Eclipse开发XML-RPC程序——入门

    最近想搞分布式系统，查了不少东东，才决定用JAVA，又决定先从XML-RPC开始着手。刚开始找了大半天的资料都是些类同或不适合入门者的文章，好晕。。。后来，改变了关键词，终于找到了一篇，真是柳暗花明又一村啊：）

 开发流程如下：

Installing the development environment

The first step is to install the development environment. In this example our development environment is based on Eclipse IDE and we use Tomcat servlet container. These tools integrate well and are freely available from their vendors.

1. Install JDK 1.4
2. Install Apache Tomcat 4
3. Install Eclipse IDE
4. Install the Tomcat plugin for Eclipse (read the included readme.html!)
   
5. Download the Apache XML-RPC library
6. Start Eclipse
7. Under Window / Preferences / Tomcat, check Tomcat Version 4.1.x and browse to teh Tomcat installation directory; under Tomcat / JVM Settings select the JDK 1.4 or detected jvm in the JRE - dropdown.
8. If you are proficient with Tomcat, we recommend that you clean up all the extra stuff from TOMCAT_HOME/conf/server.xml as this will greatly decrease the startup time. （这个不清楚。。）

Creating a new Web-application project

To create a new web application, we must first set up a new project in Eclipse.

1. Start by creating a new Java Tomcat project from Eclipse: open File / New / Project and select Java / Tomcat project
2. Name the project, check "can update server.xml" and click Finish.
3. Right click the newly created project, select Properties / Tomcat, set the Context name to /xmlrpc
4. Copy xmlrpc-1.2-b1.jar (from the xmlrpc-1.2-b1.zip archive) and place it under Eclipse/workspace/<your project name>/WEB-INF/lib
5. In Eclipse, right click your project and choose Properties, under Java Build Path, on the Libraries-tab, and add the above mentioned file as an external JAR. In the adjoining Order and Export tab, check  xmlrpc-1.2-b1.jar.
6. In the Eclipse resource view, browse to the WEB-INF/lib directory, right click and select Refresh

    我用的是Apache XML-RPC 3。1，下面一个例子：

Server:

public interface ServicesHandler {
 public String execute(String str);
}

public class HelloHandler implements ServicesHandler {

    public String execute(String str){
          return "Hello," + str + "!";
    }
}

 import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import org.apache.xmlrpc.*;
import org.apache.xmlrpc.server.*;
import org.apache.xmlrpc.webserver.*;

public class XmlRpcServicesServlet extends HttpServlet {
 
 private XmlRpcServletServer server;

    public void init(ServletConfig pConfig) throws ServletException {

          super.init(pConfig);

          try {
                // create a new XmlRpcServletServer object
                server = new XmlRpcServletServer();

                // set up handler mapping of XmlRpcServletServer object
                PropertyHandlerMapping phm = new PropertyHandlerMapping();
                phm.addHandler("HelloHandler", HelloHandler.class);                 
                server.setHandlerMapping(phm);

                // more config of XmlRpcServletServer object     
                XmlRpcServerConfigImpl serverConfig = (XmlRpcServerConfigImpl)server.getConfig();
                serverConfig.setEnabledForExtensions(true);
                serverConfig.setContentLengthOptional(false);
          } catch (XmlRpcException e) {
                try {
                      log("Failed to create XmlRpcServer: " + e.getMessage(), e);

                } catch (Throwable ignore) {
                 
                }
                throw new ServletException(e);
          }
    }

   
    public void doPost(HttpServletRequest Request, HttpServletResponse Response)

          throws IOException, ServletException {

          server.execute(Request, Response);
    }
   
    public void doGet(HttpServletRequest Request, HttpServletResponse Response)

    throws IOException, ServletException {

    server.execute(Request, Response);
    }
}

 Client:

import java.io.IOException;

import java.net.MalformedURLException;

import java.util.Vector;

import java.net.URL;

 

import org.apache.xmlrpc.XmlRpcException;

import org.apache.xmlrpc.client.XmlRpcClient;

import org.apache.xmlrpc.client.XmlRpcClientConfigImpl;

 

public class TestClient {

      public static void main(String [] args) throws Exception {

       try {

              // config client

              XmlRpcClientConfigImpl config = new XmlRpcClientConfigImpl();

              config.setServerURL(new URL("http://localhost:8080/XmlRpc/HelloHandler"));      // should be modified according to your configuration of jsp container

              // create a new XmlRpcClient object and bind above config object with it

              XmlRpcClient client = new XmlRpcClient();

              client.setConfig(config);

              // create parameter list

              Vector<String> params = new Vector<String>();

              params.addElement("MY");

              // execute XML-RPC call

              String result = (String) client.execute("HelloHandler.execute", params);                 

              System.out.println(result);

        } catch (MalformedURLException e) {

              System.out.println(e.toString());

        } catch (XmlRpcException e) {

              System.out.println(e.toString());

        } catch (IOException e) {

              e.printStackTrace();

        }

  }
}

在WEB-INF下创建一个配置文件:web.xml:

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

<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN"
"http://java.sun.com/j2ee/dtds/web-app_2_2.dtd">
<web-app>

<servlet>
<servlet-name>XmlRpcServer</servlet-name>
<servlet-class>XmlRpcServicesServlet</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>XmlRpcServer</servlet-name>
<url-pattern>/HelloHandler</url-pattern>
</servlet-mapping>

</web-app>