最近做系统重构，计划将多个系统的公共部分抽取出来作为一项公共服务，为以后项目维护和横向扩展奠定基础。

常用的服务发布方式有RMI / HTTPInvoker / Hessian / Burlap，关于这几类java远程服务的性能比较和优缺点大家可参考：http://www.cnblogs.com/jifeng/archive/2011/07/20/2111183.html ，本文着重讲解怎样使用自定的注解标签，结合SPRING将服务方便的发布出去。

一、 Maven配置

                
     
      junit
                 
     
      junit
                 
     
      4.7
                 
     
      test
             
            
                
     
      org.springframework
                 
     
      spring-core
                 
     
      3.1.1.RELEASE
             
            
                
     
      org.springframework
                 
     
      spring-context
                 
     
      3.1.1.RELEASE
             
            
                
     
      org.springframework
                 
     
      spring-beans
                 
     
      3.1.1.RELEASE
             
            
                
     
      org.springframework
                 
     
      spring-webmvc
                 
     
      3.1.1.RELEASE
             
            
                
     
      com.caucho
                 
     
      hessian
                 
     
      4.0.38
             
            
                
     
      org.springframework
                 
     
      spring-test
                 
     
      3.1.1.RELEASE
             
            
                
     
      org.eclipse.jetty
                 
     
      jetty-webapp
                 
     
      8.1.3.v20120416
             
    

二、自定义Annotation注解标签（RemoteService）

package org.springframework.remoting;import java.lang.annotation.Documented;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;import org.springframework.stereotype.Component;@Target({ ElementType.TYPE })@Retention(RetentionPolicy.RUNTIME)@Documented@Componentpublic @interface RemoteService {    ServiceType serviceType() default ServiceType.HTTP;    Class
     serviceInterface();}

RemoteService辅助标签RmiServiceProperty，在发布RMI服务时，用来指定RMI服务发布的端口。

package org.springframework.remoting;import org.springframework.stereotype.Component;import java.lang.annotation.*;import java.rmi.registry.Registry;/** * Created by Administrator on 2014/12/8. */@Target({ ElementType.TYPE })@Retention(RetentionPolicy.RUNTIME)@Documented@Componentpublic @interface RmiServiceProperty {    int registryPort() default Registry.REGISTRY_PORT;}

ServiceType，指定发布服务的类型

package org.springframework.remoting;public enum ServiceType {    HTTP, BURLAP, HESSIAN, RMI}

三、 定义Annotation标签解释器

public class ServiceAnnotationBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter implements PriorityOrdered {    private int order = Ordered.LOWEST_PRECEDENCE - 1;    @Override    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {        RemoteService service = AnnotationUtils.findAnnotation(bean.getClass(), RemoteService.class);        Object resultBean = bean;        if (null != service) {            if (ServiceType.HTTP == service.serviceType()) {                if(!beanName.startsWith("/")){                    throw new FatalBeanException("Exception initializing  HttpInvokerService for "+beanName+",beanName should bean start with \"/\".");                }                HttpInvokerServiceExporter httpInvokerServiceExporter = new HttpInvokerServiceExporter();                httpInvokerServiceExporter.setServiceInterface(service.serviceInterface());                httpInvokerServiceExporter.setService(bean);                httpInvokerServiceExporter.afterPropertiesSet();                resultBean = httpInvokerServiceExporter;            } else if (ServiceType.HESSIAN == service.serviceType()) {                if(!beanName.startsWith("/")){                    throw new FatalBeanException("Exception initializing  HessianService for "+beanName+",beanName should bean start with \"/\".");                }                HessianServiceExporter hessianServiceExporter = new HessianServiceExporter();                hessianServiceExporter.setServiceInterface(service.serviceInterface());                hessianServiceExporter.setService(bean);                hessianServiceExporter.afterPropertiesSet();                resultBean = hessianServiceExporter;            } else if (ServiceType.BURLAP == service.serviceType()) {                if(!beanName.startsWith("/")){                    throw new FatalBeanException("Exception initializing BurlapService for "+beanName+",beanName should bean start with \"/\".");                }                BurlapServiceExporter burlapServiceExporter = new BurlapServiceExporter();                burlapServiceExporter.setServiceInterface(service.serviceInterface());                burlapServiceExporter.setService(bean);                burlapServiceExporter.afterPropertiesSet();                resultBean = burlapServiceExporter;            } else if (ServiceType.RMI == service.serviceType()) {                RmiServiceExporter rmiServiceExporter = new RmiServiceExporter();                rmiServiceExporter.setServiceInterface(service.serviceInterface());                rmiServiceExporter.setService(bean);                RmiServiceProperty rmiServiceProperty = bean.getClass().getAnnotation(RmiServiceProperty.class);                if(rmiServiceProperty!=null){                    rmiServiceExporter.setRegistryPort(rmiServiceProperty.registryPort());                }                String serviceName = beanName;                if(serviceName.startsWith("/")){                    serviceName = serviceName.substring(1);                }                rmiServiceExporter.setServiceName(serviceName);                try {                    rmiServiceExporter.afterPropertiesSet();                } catch (RemoteException remoteException) {                    throw new FatalBeanException("Exception initializing RmiServiceExporter", remoteException);                }                resultBean = rmiServiceExporter;            }        }        return resultBean;    }    /******      参考附件     ******/}

