FileUpload series: (2) File Upload example

Example

package com.rk.web.servlet;import java.io.bufferedreader;import java.io.file;import  java.io.fileinputstream;import java.io.ioexception;import java.io.inputstream;import  Java.io.inputstreamreader;import java.io.unsupportedencodingexception;import java.util.list;import  java.util.UUID;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet; Import javax.servlet.http.httpservletrequest;import javax.servlet.http.httpservletresponse;import  org.apache.commons.fileupload.fileitem;import org.apache.commons.fileupload.fileitemfactory;import  org.apache.commons.fileupload.FileUploadException;import  org.apache.commons.fileupload.disk.diskfileitemfactory;import  Org.apache.commons.fileupload.servlet.servletfileupload;import org.apache.commons.io.fileutils;public  class uploadservlet extends httpservlet {// upload directory, save uploaded resources Public void  doget (HttpSErvletrequest request, httpservletresponse response) throws servletexception,  ioexception {/********* File Upload component:  process file upload ************/try {// 1.  file upload factory fileitemfactory  factory = new diskfileitemfactory ();// 2.  Create File upload core tool class servletfileupload  Upload = new servletfileupload (Factory);//  One, sets the maximum size allowed for a single file:  30mupload.setfilesizemax (30*1024*1024);//  Second, set the total size of the file upload form:  80mupload.setsizemax (80*1024*1024);//  third,   set the Upload form file name encoding/ /  equivalent: request.setcharacterencoding ("UTF-8"), Upload.setheaderencoding ("UTF-8");// 3.  judgment:  Whether the current form is a file upload form if  (upload.ismultipartcontent (Request)) {// 4.  Convert the request data to a Fileitem object, and then use the collection package list< Fileitem> list = upload.parserequest (Request);//  traverse:  to get each uploaded data for  (FileItem  item: list) {//  judgment: Plain Text data if  (Item.isformfield ()) {//  Plain Text data string fieldname  = item.getfieldname ();  FORM element name String content = item.getstring ();//  the form element name,  corresponding data//item.getstring (" UTF-8 ");   Specify the encoding System.out.println (fieldname + " = " + content);}   Upload file (file stream)  ---->  upload data to else {//  file in upload directory string fieldname =  Item.getfieldname ();//  form element name String name = item.getname ();//  file name String content  = item.getstring ();//  form element name,  corresponding data string type = item.getcontenttype ();//   File Type Inputstream in = item.getinputstream (); //  upload file stream/* *   four, File name duplicate  *   for different users of the same name file, do not want to overwrite!  *   background Processing:  adds a unique tag to the user! */// a.  randomly generates a unique tag string id =  Uuid.randomuuid (). toString ();// b.  and filename stitching name = id + "#" + name;//  Gets the upload base path String path = getservletcontext (). Getrealpath ("/upload");//  Create destination file File file  = new&nbSp File (path,name);//  tool class, document upload Item.write (files); Item.delete ();    // Delete system-generated temporary files System.out.println ();}}} Else {system.out.println ("The current form is not a file upload form, processing failed!") ");}}  catch  (exception e)  {e.printstacktrace ();}}   Manual Implementation process private void upload (httpservletrequest request)  throws ioexception, Unsupportedencodingexception {/*request.getparameter ("");  // get/postrequest.getquerystring ();  //  get the data for the Get Commit  request.getinputstream (); //  get the data for the post submission    *//********* * * Manually get file Upload form data ************///1.  get form data stream Inputstream in =  request.getinputstream ();// 2.  Conversion Stream Inputstreamreader instream = new inputstreamreader (in,  "UTF-8");//3.  Buffered Stream Bufferedreader reader = new bufferedreader (instream);//  output Data string str =  null;while  ((Str = reader.readline ())  != null)  {system.out.println (str);}   Close Reader.close (); Instream.close (); In.close ();} Public void dopost (Httpservletrequest request, httpservletresponse response) throws  servletexception, ioexception {this.doget (Request, response);}}

FileUpload series: (2) File Upload example