hessian学习

声明：转自http://www.cnblogs.com/yjmyzz/p/hessian-helloworld.html，感谢！

hessian是一个采用二进制格式传输的服务框架，相对传统soap web service，更轻量，更快速。官网地址：http://hessian.caucho.com/

目前已经支持N多语言，包括：java/c#/flex/php/ruby...

maven的依赖项如下：

1 <dependency>2     <groupId>com.caucho</groupId>3     <artifactId>hessian</artifactId>4     <version>4.0.37</version>5 </dependency>

入门示例：

一、服务端开发

1.1 先建服务接口

1 package yjmyzz.cnblogs.com.service;2 3 public interface HelloService {4     5     public String helloWorld(String message);6 }

1.2 提供服务实现

 1 package yjmyzz.cnblogs.com.service.impl; 2  3 import yjmyzz.cnblogs.com.service.HelloService; 4  5 public class HelloServiceImpl implements HelloService { 6  7     @Override 8     public String helloWorld(String message) { 9         return "hello," + message;10     }11 12 }

1.3 修改web.xml

 1 <!DOCTYPE web-app PUBLIC 2  "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" 3  "http://java.sun.com/dtd/web-app_2_3.dtd" > 4  5 <web-app> 6     <display-name>hessian-showcase</display-name> 7  8     <welcome-file-list> 9         <welcome-file>index.jsp</welcome-file>10     </welcome-file-list>11 12     <servlet>13         <servlet-name>hessian-service</servlet-name>14         15         <servlet-class>16             com.caucho.hessian.server.HessianServlet17         </servlet-class>18         19         <init-param>            20             <param-name>home-class</param-name>            21             <param-value>22                 <!-- 服务实现类 -->23                 yjmyzz.cnblogs.com.service.impl.HelloServiceImpl24             </param-value>25         </init-param>26 27         <init-param>            28             <param-name>home-api</param-name>29             <!-- 服务接口 -->30             <param-value>yjmyzz.cnblogs.com.service.HelloService</param-value>31         </init-param>32 33     </servlet>34 35     <servlet-mapping>36         <servlet-name>hessian-service</servlet-name>37         <url-pattern>/hessian</url-pattern>38     </servlet-mapping>39 40 </web-app>

部署到tomcat或其它web容器中即可。
1.4 导出服务接口jar包

最终服务是提供给客户端调用的，客户端必须知道服务的接口信息（包括接口方法中的传输dto定义），所以得将这些java文件导出成jar，提供给调用方。

方法很简单：eclipse中在接口package（包括dto对应的package）上右击，选择Export

再选择Jar File

 

二、客户端调用

同样先添加maven的hessian依赖项，同时引入上一步导出的服务接口jar包，然后参考下面的示例代码：

 1 import java.net.MalformedURLException; 2 import org.junit.Test; 3 import yjmyzz.cnblogs.com.service.HelloService; 4 import com.caucho.hessian.client.HessianProxyFactory; 5  6  7 public class ServiceTest { 8     @Test 9     public void testService() throws MalformedURLException {        10 11         String url = "http://localhost:8080/hessian-showcase/hessian";12         System.out.println(url);13         14         HessianProxyFactory factory = new HessianProxyFactory();15         HelloService helloService = (HelloService) factory.create(HelloService.class, url);16         System.out.println(helloService.helloWorld("jimmy"));17 18     }19 }

 

三、与Spring的整合

spring-web包里提供的org.springframework.remoting.caucho.HessianServiceExporter类，可以将普通方法导出成hessian服务。关键是解决org.springframework.web.servlet.DispatcherServlet的url访问路径问题，一般情况下，我们是这样配置的

 1     <!-- spring mvc --> 2     <servlet> 3         <servlet-name>appServlet</servlet-name> 4         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> 5         <init-param> 6             <param-name>contextConfigLocation</param-name> 7             <param-value>classpath:servlet-context.xml</param-value> 8         </init-param> 9         <load-on-startup>1</load-on-startup>10         <async-supported>true</async-supported>11     </servlet>12 13     <servlet-mapping>14         <servlet-name>appServlet</servlet-name>15         <url-pattern>/</url-pattern>16     </servlet-mapping>

