基于Spring的RPC通讯模型.

    /**
     * 服务端：
     * <p>
     * 1、默认情况下，RmiServiceExporter 会尝试绑定到本地机器1099端口上的RMI注册表。
     * 2、如果在这个端口没有发现RMI注册表，RmiServiceExporter 将会启动一个注册表。
     * 3、可重写注册表的路径和端口，这个是个大坑，当你设置了registryHost属性的时候，源码中就不创建Registry，而是直接去获取，可是我们自己也没有创建，所以就会报连接不上。
     *
     * @param userService
     * @return
     */
    @Bean(name = "rmiServiceExporter")
    public RmiExporter rmiServiceExporter(UserService userService, Environment environment) {
        String registryHost = environment.getProperty("registryHost");
        int registryPort = environment.getProperty("registryPort", Integer.class);
        RmiExporter rmiExporter = new RmiExporter();
        rmiExporter.setService(userService); //要把该bean(即rmiServiceImpl)发布为一个RMI服务
        rmiExporter.setServiceName("RmiService"); //命名RMI 服务
        rmiExporter.setServiceInterface(UserService.class); //指定服务所实现的接口
        rmiExporter.setRegistryHost(registryHost);
        rmiExporter.setRegistryPort(registryPort);
        return rmiExporter;
    }

    @Bean(name = "rmiUserServiceClient")
    public RmiProxyFactoryBean RmiUserServiceClient(){
        RmiProxyFactoryBean rmiProxyFactoryBean = new RmiProxyFactoryBean();
        rmiProxyFactoryBean.setServiceUrl("rmi://127.0.0.1:9999/RmiService");
        rmiProxyFactoryBean.setServiceInterface(UserService.class);
        rmiProxyFactoryBean.setLookupStubOnStartup(false);//不在容器启动后创建与Server端的连接
        rmiProxyFactoryBean.setRefreshStubOnConnectFailure(true);//连接出错的时候自动重连
        rmiProxyFactoryBean.afterPropertiesSet();
        return rmiProxyFactoryBean;
    }

    @Resource(name="rmiUserServiceClient")
    private UserService userService;

    /**
     * hessian没有注册表，不需要设置 serviceName
     */
    @Bean(name = "hessianServiceExporter")
    public HessianServiceExporter hessianServiceExporter(UserService userService) {
        HessianServiceExporter hessianServiceExporter = new HessianServiceExporter();
        hessianServiceExporter.setService(userService);
        hessianServiceExporter.setServiceInterface(UserService.class);
        return hessianServiceExporter;
    }
    /**
     * 需要配置一个URL映射来确保DispatcherServlet把请求转给HessianServiceExporter
     */
    @Bean(name = "handlerMapping")
    public HandlerMapping handlerMapping() {
        SimpleUrlHandlerMapping handlerMapping = new SimpleUrlHandlerMapping();
        Properties mappings = new Properties();
        mappings.setProperty("/user.service", "hessianServiceExporter");
        handlerMapping.setMappings(mappings);
        return handlerMapping;
    }

    @Bean(name = "hessianUserServiceClient")
    public HessianProxyFactoryBean hessianUserServiceClient(){
        HessianProxyFactoryBean proxy = new HessianProxyFactoryBean();
        proxy.setServiceUrl("http://127.0.0.1:8080/user.service");
        proxy.setServiceInterface(UserService.class);
        return proxy;
    }

    @Resource(name="hessianUserServiceClient")
    private UserService userService; 

    /*Http Invoker*/
    @Bean(name = "httpInvokerServiceExporter")
    public HttpInvokerServiceExporter httpInvokerServiceExporter(UserService userService){
        HttpInvokerServiceExporter httpInvokerServiceExporter = new HttpInvokerServiceExporter();
        httpInvokerServiceExporter.setService(userService);
        httpInvokerServiceExporter.setServiceInterface(UserService.class);
        return httpInvokerServiceExporter;
    }
    /**
     * 需要配置一个URL映射来确保DispatcherServlet把请求转给HessianServiceExporter
     */
    @Bean(name = "handlerMapping")
    public HandlerMapping handlerMapping() {
        SimpleUrlHandlerMapping handlerMapping = new SimpleUrlHandlerMapping();
        Properties mappings = new Properties();
        mappings.setProperty("/user.service", "hessianServiceExporter");
        mappings.setProperty("/userInvoker.service", "httpInvokerServiceExporter");
        handlerMapping.setMappings(mappings);
        return handlerMapping;
    }

    @Bean(name = "httpInvokerUserServiceClient")
    public HttpInvokerProxyFactoryBean httpInvokerUserServiceClient(){
        HttpInvokerProxyFactoryBean proxy = new HttpInvokerProxyFactoryBean();
        proxy.setServiceUrl("http://127.0.0.1:8080//userInvoker.service");
        proxy.setServiceInterface(UserService.class);
        return proxy;
    }

    @Resource(name="httpInvokerUserServiceClient")
    private UserService userService;