四、重写Spring框架AnnotationConfigUtils

请注意package和Class Name必须一致

package org.springframework.context.annotation;public class AnnotationConfigUtils {    /******      参考附件     ******/	/**	 * Register all relevant annotation post processors in the given registry.	 * @param registry the registry to operate on	 * @param source the configuration source element (already extracted)	 * that this registration was triggered from. May be null.	 * @return a Set of BeanDefinitionHolders, containing all bean definitions	 * that have actually been registered by this call	 */	public static Set
    
      registerAnnotationConfigProcessors(			BeanDefinitionRegistry registry, Object source) {		Set
     
       beanDefs = new LinkedHashSet
      
       (4);        if (!registry.containsBeanDefinition(SERVICE_ANNOTATION_PROCESSOR_BEAN_NAME)) {            RootBeanDefinition def = new RootBeanDefinition(ServiceAnnotationBeanPostProcessor.class);            def.setSource(source);            def.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);            beanDefs.add(registerPostProcessor(registry, def, SERVICE_ANNOTATION_PROCESSOR_BEAN_NAME));        }        /*******    参考附件    *******/		return beanDefs;	}	/*******    参考附件    *******/}
      
     
    

五、发布服务

        服务接口

public interface HttpDateService {    public Date getDate();}

        发布服务

@RemoteService(serviceInterface = HttpDateService.class, serviceType = ServiceType.HTTP)public class HttpDateServiceImpl implements HttpDateService {    @Override    public Date getDate() {        return new Date();    }}

        SPRING基础配置

      其他类型的服务发布请参考附件。

六、测试服务

本次测试使用Junit4结合Spring容器测试服务。

Client Spring配置

服务测试基础类，使用注解（RunWith/ ContextConfiguration）初始化Spring容器，测试具体的逻辑前，先将项目发布到Jetty容器中。

@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration(locations ={"classpath:DateServiceTest-context.xml"})public class ServerRunner {    private static Server server;    @BeforeClass    public static void startWebapp() throws Exception {        server = new Server();        Connector connector = new SelectChannelConnector();        connector.setPort(8080);        server.addConnector(connector);        WebAppContext webAppContext = new WebAppContext();        webAppContext.setContextPath("/remoting");        webAppContext.setWar("src/main/webapp");        server.setHandler(webAppContext);        server.start();        System.out.println("syetem start sucess.");    }    @AfterClass    public static void stopWebapp() throws Exception {        server.stop();    }}

服务接口测试

public class HttpDateServiceTest extends ServerRunner {    @Resource(name = "httpDateService")    private HttpDateService httpDateService;    @Test    public void getGetDate() {        System.out.println(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(httpDateService.getDate()));    }}

测试结果：

syetem start sucess.2014-12-09 10:43:34

源码地址：