDefinition() 进行bean注册
// 会有5个beanName,由DubboBeanDefinitionParser.parse()创建，demo-provider, dubbo, com.alibaba.demo.DemoService, com.alibaba.dubbo.config.RegistryConfig, demoService
@Override
protected Object createBean(String beanName, RootBeanDefinition mbd, Object[] args) throws BeanCreationException {
if (logger.isDebugEnabled()) {
logger.debug("Creating instance of bean '" + beanName + "'");
}
RootBeanDefinition mbdToUse = mbd;
// Make sure bean class is actually resolved at this point, and
// clone the bean definition in case of a dynamically resolved Class
// which cannot be stored in the shared merged bean definition.
Class<?> resolvedClass = resolveBeanClass(mbd, beanName);
if (resolvedClass != null && !mbd.hasBeanClass() && mbd.getBeanClassName() != null) {
mbdToUse = new RootBeanDefinition(mbd);
mbdToUse.setBeanClass(resolvedClass);
}
// Prepare method overrides.
try {
mbdToUse.prepareMethodOverrides();
}
catch (BeanDefinitionValidationException ex) {
throw new BeanDefinitionStoreException(mbdToUse.getResourceDescription(),
beanName, "Validation of method overrides failed", ex);
}
try {
// Give BeanPostProcessors a chance to return a proxy instead of the target bean instance.
Object bean = resolveBeforeInstantiation(beanName, mbdToUse);
if (bean != null) {
return bean;
}
}
catch (Throwable ex) {
throw new BeanCreationException(mbdToUse.getResourceDescription(), beanName,
"BeanPostProcessor before instantiation of bean failed", ex);
}
Object beanInstance = doCreateBean(beanName, mbdToUse, args);
if (logger.isDebugEnabled()) {
logger.debug("Finished creating instance of bean '" + beanName + "'");
}
return beanInstance;
}
// spring
// ApplicationContextAwareProcessor.invokeAwareInterfaces，会进行类的默认方法初始化，此处会加载ServiceBean.setApplication初始化方法
private void invokeAwareInterfaces(Object bean) {
if (bean instanceof Aware) {
if (bean instanceof EnvironmentAware) {
((EnvironmentAware) bean).setEnvironment(this.applicationContext.getEnvironment());
}
if (bean instanceof EmbeddedValueResolverAware) {
((EmbeddedValueResolverAware) bean).setEmbeddedValueResolver(this.embeddedValueResolver);
}
if (bean instanceof ResourceLoaderAware) {
((ResourceLoaderAware) bean).setResourceLoader(this.applicationContext);
}
if (bean instanceof ApplicationEventPublisherAware) {
((ApplicationEventPublisherAware) bean).setApplicationEventPublisher(this.applicationContext);
}
if (bean instanceof MessageSourceAware) {
((MessageSourceAware) bean).setMessageSource(this.applicationContext);
}
if (bean instanceof ApplicationContextAware) {
((ApplicationContextAware) bean).setApplicationContext(this.applicationContext);
}
}
}
// 初始化类时，会调用ServiceBean.setApplication
@Override
public void setApplicationContext(ApplicationContext applicationContext) {
this.applicationContext = applicationContext;
SpringExtensionFactory.addApplicationContext(applicationContext);
if (applicationContext != null) {
SPRING_CONTEXT = applicationContext;
try {
Method method = applicationContext.getClass().getMethod("addApplicationListener", new Class<?>[]{ApplicationListener.class}); // backward compatibility to spring 2.0.1
method.invoke(applicationContext, new Object[]{this});
supportedApplicationListener = true;
} catch (Throwable t) {
if (applicationContext instanceof AbstractApplicationContext) {
try {
Method method = AbstractApplicationContext.class.getDeclaredMethod("addListener", new Class<?>[]{ApplicationListener.class}); // backward compatibility to spring 2.0.1
if (!method.isAccessible()) {
method.setAccessible(true);
}
method.invoke(applicationContext, new Object[]{this});
supportedApplicationListener = true;
} catch (Throwable t2) {
}
}
}
}
}
// 添加配置属性,138+
// Root bean: class [com.alibaba.dubbo.config.spring.ServiceBean]
// <bean id="demoService" class="com.alibaba.dubbo.demo.provider.DemoServiceImpl"/> 解析该句里加载dubbo服务
protected static void appendProperties(AbstractConfig config) {
if (config == null) {
return;
}
String prefix = "dubbo." + getTagName(config.getClass()) + ".";
Method[] methods = config.getClass().getMethods();
for (Method method : methods) {
try {
String name = method.getName();
if (name.length() > 3 && name.startsWith("set") && Modifier.isPublic(method.getModifiers())
&& method.getParameterTypes().length == 1 && isPrimitive(method.getParameterTypes()[0])) {
String property = StringUtils.camelToSplitName(name.substring(3, 4).toLowerCase() + name.substring(4), ".");
