httpclient笔记

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FP 浏览器 Apache

Jakarta的httpclient3.1是最新版本，项目中需要用程序模拟浏览器的GET和POST动作。在使用过程中遇到不少问题。
1. 带附件的POST提交
最开始都是使用MultipartPostMethod这个类，现在已经废弃这个类了。API说明：Deprecated. Use MultipartRequestEntity in conjunction with PostMethod instead. 使用PostMethod可以实现的功能，就没有必要再弄一个MultipartPostMethod了。下面是一段最简单的示例：

PostMethod post = new PostMethod();
        NameValuePair[] pairs = new NameValuePair[2];
        pairs[0] = new NameValuePair("para1", "value1");
        pairs[0] = new NameValuePair("para2", "value2");
        post.setRequestBody(pairs);
        HttpClient client = new HttpClient();
        try {
            client.executeMethod(post);
        } catch (HttpException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

这是针对一般的form形式的提交，而且这个form里面不带附件的。如果带附件，那么这种方法就不起作用，附件上传的参数和普通参数无法一同在服务器获取到。org.apache.commons.httpclient.methods.multipart 这个包就是为处理文件上传这种多形式参数的情况的。最主要的类是Part（代表一种post object），它有二个比较重要的子类：FilePart和StringPart，一个是文件的参数，另一个就是普通的文本参数。它的典型使用方法如下：

String url = "http://localhost:8080/HttpTest/Test";
         PostMethod postMethod = new PostMethod(url);
         
         StringPart sp = new StringPart("TEXT", "testValue");
         FilePart fp = new FilePart("file", "test.txt", new File("./temp/test.txt"));
         
         MultipartRequestEntity mrp= new MultipartRequestEntity(new Part[]{sp, fp}, postMethod
                 .getParams());
         postMethod.setRequestEntity(mrp);
         
         //执行postMethod
         HttpClient httpClient = new HttpClient();
         try {
            httpClient.executeMethod(postMethod);
        } catch (HttpException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

在第二行PostMethod postMethod = new PostMethod();后面，有人说需要使用postMehtod.setRequestHeader("Content-type", "multipart/form-data"); Content-type的请求类型进行更改。但是我在使用过程没有加上这一句，查了一下httpCleint的默认Content-type是 application/octet-stream。应该是没有影响的。对于MIME类型的请求，httpclient建议全用 MulitPartRequestEntity进行包装，就是上面的用法。

2. 参数中文的处理问题
httpclient的默认编码都是ISO-8859-1，那肯定就无法支持中文参数了。引用一下这篇文章：http://thinkbase.net/w/main/Wiki?HttpClient+POST+%E7%9A%84+UTF-8+%E7%BC%96%E7%A0%81%E9%97%AE%E9%A2%98 ，按照作者的说法，就可以正常解决中文编码的问题。其中最关键的是修改EncodingUtil这个类的一个方法实现。另外，FilePart和 StringPart的构造方法都有一个带编码指定的参数，为了减少问题的出现，建议所有的都带上统一的编码，包括 postMethod.getParams()。示例如下：

String url = "http://localhost:8080/HttpTest/Test";
         PostMethod postMethod = new PostMethod(url);
         
         StringPart sp = new StringPart("TEXT", "testValue", "GB2312");
         FilePart fp = new FilePart("file", "test.txt", new File("./temp/test.txt"), null, "GB2312");
         
         postMethod.getParams().setContentCharset("GB2312");
         MultipartRequestEntity mrp= new MultipartRequestEntity(new Part[]{sp, fp}, postMethod
                 .getParams());
         postMethod.setRequestEntity(mrp);
         
         //执行postMethod
         HttpClient httpClient = new HttpClient();
         try {
            httpClient.executeMethod(postMethod);
        } catch (HttpException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

