http://zhuchengzzcc.iteye.com/blog/1534311

?相比WebService，Hessian更簡單、快捷。采用的是二進制RPC協議（Binary），因為采用的是二進制協議，所以它很適合于發送二進制數據。Hessian通常通過Web應用來提供服務，因此非常類似于WebService。只是它不使用SOAP協議。?
??????Hessian通過Servlet提供遠程服務。需要將匹配某個模式的請求映射到Hessian服務。Spring的DispatcherServlet可以完成該功能，DispatcherServlet可將匹配模式的請求轉發到Hessian服務。Hessian的server端提供一個servlet基類, 用來處理發送的請求，而Hessian的這個遠程過程調用，完全使用動態代理來實現的,，推薦采用面向接口編程，因此，Hessian服務建議通過接口暴露。

?

Hessian處理過程示意圖：?
客戶端——>序列化寫到輸出流——>遠程方法（服務器端）——>序列化寫到輸出流 ——>客戶端讀取輸入流——>輸出結果

環境搭建?
Hessian的下載和安裝請按如下步驟進行：?
（1）登http://www.caucho.com/hessian/下載Hessian。?
（2）把Hessian相應的Jar包放到Web應用下，所有的jar文件都應該放在WEB-INF/lib下，該文件也不例外。

?

?

兩種方式?
1.純Hessian?
這種方式主要是適用于工程中沒有適用像spring框架的情況下，好處是配置方便，但是當內容多的情況下，配置的內容很多。

?

?

Java代碼??

package?test;??

??

import?java.util.List;??

??

/**?

?*?@author?zhuc?

?*?@version?2012-5-17?下午9:15:50?

?*/??

public?interface?IService?{??

????/**?

?????*?@param?name?

?????*?@return?

?????*/??

????public?String?sayHello(String?name);??

??????

????/**?

?????*?@return?

?????*/??

????public?Car?getMyCar();??

??????

????/**?

?????*?@return?

?????*/??

????public?List<String>?getList();??

}??

??

??

package?test;??

??

import?java.util.ArrayList;??

import?java.util.List;??

??

import?com.caucho.hessian.server.HessianServlet;??

??

/**?

?*?@author?zhuc?

?*?@version?2012-5-17?下午9:16:35?

?*/??

public?class?ServiceImpl?extends?HessianServlet?implements?IService?{??

??

????/**?

?????*??

?????*/??

????private?static?final?long?serialVersionUID?=?8385639368192939451L;??

??

????@Override??

????public?String?sayHello(String?name)?{??

????????return?"hello:?"?+?name;??

????}??

??

????@Override??

????public?Car?getMyCar()?{??

????????Car?c?=?new?Car();??

????????c.setName("哈哈車");??

????????return?c;??

????}??

??

????@Override??

????public?List<String>?getList()?{??

????????List<String>?list?=?new?ArrayList<String>();??

????????list.add("haha");??

????????list.add("hehe");??

????????return?list;??

????}??

??

}??

??

??

package?test;??

??

import?java.io.Serializable;??

??

/**?

?*?@author?zhuc?

?*?@version?2012-5-17?下午10:29:18?

?*/??

public?class?Car?implements?Serializable?{??

??

????/**?

?????*??

?????*/??

????private?static?final?long?serialVersionUID?=?-1115598660168001267L;??

??

????private?String?name;??

??

????/**?

?????*?@return?the?name?

?????*/??

????public?String?getName()?{??

????????return?name;??

????}??

??

????/**?

?????*?@param?name?the?name?to?set?

?????*/??

????public?void?setName(String?name)?{??

????????this.name?=?name;??

????}??

??

????/**?

?????*?@return?the?serialversionuid?

?????*/??

????public?static?long?getSerialversionuid()?{??

????????return?serialVersionUID;??

????}??

??????

??????

}??

?

?

web.xml的詳細配置

Xml代碼??

<servlet>??

????????<servlet-name>Hello</servlet-name>??

????????<servlet-class>com.caucho.hessian.server.HessianServlet</servlet-class>??

