Spring远程支持简化了启用远程服务的开发。 当前，Spring支持以下远程技术：远程方法调用（RMI），HTTP调用程序，Hessian，Burlap，JAX-RPC，JAX-WS和JMS。

远程方法调用（RMI） ：Spring通过RmiProxyFactoryBean和RmiServiceExporter支持RMI。 RmiServiceExporter将任何Spring管理的bean导出为RMI服务并进行注册。 RmiProxyFactoryBean是一种工厂bean，可为RMI服务创建代理。 该代理对象代表客户端与远程RMI服务进行通信。

Spring的HTTP调用程序： Spring HTTP调用程序使用标准的Java序列化机制通过HTTP公开服务。 Spring通过HttpInvokerProxyFactoryBean和HttpInvokerServiceExporter支持HTTP调用程序基础结构。 HttpInvokerServiceExporter，它将指定的服务bean导出为HTTP调用程序服务终结点，可通过HTTP调用程序代理访问。 HttpInvokerProxyFactoryBean是用于HTTP调用程序代理的工厂bean。

Hessian： Hessian提供了一个基于HTTP的二进制远程协议。 Spring通过HessianProxyFactoryBean和HessianServiceExporter支持Hessian。

粗麻布：粗麻布是Caucho的基于XML的粗麻布替代品。 Spring提供了支持类，例如BurlapProxyFactoryBean和BurlapServiceExporter。

JAX-RPC： Spring通过JAX-RPC（J2EE 1.4的Web服务API）为Web服务提供远程支持。

JAX-WS： Spring通过JAX-WS（Java EE 5和Java 6中引入的JAX-RPC的继承者）为Web服务提供远程支持。

JMS： JmsInvokerServiceExporter和JmsInvokerProxyFactoryBean类提供了Spring中的JMS远程支持。

让我们看一下Spring RMI支持以开发Spring RMI Service＆Client。

二手技术：

JDK 1.6.0_31
春天3.1.1
Maven的3.0.2

步骤1：建立已完成的专案

创建一个Maven项目，如下所示。 （可以使用Maven或IDE插件创建）。

步骤2：图书馆

Spring依赖项已添加到Maven的pom.xml中。

<!-- Spring 3.1.x dependencies -->
<properties><spring.version>3.1.1.RELEASE</spring.version>
</properties><dependencies><dependency><groupId>org.springframework</groupId><artifactId>spring-core</artifactId><version>${spring.version}</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>${spring.version}</version></dependency>
<dependencies>

步骤3：建立使用者类别

创建一个新的用户类。

package com.otv.user;import java.io.Serializable;/*** User Bean** @author  onlinetechvision.com* @since   24 Feb 2012* @version 1.0.0**/
public class User implements Serializable {private long id;private String name;private String surname;/*** Get User Id** @return long id*/public long getId() {return id;}/*** Set User Id** @param long id*/public void setId(long id) {this.id = id;}/*** Get User Name** @return long id*/public String getName() {return name;}/*** Set User Name** @param String name*/public void setName(String name) {this.name = name;}/*** Get User Surname** @return long id*/public String getSurname() {return surname;}/*** Set User Surname** @param String surname*/public void setSurname(String surname) {this.surname = surname;}@Overridepublic String toString() {StringBuilder strBuilder = new StringBuilder();strBuilder.append("Id : ").append(getId());strBuilder.append(", Name : ").append(getName());strBuilder.append(", Surname : ").append(getSurname());return strBuilder.toString();}
}

步骤4：建立ICacheService介面

创建了代表远程缓存服务接口的ICacheService接口。

package com.otv.cache.service;import java.util.concurrent.ConcurrentHashMap;import com.otv.user.User;/*** Cache Service Interface** @author  onlinetechvision.com* @since   27 Feb 2012* @version 1.0.0**/
public interface ICacheService {/*** Get User Map** @return ConcurrentHashMap User Map*/public ConcurrentHashMap<long, user> getUserMap();}

步骤5：创建CacheService类

CacheService类是通过实现ISchedulerService接口创建的。 它提供对远程缓存的访问…

package com.otv.cache.service;import java.util.concurrent.ConcurrentHashMap;import com.otv.user.User;/*** Cache Service Implementation** @author  onlinetechvision.com* @since   6:04:49 PM* @version 1.0.0**/
public class CacheService implements ICacheService {//User Map is injected...ConcurrentHashMap<long, user> userMap;/*** Get User Map** @return ConcurrentHashMap User Map*/public ConcurrentHashMap<long, user> getUserMap() {return userMap;}/*** Set User Map** @param ConcurrentHashMap User Map*/public void setUserMap(ConcurrentHashMap<long, user> userMap) {this.userMap = userMap;}}

