Httpclient上传文件

akarta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：


PostMethodpost = 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 " ;


PostMethodpostMethod = new PostMethod(url);




StringPart sp = new StringPart( " TEXT " , " testValue " );


FilePart fp = new FilePart( " file " , " test.txt " , new File( " ./temp/test.txt " ));




MultipartRequestEntitymrp = 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PostMethodpostMethod = 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 " ;


PostMethodpostMethod = 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 " );


MultipartRequestEntitymrp = 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();


}

httpclient笔记（二）

不多说了，直接上示例：

A服务器：

msURL为：http://192.168.7.203:8080

Java代码

/**

* 发送文件到另一台服务器B

*

* @param File file 附件

* @param serviceType服务类型

* @param spId id

* @return

*/

public String sendApply(File file, String serviceType, String spId) {

String fromAgentResult = "" ;

HttpClient client = new HttpClient();

PostMethodfilePost = new PostMethod(msUrl+ "?serviceType=" +serviceType+"&spId=" +spId+ "&type=menu" );

// MultipartPostMethodfilePost = new MultipartPostMethod(msUrl);

// 若上传的文件比较大 , 可在此设置最大的连接超时时间

client.getHttpConnectionManager(). getParams().setConnectionTimeout(8000);

try {

FilePart fp = new FilePart(file.getName(), file);

MultipartRequestEntitymrp= new MultipartRequestEntity( new Part[]{fp}, filePost.getParams());

filePost.setRequestEntity(mrp);

//使用系统提供的默认的恢复策略

filePost.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,

new DefaultHttpMethodRetryHandler());

int httpStat = client.executeMethod(filePost);

System.out.println("httpStat----" +httpStat);

if (!(httpStat == HttpStatus.SC_OK)) {

fromAgentResult = "connected fail:" + httpStat;

} else if (httpStat == HttpStatus.SC_OK) {

try {

DocumentBuilderFactory factory = DocumentBuilderFactory

.newInstance();

DocumentBuilder builder = factory.newDocumentBuilder();

Document doc = builder

.parse(filePost.getResponseBodyAsStream());

doc.normalize();

// NodeList optypeNL= doc.getElementsByTagName("optype");

NodeList resultNL = doc.getElementsByTagName("result" );

// fromAgentOptype=

// optypeNL.item(0).getFirstChild().getNodeValue();

fromAgentResult = resultNL.item(0 ).getFirstChild()

.getNodeValue();

System.out.println("发送请求完毕，接收状态：" +fromAgentResult);

} catch (Exception e) {

e.printStackTrace();

}

}

} catch (HttpException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

filePost.releaseConnection();

return fromAgentResult;

}

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/**

* 发送文件到另一台服务器B

*

* @param File file 附件

* @param serviceType服务类型

* @param spId id

* @return

*/

public String sendApply(File file, String serviceType, String spId) {

String fromAgentResult = "";

HttpClient client = new HttpClient();

PostMethodfilePost = new PostMethod(msUrl+"?serviceType="+serviceType+"&spId="+spId+"&type=menu");

// MultipartPostMethodfilePost = new MultipartPostMethod(msUrl);

// 若上传的文件比较大 , 可在此设置最大的连接超时时间

client.getHttpConnectionManager(). getParams().setConnectionTimeout(8000);

try {

FilePart fp = new FilePart(file.getName(), file);

MultipartRequestEntitymrp= new MultipartRequestEntity(new Part[]{fp}, filePost.getParams());

filePost.setRequestEntity(mrp);

//使用系统提供的默认的恢复策略

filePost.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,

new DefaultHttpMethodRetryHandler());

int httpStat = client.executeMethod(filePost);

System.out.println("httpStat----"+httpStat);

if (!(httpStat == HttpStatus.SC_OK)) {

fromAgentResult = "connected fail:" + httpStat;

} else if (httpStat == HttpStatus.SC_OK) {

try {

DocumentBuilderFactory factory = DocumentBuilderFactory

.newInstance();

DocumentBuilder builder = factory.newDocumentBuilder();

Document doc = builder

.parse(filePost.getResponseBodyAsStream());

doc.normalize();

// NodeList optypeNL= doc.getElementsByTagName("optype");

NodeList resultNL = doc.getElementsByTagName("result");

// fromAgentOptype=

// optypeNL.item(0).getFirstChild().getNodeValue();

fromAgentResult = resultNL.item(0).getFirstChild()

.getNodeValue();

System.out.println("发送请求完毕，接收状态："+fromAgentResult);

} catch (Exception e) {

e.printStackTrace();

}

}

} catch (HttpException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

filePost.releaseConnection();

return fromAgentResult;

}

B服务器接收：

Java代码

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();

}

}

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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

//下面是返回执行结果

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//下面是返回执行结果

Java代码

msu.responseToAS(response, bl);

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

return null ;

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msu.responseToAS(response, bl);

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

return null;

Java代码

//msu.responseToAS

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//msu.responseToAS

Java代码

public void responseToAS(HttpServletResponse response, boolean synSuccess) {

try {

PrintWriter out = response.getWriter();

if (synSuccess)

out

.println("<?xml version=/"1.0/" encoding=/"UTF-8/"?><root><result>ok</result></root>" );

else

out

.println("<?xml version=/"1.0/" encoding=/"UTF-8/"?><root><result>fail</result></root>" );

} catch (IOException e) {

e.printStackTrace();

System.out.println("responseToAS--error" );

}

}