String value = null;
if (config.getId() != null && config.getId().length() > 0) {
String pn = prefix + config.getId() + "." + property;
value = System.getProperty(pn);
if (!StringUtils.isBlank(value)) {
logger.info("Use System Property " + pn + " to config dubbo");
}
}
if (value == null || value.length() == 0) {
String pn = prefix + property;
value = System.getProperty(pn);
if (!StringUtils.isBlank(value)) {
logger.info("Use System Property " + pn + " to config dubbo");
}
}
if (value == null || value.length() == 0) {
Method getter;
try {
getter = config.getClass().getMethod("get" + name.substring(3));
} catch (NoSuchMethodException e) {
try {
getter = config.getClass().getMethod("is" + name.substring(3));
} catch (NoSuchMethodException e2) {
getter = null;
}
}
if (getter != null) {
if (getter.invoke(config) == null) {
if (config.getId() != null && config.getId().length() > 0) {
value = ConfigUtils.getProperty(prefix + config.getId() + "." + property);
}
if (value == null || value.length() == 0) {
value = ConfigUtils.getProperty(prefix + property);
}
if (value == null || value.length() == 0) {
String legacyKey = legacyProperties.get(prefix + property);
if (legacyKey != null && legacyKey.length() > 0) {
value = convertLegacyValue(legacyKey, ConfigUtils.getProperty(legacyKey));
}
}
}
}
}
if (value != null && value.length() > 0) {
method.invoke(config, convertPrimitive(method.getParameterTypes()[0], value));
}
}
} catch (Exception e) {
logger.error(e.getMessage(), e);
}
}
}
// AbstractAutowireCapableBeanFactory.invokeInitMethods()
@Override
@SuppressWarnings({"unchecked", "deprecation"})
public void afterPropertiesSet() throws Exception {
if (getProvider() == null) {
Map<String, ProviderConfig> providerConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ProviderConfig.class, false, false);
if (providerConfigMap != null && providerConfigMap.size() > 0) {
Map<String, ProtocolConfig> protocolConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ProtocolConfig.class, false, false);
if ((protocolConfigMap == null || protocolConfigMap.size() == 0)
&& providerConfigMap.size() > 1) { // backward compatibility
List<ProviderConfig> providerConfigs = new ArrayList<ProviderConfig>();
for (ProviderConfig config : providerConfigMap.values()) {
if (config.isDefault() != null && config.isDefault().booleanValue()) {
providerConfigs.add(config);
}
}
if (!providerConfigs.isEmpty()) {
setProviders(providerConfigs);
}
} else {
ProviderConfig providerConfig = null;
for (ProviderConfig config : providerConfigMap.values()) {
if (config.isDefault() == null || config.isDefault().booleanValue()) {
if (providerConfig != null) {
throw new IllegalStateException("Duplicate provider configs: " + providerConfig + " and " + config);
}
providerConfig = config;
}
}
if (providerConfig != null) {
setProvider(providerConfig);
}
}
}
}
if (getApplication() == null
&& (getProvider() == null || getProvider().getApplication() == null)) {
Map<String, ApplicationConfig> applicationConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ApplicationConfig.class, false, false);
if (applicationConfigMap != null && applicationConfigMap.size() > 0) {
ApplicationConfig applicationConfig = null;
for (ApplicationConfig config : applicationConfigMap.values()) {
if (config.isDefault() == null || config.isDefault().booleanValue()) {
if (applicationConfig != null) {
throw new IllegalStateException("Duplicate application configs: " + applicationConfig + " and " + config);
}
applicationConfig = config;
}
}
if (applicationConfig != null) {
setApplication(applicationConfig);
}
}
}
if (getModule() == null
&& (getProvider() == null || getProvider().getModule() == null)) {
Map<String, ModuleConfig> moduleConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ModuleConfig.class, false, false);
if (moduleConfigMap != null && moduleConfigMap.size() > 0) {
ModuleConfig moduleConfig = null;
for (ModuleConfig config : moduleConfigMap.values()) {
if (config.isDefault() == null || config.isDefault().booleanValue()) {
if (moduleConfig != null) {
throw new IllegalStateException("Duplicate module configs: " + moduleConfig + " and " + config);
}
moduleConfig = config;
}
}
if (moduleConfig != null) {
setModule(moduleConfig);
}
}
}
if ((getRegistries() == null || getRegistries().isEmpty())
&& (getProvider() == null || getProvider().getRegistries() == null || getProvider().getRegistries().isEmpty())
