File upload and download in Java Web development

First, with the STRUTS2 framework

1. Environment construction
1.1 Guide Pack: Conmmons-fileupload-1.2.1.jar Conmmons-io-1.4.jar and other framework jar packages

2. Page: Slightly
3. File Upload:
3.1 Designing a File Upload Tool class: Fileuploadutils

　　　　

1  Public classfileuploadutils{2                 3                 //the path to which the file is to be uploaded, configurable4 @Resource5                 PrivateString FilePath;6 7                 Privatestring Createnewfilepath (String fileName) {8 9                     //the original path is the configured filepathTenString basepath=FilePath; One                     //sub-path is formatted/year/month/day form ASimpleDateFormat sdf=NewSimpleDateFormat ("/yyyy/mm/dd"); -String Subpath=sdf.format (NewDate ()); -  the                     //If no directory folder is created -File dir=NewFile (basepath+subpath); -                     if(!dir.exists ()) { -                         //to create a directory folder recursively + dir.mkdirs (); -                     } +                      A                     //new file name is uuid+ file extension atString Newfilename=uuid.randomuuid (). ToString ()// -+filename.substring (Filename.lastindexof (".")); -                     //This is the newly generated file path -String newfilepath=basepath+subpath+NewFileName; -  -                     returnNewfilepath; in                 } -  to                  PublicString saveuploadfile (File uploadfile,string fileName) { +                     //New file path -String newfilepath=Createnewfilepath (filepath,filename); the                     Try{ *                         //get file input/output stream $InputStream in=NewFileInputStream (uploadfile);Panax NotoginsengOutputStream out=NewFileOutputStream (newfilepath); -                          the                         //write throttling to the destination path file +                         byte[] buff=New byte[1024]; A                         intLen=0; the                          while(Len=in.read (Buff))!=-1){ +Out.write (buff,0, Len); -                         } $  $  -}Catch(Exception e) { -                      the                         Throw Newruntimeexception (); -}finally{Wuyi                         Try{ the in.close (); -}Catch(Exception e) { Wu                             Throw Newruntimeexception (); -}finally{ About                             Try{ $ out.close (); -}Catch(Exception e) { -                                 Throw Newruntimeexception (); -                             } A                              +                         } the                          -                     } $                      the                     returnNewfilepath; the                 } the             } the             

4. File Download: Struts2 in the package is very simple

1  Public classXxxactionextendsActionsupportImplementsmodeldriven{2             3             //input stream to be used for smashing4             PrivateInputStream InputStream;5             //need to write setter,getter;6 7             //model-driven, simplified reference, replaces Strtus1 's Actionform8             PrivateXXX model=NewXXX ();9              PublicXXX Getmodel () {Ten Returm model; One             } A  -              PublicString Download () { -XXX xxx=Xxxservice.getbyid (Model.getid ()); theinputstream=NewFileInputStream (NewFile (Xxx.getpath ())); -                  -                 //solve Chinese garbled problem -String Filename=urlencoder.encode (Xxx.getfilename (), "Utf-8"); +ActionContext.getContext.put ("FileName", fileName); -             } +}

The rest is Struts.xml's configuration.

Ii. using pure servlet (cont.)

File upload and download in Java Web development