不多说了，直接上示例：

A服务器：

msURL为：http://192.168.7.203:8080

Java代码

  1. /**
   2.      * 发送文件到另一台服务器B
   3.      *  
   4.      * @param File file 附件
   5.      * @param serviceType服务类型
   6.      * @param spId id
   7.      * @return
   8.      */  
   9.     public String sendApply(File file, String serviceType, String spId) {  
  10.         String fromAgentResult = "";  
  11.         HttpClient client = new HttpClient();  
  12.         PostMethod filePost = new PostMethod(msUrl+"?serviceType="+serviceType+"&spId="+spId+"&type=menu");  
  13. //       MultipartPostMethod filePost = new MultipartPostMethod(msUrl);  
  14.         // 若上传的文件比较大 , 可在此设置最大的连接超时时间   
  15.          client.getHttpConnectionManager(). getParams().setConnectionTimeout(8000);    
  16.   
  17.         try {  
  18.   
  19.             FilePart fp = new FilePart(file.getName(), file);  
  20.             MultipartRequestEntity mrp= new MultipartRequestEntity(new Part[]{fp}, filePost.getParams());  
  21.             filePost.setRequestEntity(mrp);  
  22.   
  23.             //使用系统提供的默认的恢复策略  
  24.             filePost.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,  
  25.                 new DefaultHttpMethodRetryHandler());  
  26.   
  27.             int httpStat = client.executeMethod(filePost);  
  28.             System.out.println("httpStat----"+httpStat);  
  29.             if (!(httpStat == HttpStatus.SC_OK)) {  
  30.                 fromAgentResult = "connected fail:" + httpStat;  
  31.             } else if (httpStat == HttpStatus.SC_OK) {  
  32.                   
  33.                 try {  
  34.                     DocumentBuilderFactory factory = DocumentBuilderFactory  
  35.                             .newInstance();  
  36.                     DocumentBuilder builder = factory.newDocumentBuilder();  
  37.                     Document doc = builder  
  38.                             .parse(filePost.getResponseBodyAsStream());  
  39.                     doc.normalize();  
  40.                     // NodeList optypeNL= doc.getElementsByTagName("optype");  
  41.                     NodeList resultNL = doc.getElementsByTagName("result");  
  42.                     // fromAgentOptype=  
  43.                     // optypeNL.item(0).getFirstChild().getNodeValue();  
  44.                     fromAgentResult = resultNL.item(0).getFirstChild()  
  45.                             .getNodeValue();  
  46.                     System.out.println("发送请求完毕，接收状态："+fromAgentResult);  
  47.                 } catch (Exception e) {  
  48.                     e.printStackTrace();  
  49.                 }  
  50.             }  
  51.         } catch (HttpException e) {  
  52.             // TODO Auto-generated catch block  
  53.             e.printStackTrace();  
  54.         } catch (IOException e) {  
  55.             // TODO Auto-generated catch block  
  56.             e.printStackTrace();  
  57.         }  
  58.         filePost.releaseConnection();  
  59.         return fromAgentResult;  
  60.     }

  1. /**
   2.      * 发送文件到另一台服务器B
   3.      *  
   4.      * @param File file 附件
   5.      * @param serviceType服务类型
   6.      * @param spId id
   7.      * @return
   8.      */  
   9.     public String sendApply(File file, String serviceType, String spId) {  
  10.         String fromAgentResult = "";  
  11.         HttpClient client = new HttpClient();  
  12.         PostMethod filePost = new PostMethod(msUrl+"?serviceType="+serviceType+"&spId="+spId+"&type=menu");  
  13. //       MultipartPostMethod filePost = new MultipartPostMethod(msUrl);  
  14.         // 若上传的文件比较大 , 可在此设置最大的连接超时时间   
  15.          client.getHttpConnectionManager(). getParams().setConnectionTimeout(8000);    
  16.   
  17.         try {  
  18.   
  19.             FilePart fp = new FilePart(file.getName(), file);  
  20.             MultipartRequestEntity mrp= new MultipartRequestEntity(new Part[]{fp}, filePost.getParams());  
  21.             filePost.setRequestEntity(mrp);  
  22.   
  23.             //使用系统提供的默认的恢复策略  
  24.             filePost.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,  
  25.                 new DefaultHttpMethodRetryHandler());  
  26.   
  27.             int httpStat = client.executeMethod(filePost);  
  28.             System.out.println("httpStat----"+httpStat);  
  29.             if (!(httpStat == HttpStatus.SC_OK)) {  
  30.                 fromAgentResult = "connected fail:" + httpStat;  
  31.             } else if (httpStat == HttpStatus.SC_OK) {  
  32.                   
  33.                 try {  
  34.                     DocumentBuilderFactory factory = DocumentBuilderFactory  
  35.                             .newInstance();  
  36.                     DocumentBuilder builder = factory.newDocumentBuilder();  
  37.                     Document doc = builder  
  38.                             .parse(filePost.getResponseBodyAsStream());  
  39.                     doc.normalize();  
  40.                     // NodeList optypeNL= doc.getElementsByTagName("optype");  
  41.                     NodeList resultNL = doc.getElementsByTagName("result");  
  42.                     // fromAgentOptype=  
  43.                     // optypeNL.item(0).getFirstChild().getNodeValue();  
  44.                     fromAgentResult = resultNL.item(0).getFirstChild()  
  45.                             .getNodeValue();  
  46.                     System.out.println("发送请求完毕，接收状态："+fromAgentResult);  
  47.                 } catch (Exception e) {  
  48.                     e.printStackTrace();  
  49.                 }  
  50.             }  
  51.         } catch (HttpException e) {  
  52.             // TODO Auto-generated catch block  
  53.             e.printStackTrace();  
  54.         } catch (IOException e) {  
  55.             // TODO Auto-generated catch block  
  56.             e.printStackTrace();  
  57.         }  
  58.         filePost.releaseConnection();  
  59.         return fromAgentResult;  
  60.     }