&& (getApplication() == null || getApplication().getRegistries() == null || getApplication().getRegistries().isEmpty())) {
Map<String, RegistryConfig> registryConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, RegistryConfig.class, false, false);
if (registryConfigMap != null && registryConfigMap.size() > 0) {
List<RegistryConfig> registryConfigs = new ArrayList<RegistryConfig>();
for (RegistryConfig config : registryConfigMap.values()) {
if (config.isDefault() == null || config.isDefault().booleanValue()) {
registryConfigs.add(config);
}
}
if (registryConfigs != null && !registryConfigs.isEmpty()) {
super.setRegistries(registryConfigs);
}
}
}
if (getMonitor() == null
&& (getProvider() == null || getProvider().getMonitor() == null)
&& (getApplication() == null || getApplication().getMonitor() == null)) {
Map<String, MonitorConfig> monitorConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, MonitorConfig.class, false, false);
if (monitorConfigMap != null && monitorConfigMap.size() > 0) {
MonitorConfig monitorConfig = null;
for (MonitorConfig config : monitorConfigMap.values()) {
if (config.isDefault() == null || config.isDefault().booleanValue()) {
if (monitorConfig != null) {
throw new IllegalStateException("Duplicate monitor configs: " + monitorConfig + " and " + config);
}
monitorConfig = config;
}
}
if (monitorConfig != null) {
setMonitor(monitorConfig);
}
}
}
if ((getProtocols() == null || getProtocols().isEmpty())
&& (getProvider() == null || getProvider().getProtocols() == null || getProvider().getProtocols().isEmpty())) {
Map<String, ProtocolConfig> protocolConfigMap = applicationContext == null ? null : BeanFactoryUtils.beansOfTypeIncludingAncestors(applicationContext, ProtocolConfig.class, false, false);
if (protocolConfigMap != null && protocolConfigMap.size() > 0) {
List<ProtocolConfig> protocolConfigs = new ArrayList<ProtocolConfig>();
for (ProtocolConfig config : protocolConfigMap.values()) {
if (config.isDefault() == null || config.isDefault().booleanValue()) {
protocolConfigs.add(config);
}
}
if (protocolConfigs != null && !protocolConfigs.isEmpty()) {
super.setProtocols(protocolConfigs);
}
}
}
if (getPath() == null || getPath().length() == 0) {
if (beanName != null && beanName.length() > 0
&& getInterface() != null && getInterface().length() > 0
&& beanName.startsWith(getInterface())) {
setPath(beanName);
}
}
if (!isDelay()) {
export();
}
}
View Code
// publishEvent(Object event, ResolvableType eventType)
protected void publishEvent(Object event, ResolvableType eventType) {
Assert.notNull(event, "Event must not be null");
if (logger.isTraceEnabled()) {
logger.trace("Publishing event in " + getDisplayName() + ": " + event);
}
// Decorate event as an ApplicationEvent if necessary
ApplicationEvent applicationEvent;
if (event instanceof ApplicationEvent) {
applicationEvent = (ApplicationEvent) event;
}
else {
applicationEvent = new PayloadApplicationEvent<Object>(this, event);
if (eventType == null) {
eventType = ((PayloadApplicationEvent) applicationEvent).getResolvableType();
}
}
// Multicast right now if possible - or lazily once the multicaster is initialized
if (this.earlyApplicationEvents != null) {
this.earlyApplicationEvents.add(applicationEvent);
}
else {
// 就这一句，开始调用dubbo-bean
getApplicationEventMulticaster().multicastEvent(applicationEvent, eventType);
}
// Publish event via parent context as well...
if (this.parent != null) {
if (this.parent instanceof AbstractApplicationContext) {
((AbstractApplicationContext) this.parent).publishEvent(event, eventType);
}
else {
this.parent.publishEvent(event);
}
}
}
// publishEvent 后， 由 ServiceBean.onApplicationEvent() 接收请求, 进行接口暴露
@Override
public void onApplicationEvent(ContextRefreshedEvent event) {
if (isDelay() && !isExported() && !isUnexported()) {
if (logger.isInfoEnabled()) {
logger.info("The service ready on spring started. service: " + getInterface());
}
export();
}
}
@Override
public void multicastEvent(final ApplicationEvent event, ResolvableType eventType) {
ResolvableType type = (eventType != null ? eventType : resolveDefaultEventType(event));
for (final ApplicationListener<?> listener : getApplicationListeners(event, type)) {
Executor executor = getTaskExecutor();
if (executor != null) {
executor.execute(new Runnable() {
@Override
public void run() {
invokeListener(listener, event);
}
});
}
else {
invokeListener(listener, event);
}
}
}
// one more...
