软件环境： JDK1.6、Spring3.0.5、Hibernate3.2.2、Hessian3.1.5

参考Spring Documents：中文|英文

服务端：

###1. remoting-servlet.xml <!-- 扫描并加注HessianService使用的bean --> <context:annotation-config /> <!-- <context:component-scan base-package="com.**" /> -->

<!--Hessian 启动BeanNameMapping 映射功能,以httpRequest作为处理Adapter-->
<!-- <beanclass="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"><property name="defaultHandler" ref="httpRequestHandlerAdapter" />
</bean> --><!-- Hessian 方式以Http进行传递 -->
<!-- <bean id="httpRequestHandlerAdapter" class="org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter" /> --><!-- 解决Hibernate实体对象bean中集合对象延迟加载lazyLoad，导致Hessian客户端抛出no session or session closed异常的问题 -->
<bean id="lazySerializer" class="com.test.webservice.LazyHibernateSerializerFactory"></bean><!-- UnifiedUser -->
<bean id="unifiedUserService" class="com.test.manager.impl.UnifiedUserServiceImpl" />
<bean name="/UnifiedUserService" class="org.springframework.remoting.caucho.HessianServiceExporter"><property name="serializerFactory" ref="lazySerializer"/><property name="service" ref="unifiedUserService" /><property name="serviceInterface" value="com.test.manager.UnifiedUserService"/>
</bean>

###2. LazyHibernateSerializerFactory实现
参考: https://github.com/resthub/spring-amqp-hessian/issues/5

引用: http://code.google.com/p/rich-hibernate-lazy/wiki/HessianWithLazyHibernate

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Set;import org.hibernate.Hibernate;
import org.hibernate.collection.PersistentList;
import org.hibernate.collection.PersistentMap;
import org.hibernate.collection.PersistentSet;import com.caucho.hessian.io.AbstractHessianOutput;
import com.caucho.hessian.io.CollectionSerializer;
import com.caucho.hessian.io.HessianProtocolException;
import com.caucho.hessian.io.JavaSerializer;
import com.caucho.hessian.io.MapSerializer;
import com.caucho.hessian.io.Serializer;
import com.caucho.hessian.io.SerializerFactory;/*** 处理：Hessian远程调用时，对象序列化hibernate实体bean中集合对象延迟加载问题 ，*         采取将集合对象替换为空集合。* **/
public class LazyHibernateSerializerFactory extends SerializerFactory {public static   String versionString = org.hibernate.Version.getVersionString();@Overridepublic Serializer getSerializer(Class cls) throws HessianProtocolException {try {if(versionString.startsWith("3") &&Class.forName("org.hibernate.collection.PersistentCollection").isAssignableFrom(cls)){return new LazySerializerForHibernate3(cls); }else if(versionString.startsWith("4") &&   Class.forName("org.hibernate.collection.spi.PersistentCollection").isAssignableFrom(cls)){return new LazySerializerForHibernate4(cls); }} catch (ClassNotFoundException e) {e.printStackTrace();}return super.getSerializer(cls);}
}class LazySerializerForHibernate3 extends JavaSerializer {public LazySerializerForHibernate3(Class cls) {super(cls);}CollectionSerializer collectionSeiralizer = new CollectionSerializer();MapSerializer mapSerializer = new MapSerializer();/*** @Title: writeObject* @Description: TODO(override hessian write)* @param @param object* @param @param out* @param @throws IOException* @return void* @throws*/@SuppressWarnings("unchecked")@Overridepublic void writeObject(Object object, AbstractHessianOutput out)throws IOException {boolean ifHaveInit = Hibernate.isInitialized(object);Object obj = convertPersistent(object);if (ifHaveInit && object!=null) {out.writeObject(obj);  out.flush();return;}if (PersistentMap.class.isAssignableFrom(object.getClass())) {mapSerializer.writeObject(new HashMap(), out);} else {collectionSeiralizer.writeObject(new ArrayList(), out);}}@SuppressWarnings("unchecked")public static List convertListFromPersistentList(PersistentList plist) {List list = new ArrayList();if (plist != null) {for (int i = 0; i < plist.size(); i++) {list.add(plist.get(i));}}return list;}@SuppressWarnings("unchecked")public static Set convertSetFromPersistentSet(PersistentSet pset){Set set = new HashSet();if (pset != null) {for (int i = 0; i < pset.size(); i++) {set.add(pset.toArray()[i]);}}return set;}public static Object convertPersistent(Object obj){if(obj.getClass().isAssignableFrom(PersistentSet.class)){return convertSetFromPersistentSet((PersistentSet)obj);}else if (obj.getClass().isAssignableFrom(PersistentList.class)){return convertListFromPersistentList((PersistentList)obj);}else{return obj;}}
}class LazySerializerForHibernate4 extends JavaSerializer {public LazySerializerForHibernate4(Class cls) {super(cls);}CollectionSerializer collectionSeiralizer = new CollectionSerializer();MapSerializer mapSerializer = new MapSerializer();/*** @Title: writeObject* @Description: TODO(override hessian write)* @param @param object* @param @param out* @param @throws IOException* @return void* @throws*/@SuppressWarnings("unchecked")@Overridepublic void writeObject(Object object, AbstractHessianOutput out)throws IOException {boolean ifHaveInit = Hibernate.isInitialized(object);if (ifHaveInit) {out.writeObject(object);out.flush();return;}try {if (Class.forName("org.hibernate.collection.internal.PersistentMap").isAssignableFrom(object.getClass())) {mapSerializer.writeObject(new HashMap(), out);} else {collectionSeiralizer.writeObject(new ArrayList(), out);}} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}}
}

###3. web.xml 中添加

<filter><filter-name>osivFilter</filter-name><filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>
</filter><!-- Hessian --><!-- 解决 Hibernate session 在Hessian客户端序列化对象前提前关闭问题 -->
<filter-mapping><filter-name>osivFilter</filter-name><url-pattern>/remoting/*</url-pattern>
</filter-mapping><!-- Hessian -->
<servlet><servlet-name>hessian</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><init-param><param-name>contextConfigLocation</param-name><param-value>/WEB-INF/config/application-context.xml,/WEB-INF/config/remoting-servlet.xml</param-value></init-param>
</servlet>
<servlet-mapping><servlet-name>hessian</servlet-name><url-pattern>/remoting/*</url-pattern>
</servlet-mapping>

客户端：

###1. HessianClient.java

<!-- lang: java -->
import com.caucho.hessian.client.HessianProxyFactory;
import service.UnifiedUserMng;public class HessianClient {public static void main(String[] args) throws Exception {// 远程调用地址String url = "http://localhost:8080/remoting/UnifiedUserService";// 默认写法HessianProxyFactory factory = new HessianProxyFactory(); // 实例化UnifiedUserService base = (UnifiedUserService) factory.create(UnifiedUserMng.class, url);// 调用接口，并打印结果System.out.println(base.getByUsername("admin").getEmail());}
}

总结

Hibernate抛出no session or session closed原因：Hessian调用服务器服务，序列化Hibernate持久化对象中集合对象(Set)时，session已经关闭。参考