步骤6：建立IRMIUserService接口

创建了代表RMI服务接口的IRMIUserService接口。 此外，它为RMI客户端提供了远程方法。

package com.otv.rmi.server;import java.util.List;import com.otv.user.User;/*** RMI User Service Interface** @author  onlinetechvision.com* @since   24 Feb 2012* @version 1.0.0**/
public interface IRMIUserService {/*** Add User** @param  User user* @return boolean response of the method*/public boolean addUser(User user);/*** Delete User** @param  User user* @return boolean response of the method*/public boolean deleteUser(User user);/*** Get User List** @return List user list*/public List<User> getUserList();}

步骤7：创建RMIUserService类

RMIUserService类（又名RMI对象）是通过实现IRMIUserService接口创建的。

package com.otv.rmi.server;import java.util.ArrayList;
import java.util.List;
import org.apache.log4j.Logger;import com.otv.cache.service.ICacheService;
import com.otv.user.User;/*** RMI User Service Implementation** @author  onlinetechvision.com* @since   24 Feb 2012* @version 1.0.0**/
public class RMIUserService implements IRMIUserService {private static Logger logger = Logger.getLogger(RMIUserService.class);//Remote Cache Service is injected...ICacheService cacheService;/*** Add User** @param  User user* @return boolean response of the method*/public boolean addUser(User user) {getCacheService().getUserMap().put(user.getId(), user);logger.debug("User has been added to cache. User : "+getCacheService().getUserMap().get(user.getId()));return true;}/*** Delete User** @param  User user* @return boolean response of the method*/public boolean deleteUser(User user) {getCacheService().getUserMap().put(user.getId(), user);logger.debug("User has been deleted from cache. User : "+user);return true;}/*** Get User List** @return List user list*/public List<User> getUserList() {List<User> list = new ArrayList<User>();list.addAll(getCacheService().getUserMap().values());logger.debug("User List : "+list);return list;}/*** Get RMI User Service** @return IRMIUserService RMI User Service*/public ICacheService getCacheService() {return cacheService;}/*** Set RMI User Service** @param IRMIUserService RMI User Service*/public void setCacheService(ICacheService cacheService) {this.cacheService = cacheService;}
}

步骤8：创建RMIServerStarter类别

RMI服务器启动程序类已创建。 它启动RMI服务器。

package com.otv.rmi.server.starter;import org.springframework.context.support.ClassPathXmlApplicationContext;/*** RMI Server Starter** @author  onlinetechvision.com* @since   27 Feb 2012* @version 1.0.0**/
public class RMIServerStarter {public static void main(String[] args) {//RMI Server Application Context is started...new ClassPathXmlApplicationContext("rmiServerAppContext.xml");}
}

步骤9：创建rmiServerAppContext.xml

RMI服务器应用程序上下文的内容如下所示。

<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.0.xsd"><!-- Beans Declaration --><bean id="UserMap" class="java.util.concurrent.ConcurrentHashMap" /><bean id="CacheService" class="com.otv.cache.service.CacheService"><property name="userMap" ref="UserMap"/></bean>   <bean id="RMIUserService" class="com.otv.rmi.server.RMIUserService" ><property name="cacheService" ref="CacheService"/></bean><!-- RMI Server Declaration --><bean class="org.springframework.remoting.rmi.RmiServiceExporter"><!-- serviceName represents RMI Service Name --><property name="serviceName" value="RMIUserService"/><!-- service represents RMI Object(RMI Service Impl) --><property name="service" ref="RMIUserService"/><!-- serviceInterface represents RMI Service Interface exposed --><property name="serviceInterface" value="com.otv.rmi.server.IRMIUserService"/><!-- defaults to 1099 --><property name="registryPort" value="1099"/></bean></beans>

