Java应用程序与Web服务器交互

1、服务端的代码如下(需要javax.servlet.jar)：

package com.lanp.servlet;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class HandlerHttpRequestServlet extends HttpServlet {private static final long serialVersionUID = 1L;@Overrideprotected void doGet(HttpServletRequest arg0, HttpServletResponse arg1)throws ServletException, IOException {super.doGet(arg0, arg1);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {String username =req.getParameter("username");          //获取username所对应的value        String password =req.getParameter("password");           //获取password所对应的value        System.out.println("The received username and password is: " + username + "/" +password);                // 向请求端发回反馈信息        PrintWriter out =resp.getWriter();        out.print("OK");        out.flush();        out.close();                super.doPost(req, resp);}}

 

2、在Tomcat的webapps文件夹下新建一个JavaApp的文件夹，在JavaApp下新建一个WEB-INF文件夹，在WEB-INF下新建lib文件夹和classes文件夹，在WEB-INF下新建一个web.xml文件。

3、lib文件夹下放commons-logging-1.0.4.jar和commons-logging-1.0.4.jar。

4、classes文件夹下放HandlerHttpRequestServlet.class文件。

5、web.xml文件的内容如下：

<?xml version="1.0" encoding="UTF-8"?><web-app id="WebApp_ID" version="2.4" 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"><display-name>JavaApp</display-name> <servlet>         <servlet-name>JavaAppAervletUpLoad</servlet-name>          <servlet-class>com.lanp.servlet.HandlerHttpRequestServlet</servlet-class>    </servlet>     <servlet-mapping>            <servlet-name>JavaAppAervletUpLoad</servlet-name>         <url-pattern>/upload</url-pattern>      </servlet-mapping><welcome-file-list><welcome-file>index.html</welcome-file><welcome-file>index.htm</welcome-file><welcome-file>index.jsp</welcome-file><welcome-file>default.html</welcome-file><welcome-file>default.htm</welcome-file><welcome-file>default.jsp</welcome-file></welcome-file-list></web-app>

6、Java应用程序代码如下：

package com.lanp;import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import java.net.HttpURLConnection;import java.net.URL;/** * Java应用程序 * @author LanP * @since 2011-11-1 22:36 * @version V1.0 */public class JavaApp {public static void main(String[] args) throws Exception {// 服务地址        URL url = new URL("http://127.0.0.1:8080/JavaApp/upload");        // 设定连接的相关参数        HttpURLConnection connection= (HttpURLConnection) url.openConnection();        connection.setDoOutput(true);        connection.setRequestMethod("POST");        OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(), "UTF-8");                // 向服务端发送key = value对        out.write("username=lanp&password=lanpiao");        out.flush();        out.close();                // 获取服务端的反馈        String strLine="";        String strResponse ="";        InputStream in =connection.getInputStream();        BufferedReader reader = new BufferedReader(new InputStreamReader(in));        while((strLine =reader.readLine()) != null)        {                 strResponse +=strLine +"\n";        }        System.out.print(strResponse);}}

7、先启动Tomcat后运行JavaApp。

 

OK，TKS！