????????<init-param>??

????????????<param-name>home-class</param-name>??

????????????<param-value>test.ServiceImpl</param-value>??

????????</init-param>??

????????<init-param>??

????????????<param-name>home-api</param-name>??

????????????<param-value>test.IService</param-value>??

????????</init-param>??

????????<load-on-startup>1</load-on-startup>??

????</servlet>??

??

????<servlet-mapping>??

????????<servlet-name>Hello</servlet-name>??

????????<url-pattern>/Hello</url-pattern>??

????</servlet-mapping>??

?

客戶端遠程調用服務器端提供的接口，利用的就是Hessian的HessianProxyFactory，來實現遠程代理

?

Java代碼??

package?test;??

??

import?java.net.MalformedURLException;??

import?java.util.List;??

??

import?com.caucho.hessian.client.HessianProxyFactory;??

??

/**?

?*?@author?zhuc?

?*?@version?2012-5-17?下午9:31:14?

?*/??

public?class?ClientTest?{??

??

????/**?

?????*?@param?args?

?????*/??

????public?static?void?main(String[]?args)?{??

????????String?url?=?"http://localhost:8080/Hessian/Hello";??

????????HessianProxyFactory?factory?=?new?HessianProxyFactory();??

????????try?{??

????????????IService?hello?=?(IService)?factory.create(IService.class,?url);??

????????????System.out.println(hello.sayHello("zhuc-no"));??

??

????????????Car?c?=?hello.getMyCar();??

????????????System.out.println(c.getName());??

??

????????????List<String>?list?=?hello.getList();??

????????????for?(String?string?:?list)?{??

????????????????System.out.println(string);??

????????????}??

????????}?catch?(MalformedURLException?e)?{??

????????????e.printStackTrace();??

????????}??

??

????}??

??

}??

?

?

輸出結果，成功

hello: zhuc-no
?哈哈車
?haha
?hehe

?

?

2.Hessian與Spring整合?
相比上一種方式，這個方式就有點麻煩了。Hessian通過Servlet提供遠程服務。需要將匹配某個模式的請求映射到Hessian服務。Spring的DispatcherServlet可以完成該功能，DispatcherServlet可將匹配模式的請求轉發到Hessian服務，web.xml只是定義了“請求轉發器”，該轉發器將匹配/remoting/*的請求截獲，轉發給context的bean處理。而HessianServiceExporter提供bean服務。?
所以Hessian與Spring整合主要就是一下兩個工作：?
1：通過DispatcherServlet來攔截URL請求。?
2：HessianServiceExporter提供bean服務，Spring使用HessianServiceExporter，將一個常規bean導出成Hessian服務。?

?

修改web.xml的詳細配置?

?

Xml代碼??

<servlet>??

????????<servlet-name>remoting</servlet-name>??

????????<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>??

????????<!--?????

????????<init-param>????

????????????<param-name>contextConfigLocation</param-name>????

????????????<param-value>/WEB-INF/remoting-servlet.xml</param-value>????

????????</init-param>????

??????????

?????????在/WEB-INF/增加一個叫servlet-name-servlet.xml配置文件。該文件的命名有一定的規則，??

?????????紅色servlet-name需要和web.xml中的<servlet-name>springhessian</servlet-name>定義的名稱相匹配，??

?????????比如本例子應叫remoting-servlet.xml,這樣簡單也不容易出錯。??

???????????

????????當然該文件也可以自己任意命名。如果是自定義的文件名稱不符合上述默認的規則，??

????????需要在<servlet>中增加<init-param>相關屬性，人為指定加載配置文件，否則會報錯??

?????????-->???

????????<load-on-startup>1</load-on-startup>??

????</servlet>??

????<servlet-mapping>??

????????<servlet-name>remoting</servlet-name>??

????????<url-pattern>/remoting/*</url-pattern>??

????</servlet-mapping>??

?

?

配置remoting-servlet.xml文件，將其放于/WEB-INF/下

?

Xml代碼??

<?xml?version="1.0"?encoding="UTF-8"?>??

