探讨:使用httpClient在客户端与服务器端传输对象参数的详解

本篇文章是对使用httpClient在客户端与服务器端传输对象参数进行了详细的分析介绍，需要的朋友参考下

昨天把httpClient的源代码下载来看了一下。 稍微跟踪了一下,最终还是使用java.net包的东西.不过封装的实在是漂亮.写程序方便多了。不过还是建议最好先熟悉net包下的东西.为了测试写了个在客户端和服务器段传对象的代码. 简单的传递了一个字符串. 如果复杂点可以传其他的对象,在参数里给出class name之类的信息.服务器端就可以使用反射来做一些实用的操作了。

客户端:

import java.io.IOException;import java.io.Serializable;import org.apache.commons.httpclient.HttpClient;import org.apache.commons.httpclient.methods.InputStreamRequestEntity;import org.apache.commons.httpclient.methods.PostMethod;import org.apache.commons.httpclient.methods.RequestEntity;public class MyTest{    /**     * @param args     * @throws IOException     * @throws ClassNotFoundException     */    public static void main(String[] args) throws IOException, ClassNotFoundException    {        String url = "http://localhost:8084/system/linantest";        String queryString = "test=hello";        String inputObj = " boy!";        Serializable s = getObjFromServer(url, queryString, inputObj);        System.out.println(s.toString());    }    /**     * @param url     * @param queryString 类似a=b&c=d 形式的参数     *     * @param inputObj   发送到服务器的对象。     *         * @return 服务器返回到客户端的对象。     * @throws IOException     */    public static Serializable getObjFromServer(String url, String queryString, Serializable inputObj) throws IOException    {        HttpClient client = new HttpClient();        PostMethod post = new PostMethod(url);        post.setQueryString(queryString);        post.setRequestHeader("Content-Type", "application/octet-stream");        java.io.ByteArrayOutputStream bOut = new java.io.ByteArrayOutputStream(1024);        java.io.ByteArrayInputStream bInput = null;        java.io.ObjectOutputStream out = null;        Serializable returnObj = null;        try        {            out = new java.io.ObjectOutputStream(bOut);            out.writeObject(inputObj);            out.flush();            out.close();            out = null;            bInput = new java.io.ByteArrayInputStream(bOut.toByteArray());            RequestEntity re = new InputStreamRequestEntity(bInput);            post.setRequestEntity(re);            client.executeMethod(post);            java.io.InputStream in = post.getResponseBodyAsStream();            java.io.ObjectInputStream oInput = new java.io.ObjectInputStream(in);            returnObj = (Serializable) oInput.readObject();            oInput.close();            oInput = null;        }        catch (IOException e)        {            // TODO Auto-generated catch block            e.printStackTrace();        }        catch (ClassNotFoundException e)        {            // TODO Auto-generated catch block            e.printStackTrace();        }        finally        {            if (out != null)            {                out.close();                out = null;            }            if (bInput != null)            {                bInput.close();                bInput = null;            }            //释放连接            post.releaseConnection();        }        return returnObj;    }}

服务器端的servlet

package test.li;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.openjweb.eai.adapter.TimerDBAdapter;public class TestServlet extends HttpServlet{    public TestServlet()    {        super();    }    /**     * Destruction of the servlet. <br>     */    public void destroy()    {        super.destroy(); // Just puts "destroy" string in log        // Put your code here    }    /**     * The doGet method of the servlet. <br>     *     * This method is called when a form has its tag value method equals to get.     *     * @param request     *            the request send by the client to the server     * @param response     *            the response send by the server to the client     * @throws Exception     */    public void doGet(HttpServletRequest request, HttpServletResponse response)    {        String test = request.getParameter("test");        java.io.ObjectInputStream oi = null;        java.io.ObjectOutputStream ot = null;        try        {            oi = new java.io.ObjectInputStream(request.getInputStream());            Object o = oi.readObject();            oi.close();            oi = null;            String outObj = test + o.toString();            ot = new java.io.ObjectOutputStream(response.getOutputStream());            ot.writeObject(outObj);            ot.flush();            ot.close();            ot = null;        }        catch (IOException e)        {            // TODO Auto-generated catch block            e.printStackTrace();        }        catch (ClassNotFoundException e)        {            // TODO Auto-generated catch block            e.printStackTrace();        }        finally        {            try            {                if (oi != null)                {                    oi.close();                    oi = null;                }                if (ot != null)                {                    ot.close();                    ot = null;                }            }            catch (IOException e)            {                // TODO Auto-generated catch block                e.printStackTrace();            }        }        }    /**     * The doPost method of the servlet. <br>     *     * This method is called when a form has its tag value method equals to     * post.     *     * @param request     *            the request send by the client to the server     * @param response     *            the response send by the server to the client     * @throws ServletException     *             if an error occurred     * @throws IOException     *             if an error occurred     */    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException    {        doGet(request, response);    }    /**     * Initialization of the servlet. <br>     *     * @throws ServletException     *             if an error occure     */    public void init() throws ServletException    {        // Put your code here    }}