这是spring mvc的入口，拦截所有访问路径，可以把这一节再复制一份，追加在后面，只不过url-pattern指定成特定的规则

 1 <!-- spring mvc --> 2     <servlet> 3         <servlet-name>appServlet</servlet-name> 4         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> 5         <init-param> 6             <param-name>contextConfigLocation</param-name> 7             <param-value>classpath:servlet-context.xml</param-value> 8         </init-param> 9         <load-on-startup>1</load-on-startup>10         <async-supported>true</async-supported>11     </servlet>12 13     <servlet-mapping>14         <servlet-name>appServlet</servlet-name>15         <url-pattern>/</url-pattern>16     </servlet-mapping>17     18     19     <!-- hessian -->20     <servlet>21         <servlet-name>hessianServlet</servlet-name>22         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>23         <init-param>24             <param-name>contextConfigLocation</param-name>25             <param-value>classpath:hessian-context.xml</param-value>26         </init-param>27         <load-on-startup>1</load-on-startup>        28     </servlet>29 30     <servlet-mapping>31         <servlet-name>hessianServlet</servlet-name>32         <url-pattern>/hessian/*</url-pattern>33     </servlet-mapping>

这样，所有以/hessian/开头的访问路径，约定成hessian服务地址，详细配置在hessian-context.xml中，内容如下：

 1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" 4     xmlns:context="http://www.springframework.org/schema/context" 5     xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd 6         http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd 7         http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> 8  9     10     <bean id="helloServiceImpl" class="com.cnblogs.yjmyzz.service.hessian.support.HelloServiceImpl" />11     12     <!-- 使用HessianServiceExporter 将普通bean导出成Hessian服务 -->13     <bean name="/service"14         class="org.springframework.remoting.caucho.HessianServiceExporter">        15         <property name="service" ref="helloServiceImpl" />16         <!-- Hessian服务的接口 -->17         <property name="serviceInterface" value="com.cnblogs.yjmyzz.service.hessian.HelloService" />18     </bean>19 20 </beans>

这样，就能直接以http://localhost:8080/spring-mvc4-rest/hessian/service 发布hessian服务了

再来看看客户端如何整合，类似的，我们需要一个配置文件，比如：hessian-client.xml，内容如下：

 1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" 4     xsi:schemaLocation="http://www.springframework.org/schema/beans  5         http://www.springframework.org/schema/beans/spring-beans.xsd 6         http://www.springframework.org/schema/context  7         http://www.springframework.org/schema/context/spring-context.xsd"> 8  9     <bean id="hessianClient"10         class="org.springframework.remoting.caucho.HessianProxyFactoryBean">11         <property name="serviceUrl">12             <value>http://localhost:8080/spring-mvc4-rest/hessian/service</value>13         </property>14         <property name="serviceInterface">15             <value>com.cnblogs.yjmyzz.service.hessian.HelloService</value>16         </property>17     </bean>18 19 </beans>

调用示例：

 1 package com.cnblogs.yjmyzz.test; 2 import java.net.MalformedURLException; 3  4 import org.junit.Test; 5 import org.springframework.context.ApplicationContext; 6 import org.springframework.context.support.ClassPathXmlApplicationContext; 7  8 import com.cnblogs.yjmyzz.service.hessian.HelloService; 9 10 public class HessianServiceTest {    11     @SuppressWarnings("resource")12     @Test13     public void testService() throws MalformedURLException {14         ApplicationContext context = new ClassPathXmlApplicationContext(15                 "hessian-client.xml");16         HelloService hello = (HelloService) context.getBean("hessianClient");17         System.out.println(hello.helloWorld("jimmy.yang"));18     }19 }

示例源码地址：http://code.taobao.org/p/spring-mvc4-rest/src/