<beans?xmlns="http://www.springframework.org/schema/beans"??

????xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"?xmlns:context="http://www.springframework.org/schema/context"??

????xmlns:aop="http://www.springframework.org/schema/aop"?xmlns:tx="http://www.springframework.org/schema/tx"??

????xsi:schemaLocation="http://www.springframework.org/schema/beans???

???????????http://www.springframework.org/schema/beans/spring-beans-2.5.xsd??

???????????http://www.springframework.org/schema/context??

???????????http://www.springframework.org/schema/context/spring-context-2.5.xsd??

???????????http://www.springframework.org/schema/aop?http://www.springframework.org/schema/aop/spring-aop-2.5.xsd??

???????????http://www.springframework.org/schema/tx?http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">??

??

????<!--?定義普通bean實例?-->??

????<bean?id="serviceImpl"?class="test.ServiceImpl"?/>??

??

????<!--?使用HessianServiceExporter?將普通bean導出成Hessian服務?-->??

????<bean?name="/hessianCommentService"??

????????class="org.springframework.remoting.caucho.HessianServiceExporter">??

????????<!--?需要導出的目標bean?-->??

????????<property?name="service"?ref="serviceImpl"?/>??

????????<!--?Hessian服務的接口?-->??

????????<property?name="serviceInterface"?value="test.IService"?/>??

????</bean>??

</beans>??

?

客戶端定義一個remoting-client.xml文件

?

Xml代碼??

<?xml?version="1.0"?encoding="UTF-8"?>??

<beans?xmlns="http://www.springframework.org/schema/beans"??

????xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"?xmlns:context="http://www.springframework.org/schema/context"??

????xmlns:aop="http://www.springframework.org/schema/aop"?xmlns:tx="http://www.springframework.org/schema/tx"??

????xsi:schemaLocation="http://www.springframework.org/schema/beans???

???????????http://www.springframework.org/schema/beans/spring-beans-2.5.xsd??

???????????http://www.springframework.org/schema/context??

???????????http://www.springframework.org/schema/context/spring-context-2.5.xsd??

???????????http://www.springframework.org/schema/aop?http://www.springframework.org/schema/aop/spring-aop-2.5.xsd??

???????????http://www.springframework.org/schema/tx?http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">??

??

????<bean?id="myServiceClient"??

????????class="org.springframework.remoting.caucho.HessianProxyFactoryBean">??

????????<property?name="serviceUrl">??

????????????<value>http://localhost:8080/Hessian/remoting/hessianCommentService</value>??

????????</property>??

????????<property?name="serviceInterface">??

????????????<value>test.IService</value>??

????????</property>??

????</bean>??

??

</beans>??

?

?

客戶端調用

?

?

Java代碼??

package?spring;??

??

import?java.util.List;??

??

import?org.springframework.context.ApplicationContext;??

import?org.springframework.context.support.ClassPathXmlApplicationContext;??

??

import?test.Car;??

import?test.IService;??

??

/**?

?*?@author?zhuc?

?*?@version?2012-5-17?下午9:59:31?

?*/??

public?class?ClientTest?{??

??

????/**?

?????*?@param?args?

?????*/??

????public?static?void?main(String[]?args)?{??

????????ApplicationContext?context?=?new?ClassPathXmlApplicationContext(??

????????????????"spring/remoting-client.xml");??

????????IService?hello?=?(IService)?context.getBean("myServiceClient");??

????????System.out.println(hello.sayHello("zhuc-spring"));??

??

????????Car?c?=?hello.getMyCar();??

????????System.out.println(c.getName());??

??

????????List<String>?list?=?hello.getList();??

????????for?(String?string?:?list)?{??

????????????System.out.println(string);??

????????}??

????}??

??

}??

?

?

輸出結果同上。

?

注：上述spring方式，客戶端中的請求URL

http://localhost:8080/Hessian/remoting/hessianCommentService?中的hessianCommentService需要和remoting-servlet.xml配置中HessianServiceExporter的bean name相同，否則將會找不到server端

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