public synchronized void export() {
if (provider != null) {
if (export == null) {
export = provider.getExport();
}
if (delay == null) {
delay = provider.getDelay();
}
}
if (export != null && !export) {
return;
}
if (delay != null && delay > 0) {
delayExportExecutor.schedule(new Runnable() {
@Override
public void run() {
doExport();
}
}, delay, TimeUnit.MILLISECONDS);
} else {
doExport();
}
}
// one more...
protected synchronized void doExport() {
if (unexported) {
throw new IllegalStateException("Already unexported!");
}
if (exported) {
return;
}
exported = true;
if (interfaceName == null || interfaceName.length() == 0) {
throw new IllegalStateException("<dubbo:service interface=/"/" /> interface not allow null!");
}
checkDefault();
if (provider != null) {
if (application == null) {
application = provider.getApplication();
}
if (module == null) {
module = provider.getModule();
}
if (registries == null) {
registries = provider.getRegistries();
}
if (monitor == null) {
monitor = provider.getMonitor();
}
if (protocols == null) {
protocols = provider.getProtocols();
}
}
if (module != null) {
if (registries == null) {
registries = module.getRegistries();
}
if (monitor == null) {
monitor = module.getMonitor();
}
}
if (application != null) {
if (registries == null) {
registries = application.getRegistries();
}
if (monitor == null) {
monitor = application.getMonitor();
}
}
if (ref instanceof GenericService) {
interfaceClass = GenericService.class;
if (StringUtils.isEmpty(generic)) {
generic = Boolean.TRUE.toString();
}
} else {
try {
interfaceClass = Class.forName(interfaceName, true, Thread.currentThread()
.getContextClassLoader());
} catch (ClassNotFoundException e) {
throw new IllegalStateException(e.getMessage(), e);
}
checkInterfaceAndMethods(interfaceClass, methods);
checkRef();
generic = Boolean.FALSE.toString();
}
if (local != null) {
if ("true".equals(local)) {
local = interfaceName + "Local";
}
Class<?> localClass;
try {
localClass = ClassHelper.forNameWithThreadContextClassLoader(local);
} catch (ClassNotFoundException e) {
throw new IllegalStateException(e.getMessage(), e);
}
if (!interfaceClass.isAssignableFrom(localClass)) {
throw new IllegalStateException("The local implementation class " + localClass.getName() + " not implement interface " + interfaceName);
}
}
if (stub != null) {
if ("true".equals(stub)) {
stub = interfaceName + "Stub";
}
Class<?> stubClass;
try {
stubClass = ClassHelper.forNameWithThreadContextClassLoader(stub);
} catch (ClassNotFoundException e) {
throw new IllegalStateException(e.getMessage(), e);
}
if (!interfaceClass.isAssignableFrom(stubClass)) {
throw new IllegalStateException("The stub implementation class " + stubClass.getName() + " not implement interface " + interfaceName);
}
}
// 检查应用，未加载的配置，属于重新加载
checkApplication();
// 检查注册中心并加载
checkRegistry();
// 检测注册使用的协议
checkProtocol();
// 配置当前service
appendProperties(this);
// 检查mock返回设置
checkStubAndMock(interfaceClass);
if (path == null || path.length() == 0) {
path = interfaceName;
}
// 导出url
doExportUrls();
// 初始化本地提供服务的列表
ProviderModel providerModel = new ProviderModel(getUniqueServiceName(), this, ref);
ApplicationModel.initProviderModel(getUniqueServiceName(), providerModel);
}
// 加载配置，如: <dubbo:protocol name="dubbo" port="20880" id="dubbo" />
protected static void appendProperties(AbstractConfig config) {
if (config == null) {
return;
}
String prefix = "dubbo." + getTagName(config.getClass()) + ".";
Method[] methods = config.getClass().getMethods();
for (Method method : methods) {
try {
String name = method.getName();
if (name.length() > 3 && name.startsWith("set") && Modifier.isPublic(method.getModifiers())
&& method.getParameterTypes().length == 1 && isPrimitive(method.getParameterTypes()[0])) {
String property = StringUtils.camelToSplitName(name.substring(3, 4).toLowerCase() + name.substring(4), ".");
String value = null;
if (config.getId() != null && config.getId().length() > 0) {
String pn = prefix + config.getId() + "." + property;
value = System.getProperty(pn);
if (!StringUtils.isBlank(value)) {
logger.info("Use System Property " + pn + " to config dubbo");
}
}
if (value == null || value.length() == 0) {
String pn = prefix + property;