B服务器接收：

Java代码

   1. boolean bl = false;  
   2.     System.out.println("接收文件开始--------------");  
   3.     String serviceType = request.getParameter("serviceType");  
   4.     String spId = request.getParameter("spId");  
   5.     String type = request.getParameter("type");  
   6.     if (type.equals("menu")) {  
   7.   
   8.         DiskFileUpload fu = new DiskFileUpload();  
   9.         fu.setSizeMax(1000000);  
  10.   
  11.         List fileItems;  
  12.   
  13.         try {  
  14.             fileItems = fu.parseRequest(request);  
  15.             Iterator itr = fileItems.iterator();  
  16.             while (itr.hasNext()) {  
  17.                 FileItem fi = (FileItem) itr.next();  
  18.   
  19.                 if (!fi.isFormField()) {  
  20.                     System.out.println("\nNAME: " + fi.getName());  
  21.                     System.out.println("SIZE: " + fi.getSize());  
  22.                     try {  
  23.                         String newFileName = msu.updateName(Integer  
  24.                                 .parseInt(serviceType), spId);  
  25.                         System.out.println("newFileName---------------"  
  26.                                 + newFileName);  
  27.                         File fNew = new File(applyFilePath, newFileName);  
  28.                         fi.write(fNew);  
  29.                         bl = msu.acceptApply(Integer.parseInt(serviceType),  
  30.                                 spId, newFileName);  
  31.   
  32.                         System.out.println(fNew.getAbsolutePath());  
  33.   
  34.                     } catch (Exception e) {  
  35.                         // TODO Auto-generated catch block  
  36.                         e.printStackTrace();  
  37.                     }  
  38.                 } else {  
  39.                     System.out.println("Field =" + fi.getFieldName());  
  40.                 }  
  41.             }  
  42.   
  43.         } catch (FileUploadException e1) {  
  44.             // TODO Auto-generated catch block  
  45.             e1.printStackTrace();  
  46.         }  
  47.     }

boolean bl = false;
        System.out.println("接收文件开始--------------");
        String serviceType = request.getParameter("serviceType");
        String spId = request.getParameter("spId");
        String type = request.getParameter("type");
        if (type.equals("menu")) {

            DiskFileUpload fu = new DiskFileUpload();
            fu.setSizeMax(1000000);

            List fileItems;

            try {
                fileItems = fu.parseRequest(request);
                Iterator itr = fileItems.iterator();
                while (itr.hasNext()) {
                    FileItem fi = (FileItem) itr.next();

                    if (!fi.isFormField()) {
                        System.out.println("\nNAME: " + fi.getName());
                        System.out.println("SIZE: " + fi.getSize());
                        try {
                            String newFileName = msu.updateName(Integer
                                    .parseInt(serviceType), spId);
                            System.out.println("newFileName---------------"
                                    + newFileName);
                            File fNew = new File(applyFilePath, newFileName);
                            fi.write(fNew);
                            bl = msu.acceptApply(Integer.parseInt(serviceType),
                                    spId, newFileName);

                            System.out.println(fNew.getAbsolutePath());

                        } catch (Exception e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    } else {
                        System.out.println("Field =" + fi.getFieldName());
                    }
                }

            } catch (FileUploadException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
            }
        }

Java代码

1. //下面是返回执行结果

//下面是返回执行结果

Java代码

   1.   msu.responseToAS(response, bl);  
   2.   System.out.println("接收申请处理完毕，状态：" + bl);  
   3.   return null;  

  msu.responseToAS(response, bl);
  System.out.println("接收申请处理完毕，状态：" + bl);
  return null;

Java代码

1. //msu.responseToAS

//msu.responseToAS

Java代码

public void responseToAS(HttpServletResponse response, boolean synSuccess) {  
2.   try {  
3.    PrintWriter out = response.getWriter();  
4.    if (synSuccess)  
5.     out  
6.       .println("<?xml version=\"1.0\" encoding=\"UTF-8\"?><root><result>ok</result></root>");  
7.    else  
8.     out  
9.       .println("<?xml version=\"1.0\" encoding=\"UTF-8\"?><root><result>fail</result></root>");  
10.   } catch (IOException e) {  
11.    e.printStackTrace();  
12.    System.out.println("responseToAS--error");  
13.   }  
14.  }

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2010-12-10 17:43
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