步骤10：创建RMIServiceClient类

RMIServiceClient类已创建。 它调用RMI用户服务并执行用户操作。

package com.otv.rmi.client;import org.apache.log4j.Logger;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;import com.otv.rmi.server.IRMIUserService;
import com.otv.rmi.server.RMIUserService;
import com.otv.user.User;/*** RMI Service Client** @author  onlinetechvision.com* @since   24 Feb 2012* @version 1.0.0**/
public class RMIServiceClient {private static Logger logger = Logger.getLogger(RMIUserService.class);/*** Main method of the RMI Service Client**/public static void main(String[] args) {logger.debug("RMI Service Client is starting...");//RMI Client Application Context is started...ApplicationContext context = new ClassPathXmlApplicationContext("rmiClientAppContext.xml");//Remote User Service is called via RMI Client Application Context...IRMIUserService rmiClient = (IRMIUserService) context.getBean("RMIUserService");//New User is created...User user = new User();user.setId(1);user.setName("Bruce");user.setSurname("Willis");//The user is added to the remote cache...rmiClient.addUser(user);//The users are gotten via remote cache...rmiClient.getUserList();//The user is deleted from remote cache...rmiClient.deleteUser(user);logger.debug("RMI Service Client is stopped...");}
}

步骤11：创建rmiClientAppContext.xml

RMI客户端应用程序上下文的内容如下所示。

<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.0.xsd"><!-- RMI Client Declaration --><bean id="RMIUserService" class="org.springframework.remoting.rmi.RmiProxyFactoryBean"><!-- serviceUrl represents RMI Service Url called--><property name="serviceUrl" value="rmi://x.x.x.x:1099/RMIUserService"/><!-- serviceInterface represents RMI Service Interface called --><property name="serviceInterface" value="com.otv.rmi.server.IRMIUserService"/><!-- refreshStubOnConnectFailure enforces automatic re-lookup of the stub if acall fails with a connect exception --><property name="refreshStubOnConnectFailure" value="true"/></bean></beans>

步骤12：运行项目

如果运行RMI Server时启动了RMI Service Client，则将在RMI Server输出日志下方显示。 同样，可以通过IDE打开两个单独的控制台来运行RMI Server和Client。 ：

....
04.03.2012 14:23:15 DEBUG (RmiBasedExporter.java:59) - RMI service [com.otv.rmi.server.RMIUserService@16dadf9] is an RMI invoker
04.03.2012 14:23:15 DEBUG (JdkDynamicAopProxy.java:113) - Creating JDK dynamic proxy: target source is SingletonTargetSource for target object [com.otv.rmi.server.RMIUserService@16dadf9]
04.03.2012 14:23:15  INFO (RmiServiceExporter.java:276) - Binding service 'RMIUserService' to RMI registry: RegistryImpl[UnicastServerRef [liveRef: [endpoint:[192.168.1.7:1099](local),objID:[0:0:0, 0]]]]
04.03.2012 14:23:15 DEBUG (AbstractAutowireCapableBeanFactory.java:458) - Finished creating instance of bean 'org.springframework.remoting.rmi.RmiServiceExporter#0'
04.03.2012 14:23:15 DEBUG (AbstractApplicationContext.java:845) - Unable to locate LifecycleProcessor with name 'lifecycleProcessor': using default [org.springframework.context.support.DefaultLifecycleProcessor@3c0007]
04.03.2012 14:23:15 DEBUG (AbstractBeanFactory.java:245) - Returning cached instance of singleton bean 'lifecycleProcessor'04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:73) - Incoming RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.addUser
04.03.2012 14:25:43 DEBUG (RMIUserService.java:33) - User has been added to cache. User : Id : 1, Name : Bruce, Surname : Willis
04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:79) - Finished processing of RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.addUser04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:73) - Incoming RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.getUserList
04.03.2012 14:25:43 DEBUG (RMIUserService.java:57) - User List : [Id : 1, Name : Bruce, Surname : Willis]
04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:79) - Finished processing of RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.getUserList04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:73) - Incoming RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.deleteUser
04.03.2012 14:25:43 DEBUG (RMIUserService.java:45) - User has been deleted from cache. User : Id : 1, Name : Bruce, Surname : Willis
04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:79) - Finished processing of RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.deleteUser04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:73) - Incoming RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.getUserList
04.03.2012 14:25:43 DEBUG (RMIUserService.java:57) - User List : []
04.03.2012 14:25:43 DEBUG (RemoteInvocationTraceInterceptor.java:79) - Finished processing of RmiServiceExporter remote call: com.otv.rmi.server.IRMIUserService.getUserList

步骤13：下载

OTV_SpringRMI

参考： Online Technology Vision博客中的JCG合作伙伴 Eren Avsarogullari的Spring Remoting支持和RMI服务开发 。