value = System.getProperty(pn);
if (!StringUtils.isBlank(value)) {
logger.info("Use System Property " + pn + " to config dubbo");
}
}
if (value == null || value.length() == 0) {
Method getter;
try {
getter = config.getClass().getMethod("get" + name.substring(3));
} catch (NoSuchMethodException e) {
try {
getter = config.getClass().getMethod("is" + name.substring(3));
} catch (NoSuchMethodException e2) {
getter = null;
}
}
if (getter != null) {
if (getter.invoke(config) == null) {
if (config.getId() != null && config.getId().length() > 0) {
value = ConfigUtils.getProperty(prefix + config.getId() + "." + property);
}
if (value == null || value.length() == 0) {
value = ConfigUtils.getProperty(prefix + property);
}
if (value == null || value.length() == 0) {
String legacyKey = legacyProperties.get(prefix + property);
if (legacyKey != null && legacyKey.length() > 0) {
value = convertLegacyValue(legacyKey, ConfigUtils.getProperty(legacyKey));
}
}
}
}
}
if (value != null && value.length() > 0) {
method.invoke(config, convertPrimitive(method.getParameterTypes()[0], value));
}
}
} catch (Exception e) {
logger.error(e.getMessage(), e);
}
}
}
// 展出服务url <dubbo:registry address="multicast://224.5.6.7:1234" id="com.alibaba.dubbo.config.RegistryConfig" />
// 展出服务url <dubbo:registry address="multicast://224.5.6.7:1234" id="com.alibaba.dubbo.config.RegistryConfig" />
@SuppressWarnings({"unchecked", "rawtypes"})
private void doExportUrls() {
List<URL> registryURLs = loadRegistries(true);
for (ProtocolConfig protocolConfig : protocols) {
doExportUrlsFor1Protocol(protocolConfig, registryURLs);
}
}
// 注册服务
protected List<URL> loadRegistries(boolean provider) {
checkRegistry();
List<URL> registryList = new ArrayList<URL>();
if (registries != null && !registries.isEmpty()) {
for (RegistryConfig config : registries) {
String address = config.getAddress();
if (address == null || address.length() == 0) {
address = Constants.ANYHOST_VALUE;
}
String sysaddress = System.getProperty("dubbo.registry.address");
if (sysaddress != null && sysaddress.length() > 0) {
address = sysaddress;
}
if (address.length() > 0 && !RegistryConfig.NO_AVAILABLE.equalsIgnoreCase(address)) {
Map<String, String> map = new HashMap<String, String>();
appendParameters(map, application);
appendParameters(map, config);
map.put("path", RegistryService.class.getName());
map.put("dubbo", Version.getProtocolVersion());
map.put(Constants.TIMESTAMP_KEY, String.valueOf(System.currentTimeMillis()));
if (ConfigUtils.getPid() > 0) {
map.put(Constants.PID_KEY, String.valueOf(ConfigUtils.getPid()));
}
if (!map.containsKey("protocol")) {
if (ExtensionLoader.getExtensionLoader(RegistryFactory.class).hasExtension("remote")) {
map.put("protocol", "remote");
} else {
map.put("protocol", "dubbo");
}
}
List<URL> urls = UrlUtils.parseURLs(address, map);
for (URL url : urls) {
url = url.addParameter(Constants.REGISTRY_KEY, url.getProtocol());
url = url.setProtocol(Constants.REGISTRY_PROTOCOL);
if ((provider && url.getParameter(Constants.REGISTER_KEY, true))
|| (!provider && url.getParameter(Constants.SUBSCRIBE_KEY, true))) {
registryList.add(url);
}
}
}
}
}
return registryList;
}
// 广播地址: multicast://224.5.6.7:1234/com.alibaba.dubbo.registry.RegistryService?application=demo-provider&dubbo=2.0.2&pid=14228&qos.port=22222×tamp=1535020152415
// 注册地址: registry://224.5.6.7:1234/com.alibaba.dubbo.registry.RegistryService?application=demo-provider&dubbo=2.0.2&pid=14228&qos.port=22222®istry=multicast×tamp=1535020152415
// doExportUrlsFor1Protocol(protocolConfig, registryURLs);
private void doExportUrlsFor1Protocol(ProtocolConfig protocolConfig, List<URL> registryURLs) {
String name = protocolConfig.getName();
if (name == null || name.length() == 0) {
name = "dubbo";
}
Map<String, String> map = new HashMap<String, String>();
map.put(Constants.SIDE_KEY, Constants.PROVIDER_SIDE);
map.put(Constants.DUBBO_VERSION_KEY, Version.getProtocolVersion());
map.put(Constants.TIMESTAMP_KEY, String.valueOf(System.currentTimeMillis()));
if (ConfigUtils.getPid() > 0) {
map.put(Constants.PID_KEY, String.valueOf(ConfigUtils.getPid()));
}
appendParameters(map, application);
appendParameters(map, module);
