1)看看dubbo中的dubbo-registry-simple.xml文件,这个文件是dubbo在spring中的bean基于dubbo自己定义的schema文件来配置的。
有了上节介绍的知识,现在来看看这个文件就很好理解了。
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dubbo="http://code.alibabatech.com/schema/dubbo" //dubbo定义 xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://code.alibabatech.com/schema/dubbo http://code.alibabatech.com/schema/dubbo/dubbo.xsd">//dubbo定义的XSD文件 <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="systemPropertiesModeName" value="SYSTEM_PROPERTIES_MODE_OVERRIDE" /> <property name="location" value="classpath:dubbo.properties" /> </bean> <dubbo:application name="${dubbo.application.name}" owner="${dubbo.application.owner}" /> <dubbo:protocol name="dubbo" port="${dubbo.protocol.port}" heartbeat="180000" /> <dubbo:service id="registryServiceConfig" interface="com.alibaba.dubbo.registry.RegistryService" ref="registryService" registry="N/A" ondisconnect="disconnect" callbacks="1000"> <dubbo:method name="subscribe"><dubbo:argument index="1" callback="true" /></dubbo:method> <dubbo:method name="unsubscribe"><dubbo:argument index="1" callback="false" /></dubbo:method> </dubbo:service> <bean id="registryService" class="com.alibaba.dubbo.registry.simple.SimpleRegistryService" /> </beans>
有以上的配置文件,就应该有相对应的一套schema体现。
2)接下来我们看看NamespaceHandlerSupport:
在dubbo中DubboNamespaceHandler继承了NamespaceHandlerSupport:
根据XSD文件中的节点名称找到自己制定的BeanDefinitionParser,然后由BeanDefinitionParser完成具体的解析工作。
public class DubboNamespaceHandler extends NamespaceHandlerSupport { static { Version.checkDuplicate(DubboNamespaceHandler.class); } public void init() { registerBeanDefinitionParser("application", new DubboBeanDefinitionParser(ApplicationConfig.class, true)); registerBeanDefinitionParser("module", new DubboBeanDefinitionParser(ModuleConfig.class, true)); registerBeanDefinitionParser("registry", new DubboBeanDefinitionParser(RegistryConfig.class, true)); registerBeanDefinitionParser("monitor", new DubboBeanDefinitionParser(MonitorConfig.class, true)); registerBeanDefinitionParser("provider", new DubboBeanDefinitionParser(ProviderConfig.class, true)); registerBeanDefinitionParser("consumer", new DubboBeanDefinitionParser(ConsumerConfig.class, true)); registerBeanDefinitionParser("protocol", new DubboBeanDefinitionParser(ProtocolConfig.class, true)); registerBeanDefinitionParser("service", new DubboBeanDefinitionParser(ServiceBean.class, true)); registerBeanDefinitionParser("reference", new DubboBeanDefinitionParser(ReferenceBean.class, false)); registerBeanDefinitionParser("annotation", new DubboBeanDefinitionParser(AnnotationBean.class, true)); } }
例如:registerBeanDefinitionParser("application", new DubboBeanDefinitionParser(ApplicationConfig.class, true));
会根据application名称,找到XSD中配置的BEAN信息,由DubboBeanDefinitionParser来完成解析工作。
XSD中application节点:
<xsd:element name="application" type="applicationType"> <xsd:annotation> <xsd:documentation><![CDATA[ The application config ]]></xsd:documentation> </xsd:annotation> </xsd:element> <xsd:complexType name="applicationType"> <xsd:attribute name="id" type="xsd:ID"> <xsd:annotation> <xsd:documentation><![CDATA[ The unique identifier for a bean. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="name" type="xsd:string" use="required"> <xsd:annotation> <xsd:documentation><![CDATA[ The application name. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="version" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The application version. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="owner" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The application owner name (email prefix). ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="organization" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The organization name. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="architecture" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The architecture. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="environment" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The application environment, eg: dev/test/run ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="compiler" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The java code compiler. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="logger" type="xsd:string"> <xsd:annotation> <xsd:documentation><![CDATA[ The application logger. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="registry" type="xsd:string" use="optional"> <xsd:annotation> <xsd:documentation><![CDATA[ The application registry. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="monitor" type="xsd:string" use="optional"> <xsd:annotation> <xsd:documentation><![CDATA[ The application monitor. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> <xsd:attribute name="default" type="xsd:string" use="optional"> <xsd:annotation> <xsd:documentation><![CDATA[ Is default. ]]></xsd:documentation> </xsd:annotation> </xsd:attribute> </xsd:complexType>
对应的bean信息:
ApplicationConfig类:
// 应用名称 private String name; // 模块版本 private String version; // 应用负责人 private String owner; // 组织名(BU或部门) private String organization; // 分层 private String architecture; // 环境,如:dev/test/run private String environment; // Java代码编译器 private String compiler; // 日志输出方式 private String logger; // 注册中心 private List<RegistryConfig> registries; // 服务监控 private MonitorConfig monitor; // 是否为缺省 private Boolean isDefault;
DubboBeanDefinitionParser自然就会实现BeanDefinitionParser接口了。
把XSD文件中配置的值写到bean(ApplicationConfig)中
dubbo对于每一个节点的解析都是同一个解析器, 这点的做法有点待商榷。
3)下面就是应该是spring.handlers和spring.schemas了
指定http://code.alibabatech.com/schema/dubbo/dubbo.xsd对于的xsd文件
在META-INF/spring.schemas定义
http\://code.alibabatech.com/schema/dubbo/dubbo.xsd=META-INF/dubbo.xsd
在META-INF/spring.handlers定义
http\://code.alibabatech.com/schema/dubbo=com.alibaba.dubbo.config.spring.schema.DubboNamespaceHandler
经过这2节的介绍,可以比较清楚的了解了,dubbo和spring的结合了!