【RPC】使用Hessian构建RPC的简单示例

服务接口和实现

public interface HelloService {
    // 服务方法
    String sayHello(String name);
}

public class HelloServiceImpl implements HelloService {

    public String sayHello(String name) {
        return "RPC > Hello , " + name;
    }

}

Maven引用

<Hessian.version>4.0.38</Hessian.version>
<!--hessian start -->
  <dependency>
    <groupId>com.caucho</groupId>
    <artifactId>hessian</artifactId>
    <version>${Hessian.version}</version>
  </dependency>
<!--hessian end -->

web.xml配置

配置HessianServlet

<!--HessianServlet start -->
<servlet>
  <!-- 配置 HessianServlet -->
  <servlet-name>helloService</servlet-name>
  <servlet-class>com.caucho.hessian.server.HessianServlet</servlet-class>

  <!-- 配置接口的具体实现类 -->
  <init-param>
    <param-name>service-class</param-name>
    <param-value>com.ll.rpc.HelloServiceImpl</param-value>
  </init-param>
</servlet>
<!-- 映射 HessianServlet的访问URL地址 -->
<servlet-mapping>
  <servlet-name>helloService</servlet-name>
  <url-pattern>/helloService</url-pattern>
</servlet-mapping>
<!--HessianServlet end -->

Tomcat配置

1. 下载Tomcat：使用版本6.0.51;
2. 配置环境变量:CATALINA_HOME=D:\xxx\apache-tomcat-6.0.51;
3. 配置Javaweb为tomcat默认项目:
   修改server.xml，添加：可参见​【Jersey】基于Jersey构建Restful Web应用

<Context path="" docBase="D:\xxx\target\Javaweb" debug="0" reloadable="true"/>

Clinet客户端实现

package com.ll.rpc;

import java.net.MalformedURLException;

import com.caucho.hessian.client.HessianProxyFactory;

public class Client {
  public static void main(String[] args) {
    // 远程Hessian服务
    String url = "http://localhost:8080/helloService";
    try {
      // 利用hessianProxyFactory.create()方法创建一个代理对象
      HelloService helloService = (HelloService) (new HessianProxyFactory()
          .create(HelloService.class, url));

      // 调用服务方法
      System.out.println(helloService.sayHello("sssppp"));
    } catch (MalformedURLException e) {

    }
  }
}

输出结果测试：

RPC > Hello , sssppp

其他

参考链接：

常用RPC框架及一个简单的RPC框架实现

完整的web.xml如下：

可参见【Jersey】基于Jersey构建Restful Web应用

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
  version="2.4">
  <display-name>Java Web</display-name>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>

  <!--Spring 文件路径 -->
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:conf/beans/beans-*.xml</param-value>
  </context-param>

  <!-- spring上下文监听器 -->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <listener>
    <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
  </listener>

  <!-- 解决中文乱码 -->
  <filter>
    <filter-name>SetCharacterEncoding</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
    <init-param>
      <param-name>forceEncoding</param-name>
      <param-value>false</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>SetCharacterEncoding</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

  <!-- jersey Servlet start -->
  <servlet>
    <servlet-name>rest-inside</servlet-name>
    <servlet-class>com.sun.jersey.spi.spring.container.servlet.SpringServlet</servlet-class>
    <init-param>
      <param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
      <param-value>true</param-value>
    </init-param>
    <!-- 设置Restful实例的位置 -->
    <init-param>
      <param-name>com.sun.jersey.config.property.packages</param-name>
      <param-value>com.ll.jersey</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>rest-inside</servlet-name>
    <url-pattern>/jersey/rest/*</url-pattern>
  </servlet-mapping>
  <!-- jersey Servlet end -->

  <!--HessianServlet start -->
  <servlet>
    <!-- 配置 HessianServlet -->
    <servlet-name>helloService</servlet-name>
    <servlet-class>com.caucho.hessian.server.HessianServlet</servlet-class>

    <!-- 配置接口的具体实现类 -->
    <init-param>
      <param-name>service-class</param-name>
      <param-value>com.ll.rpc.HelloServiceImpl</param-value>
    </init-param>
  </servlet>
  <!-- 映射 HessianServlet的访问URL地址 -->
  <servlet-mapping>
    <servlet-name>helloService</servlet-name>
    <url-pattern>/helloService</url-pattern>
  </servlet-mapping>
  <!--HessianServlet end -->

</web-app>