appendParameters(map, provider, Constants.DEFAULT_KEY);
appendParameters(map, protocolConfig);
appendParameters(map, this);
if (methods != null && !methods.isEmpty()) {
for (MethodConfig method : methods) {
appendParameters(map, method, method.getName());
String retryKey = method.getName() + ".retry";
if (map.containsKey(retryKey)) {
String retryValue = map.remove(retryKey);
if ("false".equals(retryValue)) {
map.put(method.getName() + ".retries", "0");
}
}
List<ArgumentConfig> arguments = method.getArguments();
if (arguments != null && !arguments.isEmpty()) {
for (ArgumentConfig argument : arguments) {
// convert argument type
if (argument.getType() != null && argument.getType().length() > 0) {
Method[] methods = interfaceClass.getMethods();
// visit all methods
if (methods != null && methods.length > 0) {
for (int i = 0; i < methods.length; i++) {
String methodName = methods[i].getName();
// target the method, and get its signature
if (methodName.equals(method.getName())) {
Class<?>[] argtypes = methods[i].getParameterTypes();
// one callback in the method
if (argument.getIndex() != -1) {
if (argtypes[argument.getIndex()].getName().equals(argument.getType())) {
appendParameters(map, argument, method.getName() + "." + argument.getIndex());
} else {
throw new IllegalArgumentException("argument config error : the index attribute and type attribute not match :index :" + argument.getIndex() + ", type:" + argument.getType());
}
} else {
// multiple callbacks in the method
for (int j = 0; j < argtypes.length; j++) {
Class<?> argclazz = argtypes[j];
if (argclazz.getName().equals(argument.getType())) {
appendParameters(map, argument, method.getName() + "." + j);
if (argument.getIndex() != -1 && argument.getIndex() != j) {
throw new IllegalArgumentException("argument config error : the index attribute and type attribute not match :index :" + argument.getIndex() + ", type:" + argument.getType());
}
}
}
}
}
}
}
} else if (argument.getIndex() != -1) {
appendParameters(map, argument, method.getName() + "." + argument.getIndex());
} else {
throw new IllegalArgumentException("argument config must set index or type attribute.eg: <dubbo:argument index='0' .../> or <dubbo:argument type=xxx .../>");
}
}
}
} // end of methods for
}
if (ProtocolUtils.isGeneric(generic)) {
map.put(Constants.GENERIC_KEY, generic);
map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
} else {
String revision = Version.getVersion(interfaceClass, version);
if (revision != null && revision.length() > 0) {
map.put("revision", revision);
}
String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames();
if (methods.length == 0) {
logger.warn("NO method found in service interface " + interfaceClass.getName());
map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
} else {
map.put(Constants.METHODS_KEY, StringUtils.join(new HashSet<String>(Arrays.asList(methods)), ","));
}
}
if (!ConfigUtils.isEmpty(token)) {
if (ConfigUtils.isDefault(token)) {
map.put(Constants.TOKEN_KEY, UUID.randomUUID().toString());
} else {
map.put(Constants.TOKEN_KEY, token);
}
}
if (Constants.LOCAL_PROTOCOL.equals(protocolConfig.getName())) {
protocolConfig.setRegister(false);
map.put("notify", "false");
}
// export service
String contextPath = protocolConfig.getContextpath();
if ((contextPath == null || contextPath.length() == 0) && provider != null) {
contextPath = provider.getContextpath();
}
String host = this.findConfigedHosts(protocolConfig, registryURLs, map);
Integer port = this.findConfigedPorts(protocolConfig, name, map);
URL url = new URL(name, host, port, (contextPath == null || contextPath.length() == 0 ? "" : contextPath + "/") + path, map);
if (ExtensionLoader.getExtensionLoader(ConfiguratorFactory.class)
.hasExtension(url.getProtocol())) {
url = ExtensionLoader.getExtensionLoader(ConfiguratorFactory.class)
.getExtension(url.getProtocol()).getConfigurator(url).configure(url);
}
String scope = url.getParameter(Constants.SCOPE_KEY);
// don't export when none is configured
if (!Constants.SCOPE_NONE.toString().equalsIgnoreCase(scope)) {
// export to local if the config is not remote (export to remote only when config is remote)
if (!Constants.SCOPE_REMOTE.toString().equalsIgnoreCase(scope)) {
