Servlet实现文件上传的三种方法总结
Servlet实现文件上传的三种方法总结
1.通过getInputStream()取得上传文件。
/**
*Tochangethistemplate,chooseTools|Templates
*andopenthetemplateintheeditor.
*/
packagenet.individuals.web.servlet;
importjava.io.DataInputStream;
importjava.io.FileOutputStream;
importjava.io.IOException;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
/**
*
*@authorBarudisshu
*/
@WebServlet(name="UploadServlet",urlPatterns={"/UploadServlet"})
publicclassUploadServletextendsHttpServlet{
/**
*ProcessesrequestsforbothHTTP
*GETand
*POSTmethods.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
protectedvoidprocessRequest(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
response.setContentType("text/html;charset=UTF-8");
//读取请求Body
byte[]body=readBody(request);
//取得所有Body内容的字符串表示
StringtextBody=newString(body,"ISO-8859-1");
//取得上传的文件名称
StringfileName=getFileName(textBody);
//取得文件开始与结束位置
Positionp=getFilePosition(request,textBody);
//输出至文件
writeTo(fileName,body,p);
}
//构造类
classPosition{
intbegin;
intend;
publicPosition(intbegin,intend){
this.begin=begin;
this.end=end;
}
}
privatebyte[]readBody(HttpServletRequestrequest)throwsIOException{
//获取请求文本字节长度
intformDataLength=request.getContentLength();
//取得ServletInputStream输入流对象
DataInputStreamdataStream=newDataInputStream(request.getInputStream());
bytebody[]=newbyte[formDataLength];
inttotalBytes=0;
while(totalBytes
/**
*HandlestheHTTP
*GETmethod.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
@Override
protectedvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
/**
*HandlestheHTTP
*POSTmethod.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
@Override
protectedvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
/**
*Returnsashortdescriptionoftheservlet.
*
*@returnaStringcontainingservletdescription
*/
@Override
publicStringgetServletInfo(){
return"Shortdescription";
}//
}
2.通过getPart()、getParts()取得上传文件。
body格式：
POSThttp://www.example.comHTTP/1.1
Content-Type:multipart/form-data;boundary=----WebKitFormBoundaryrGKCBY7qhFd3TrwA
------WebKitFormBoundaryrGKCBY7qhFd3TrwA
Content-Disposition:form-data;name="text"
title
------WebKitFormBoundaryrGKCBY7qhFd3TrwA
Content-Disposition:form-data;name="file";filename="chrome.png"
Content-Type:image/png
PNG...contentofchrome.png...
------WebKitFormBoundaryrGKCBY7qhFd3TrwA--
[html]viewplaincopy
/**
*Tochangethistemplate,chooseTools|Templates
*andopenthetemplateintheeditor.
*/
packagenet.individuals.web.servlet;
importjava.io.FileNotFoundException;
importjava.io.FileOutputStream;
importjava.io.IOException;
importjava.io.InputStream;
importjava.io.OutputStream;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.MultipartConfig;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
importjavax.servlet.http.Part;
/**
*
*@authorBarudisshu
*/
@MultipartConfig
@WebServlet(name="UploadServlet",urlPatterns={"/UploadServlet"})
publicclassUploadServletextendsHttpServlet{
/**
*ProcessesrequestsforbothHTTP
*GETand
*POSTmethods.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
protectedvoidprocessRequest(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
Partpart=request.getPart("photo");
StringfileName=getFileName(part);
writeTo(fileName,part);
}
//取得上传文件名
privateStringgetFileName(Partpart){
Stringheader=part.getHeader("Content-Disposition");
StringfileName=header.substring(header.indexOf("filename=\"")+10,header.lastIndexOf("\""));
returnfileName;
}
//存储文件
privatevoidwriteTo(StringfileName,Partpart)throwsIOException,FileNotFoundException{
InputStreamin=part.getInputStream();
OutputStreamout=newFileOutputStream("e:/workspace/"+fileName);
byte[]buffer=newbyte[1024];
intlength=-1;
while((length=in.read(buffer))!=-1){
out.write(buffer,0,length);
}
in.close();
out.close();
}
//
/**
*HandlestheHTTP
*GETmethod.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
@Override
protectedvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
/**
*HandlestheHTTP
*POSTmethod.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
@Override
protectedvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
/**
*Returnsashortdescriptionoftheservlet.
*
*@returnaStringcontainingservletdescription
*/
@Override
publicStringgetServletInfo(){
return"Shortdescription";
}
}
3、另一种较为简单的方法：采用part的wirte(StringfileName)上传，浏览器将产生临时TMP文件
/**
*Tochangethistemplate,chooseTools|Templates
*andopenthetemplateintheeditor.
*/
packagenet.individuals.web.servlet;
importjava.io.IOException;
importjava.io.PrintWriter;
importjavax.servlet.ServletException;
importjavax.servlet.annotation.MultipartConfig;
importjavax.servlet.annotation.WebServlet;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
importjavax.servlet.http.Part;
/**
*采用part的wirte(StringfileName)上传，浏览器将产生临时TMP文件。
*@authorBarudisshu
*/
@MultipartConfig(location="e:/workspace")
@WebServlet(name="UploadServlet",urlPatterns={"/UploadServlet"})
publicclassUploadServletextendsHttpServlet{
/**
*ProcessesrequestsforbothHTTP
*GETand
*POSTmethods.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
protectedvoidprocessRequest(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
//处理中文文件名
request.setCharacterEncoding("UTF-8");
Partpart=request.getPart("photo");
StringfileName=getFileName(part);
//将文件写入location指定的目录
part.write(fileName);
}
privateStringgetFileName(Partpart){
Stringheader=part.getHeader("Content-Disposition");
StringfileName=header.substring(header.indexOf("filename=\"")+10,header.lastIndexOf("\""));
returnfileName;
}
//
/**
*HandlestheHTTP
*GETmethod.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
@Override
protectedvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
/**
*HandlestheHTTP
*POSTmethod.
*
*@paramrequestservletrequest
*@paramresponseservletresponse
*@throwsServletExceptionifaservlet-specificerroroccurs
*@throwsIOExceptionifanI/Oerroroccurs
*/
@Override
protectedvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
processRequest(request,response);
}
/**
*Returnsashortdescriptionoftheservlet.
*
*@returnaStringcontainingservletdescription
*/
@Override
publicStringgetServletInfo(){
return"Shortdescription";
}//
}
以上就是Servlet实现文件上传的实例，如有疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！