// 本地运行时会注册服务到本地
exportLocal(url);
}
// export to remote if the config is not local (export to local only when config is local)
if (!Constants.SCOPE_LOCAL.toString().equalsIgnoreCase(scope)) {
if (logger.isInfoEnabled()) {
logger.info("Export dubbo service " + interfaceClass.getName() + " to url " + url);
}
if (registryURLs != null && !registryURLs.isEmpty()) {
for (URL registryURL : registryURLs) {
url = url.addParameterIfAbsent(Constants.DYNAMIC_KEY, registryURL.getParameter(Constants.DYNAMIC_KEY));
URL monitorUrl = loadMonitor(registryURL);
if (monitorUrl != null) {
url = url.addParameterAndEncoded(Constants.MONITOR_KEY, monitorUrl.toFullString());
}
if (logger.isInfoEnabled()) {
logger.info("Register dubbo service " + interfaceClass.getName() + " url " + url + " to registry " + registryURL);
}
// For providers, this is used to enable custom proxy to generate invoker
String proxy = url.getParameter(Constants.PROXY_KEY);
if (StringUtils.isNotEmpty(proxy)) {
registryURL = registryURL.addParameter(Constants.PROXY_KEY, proxy);
}
Invoker<?> invoker = proxyFactory.getInvoker(ref, (Class) interfaceClass, registryURL.addParameterAndEncoded(Constants.EXPORT_KEY, url.toFullString()));
DelegateProviderMetaDataInvoker wrapperInvoker = new DelegateProviderMetaDataInvoker(invoker, this);
// subscribeUrl: provider://192.168.11.6:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&category=configurators&check=false&dubbo=2.0.2&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=14228&side=provider×tamp=1535020596190
// registerUrl: dubbo://192.168.11.6:20880/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&dubbo=2.0.2&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=14228&side=provider×tamp=1535020596190
Exporter<?> exporter = protocol.export(wrapperInvoker);
exporters.add(exporter);
}
} else {
Invoker<?> invoker = proxyFactory.getInvoker(ref, (Class) interfaceClass, url);
DelegateProviderMetaDataInvoker wrapperInvoker = new DelegateProviderMetaDataInvoker(invoker, this);
Exporter<?> exporter = protocol.export(wrapperInvoker);
exporters.add(exporter);
}
}
}
this.urls.add(url);
}
// 导出服务到本地
@SuppressWarnings({"unchecked", "rawtypes"})
private void exportLocal(URL url) {
if (!Constants.LOCAL_PROTOCOL.equalsIgnoreCase(url.getProtocol())) {
URL local = URL.valueOf(url.toFullString())
.setProtocol(Constants.LOCAL_PROTOCOL)
.setHost(LOCALHOST)
.setPort(0);
ServiceClassHolder.getInstance().pushServiceClass(getServiceClass(ref));
// 执行真正的导出服务暴露
// 链接如下: injvm://127.0.0.1/com.alibaba.dubbo.demo.DemoService?anyhost=true&application=demo-provider&bind.ip=192.168.11.6&bind.port=20880&dubbo=2.0.2&generic=false&interface=com.alibaba.dubbo.demo.DemoService&methods=sayHello&pid=14228&qos.port=22222&side=provider×tamp=1535020596190
Exporter<?> exporter = protocol.export(
proxyFactory.getInvoker(ref, (Class) interfaceClass, local));
exporters.add(exporter);
logger.info("Export dubbo service " + interfaceClass.getName() + " to local registry");
}
}
// 以上是通过本方广播的方式进行提供dubbo服务，使其运行在本地jvm中的运行调用链。
// 下面来看看dubbo以远程调用形式进行提供服务的情况
// DubboProtocol.export(), 以dubbo协议远程暴露dubbo
@Override
public <T> Exporter<T> export(Invoker<T> invoker) throws RpcException {
URL url = invoker.getUrl();
// export service.
String key = serviceKey(url);
DubboExporter<T> exporter = new DubboExporter<T>(invoker, key, exporterMap);
exporterMap.put(key, exporter);
//export an stub service for dispatching event
Boolean isStubSupportEvent = url.getParameter(Constants.STUB_EVENT_KEY, Constants.DEFAULT_STUB_EVENT);
Boolean isCallbackservice = url.getParameter(Constants.IS_CALLBACK_SERVICE, false);
if (isStubSupportEvent && !isCallbackservice) {
String stubServiceMethods = url.getParameter(Constants.STUB_EVENT_METHODS_KEY);
if (stubServiceMethods == null || stubServiceMethods.length() == 0) {
if (logger.isWarnEnabled()) {
logger.warn(new IllegalStateException("consumer [" + url.getParameter(Constants.INTERFACE_KEY) +
"], has set stubproxy support event ,but no stub methods founded."));
}
} else {
stubServiceMethodsMap.put(url.getServiceKey(), stubServiceMethods);
}
}
openServer(url);
optimizeSerialization(url);
return exporter;
}
private void openServer(URL url) {
// find server.
String key = url.getAddress();
//client can export a service which's only for server to invoke
boolean isServer = url.getParameter(Constants.IS_SERVER_KEY, true);
if (isServer) {
ExchangeServer server = serverMap.get(key);
if (server == null) {
serverMap.put(key, createServer(url));
} else {
// server supports reset, use together with override
server.reset(url);
}
}
}
private ExchangeServer createServer(URL url) {
// send readonly event when server closes, it's enabled by default
url = url.addParameterIfAbsent(Constants.CHANNEL_READONLYEVENT_SENT_KEY, Boolean.TRUE.toString());
// enable heartbeat by default
url = url.addParameterIfAbsent(Constants.HEARTBEAT_KEY, String.valueOf(Constants.DEFAULT_HEARTBEAT));
String str = url.getParameter(Constants.SERVER_KEY, Constants.DEFAULT_REMOTING_SERVER);
if (str != null && str.length() > 0 && !ExtensionLoader.getExtensionLoader(Transporter.class).hasExtension(str))
throw new RpcException("Unsupported server type: " + str + ", url: " + url);
url = url.addParameter(Constants.CODEC_KEY, DubboCodec.NAME);
ExchangeServer server;
try {
server = Exchangers.bind(url, requestHandler);
} catch (RemotingException e) {
throw new RpcException("Fail to start server(url: " + url + ") " + e.getMessage(), e);
}
str = url.getParameter(Constants.CLIENT_KEY);
if (str != null && str.length() > 0) {
Set<String> supportedTypes = ExtensionLoader.getExtensionLoader(Transporter.class).getSupportedExtensions();
if (!supportedTypes.contains(str)) {
throw new RpcException("Unsupported client type: " + str);
}
}
return server;
}
// 远程服务框架中dubbo提供的有几种, netty/netty4/Grizzly, 我们就看一下使用netty的方式说明下
public NettyServer(URL url, ChannelHandler handler) throws RemotingException {
super(url, ChannelHandlers.wrap(handler, ExecutorUtil.setThreadName(url, SERVER_THREAD_POOL_NAME)));
}
@Override
protected void doOpen() throws Throwable {
NettyHelper.setNettyLoggerFactory();
ExecutorService boss = Executors.newCachedThreadPool(new NamedThreadFactory("NettyServerBoss", true));
ExecutorService worker = Executors.newCachedThreadPool(new NamedThreadFactory("NettyServerWorker", true));
ChannelFactory channelFactory = new NioServerSocketChannelFactory(boss, worker, getUrl().getPositiveParameter(Constants.IO_THREADS_KEY, Constants.DEFAULT_IO_THREADS));
bootstrap = new ServerBootstrap(channelFactory);
final NettyHandler nettyHandler = new NettyHandler(getUrl(), this);
channels = nettyHandler.getChannels();
// https://issues.jboss.org/browse/NETTY-365
// https://issues.jboss.org/browse/NETTY-379
// final Timer timer = new HashedWheelTimer(new NamedThreadFactory("NettyIdleTimer", true));
bootstrap.setOption("child.tcpNoDelay", true);
bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
@Override
public ChannelPipeline getPipeline() {
NettyCodecAdapter adapter = new NettyCodecAdapter(getCodec(), getUrl(), NettyServer.this);
ChannelPipeline pipeline = Channels.pipeline();
/*int idleTimeout = getIdleTimeout();
if (idleTimeout > 10000) {
pipeline.addLast("timer", new IdleStateHandler(timer, idleTimeout / 1000, 0, 0));
}*/
pipeline.addLast("decoder", adapter.getDecoder());
pipeline.addLast("encoder", adapter.getEncoder());
pipeline.addLast("handler", nettyHandler);
return pipeline;
}
});
// bind
channel = bootstrap.bind(getBindAddress());
}
// server 创建后，对上层是不可见的，上层只知道 Transporter/ExchangeServer
@Override
public ExchangeServer bind(URL url, ExchangeHandler handler) throws RemotingException {
return new HeaderExchangeServer(Transporters.bind(url, new DecodeHandler(new HeaderExchangeHandler(handler))));
}
// HeaderExchangeServer设置好server后，启动一个心跳定时器与注册中心保持关联
public HeaderExchangeServer(Server server) {
if (server == null) {
throw new IllegalArgumentException("server == null");
}
this.server = server;
this.heartbeat = server.getUrl().getParameter(Constants.HEARTBEAT_KEY, 0);
this.heartbeatTimeout = server.getUrl().getParameter(Constants.HEARTBEAT_TIMEOUT_KEY, heartbeat * 3);
if (heartbeatTimeout < heartbeat * 2) {
throw new IllegalStateException("heartbeatTimeout < heartbeatInterval * 2");
}
startHeartbeatTimer();
}
到此，完整的server的启动就完成了，就等待客户端的连接了。
正文到此结束
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666
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文章和留言都翻到11页了 没有OOM
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朋友，翻页到11页，及以后，会出现OOM，无法访问
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版本号是多少，你可以下载哪个代码仓库，jdk选1.8 直接跑就行
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