File Upload is divided into two parts:
(1) server: Use fileupload + common. Io to upload files;
(2) client: the HTTP Request Header for simulating File Upload;
Fileservlet. Java
Package Org. xiazdong. servlet; import Java. io. file; import Java. io. ioexception; import Java. util. list; import javax. servlet. servletexception; import javax. servlet. annotation. webservlet; 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. disk. diskf Ileitemfactory; import Org. apache. commons. fileupload. servlet. servletfileupload; @ webservlet ("/fileservlet") public class fileservlet extends httpservlet {protected void doget (httpservletrequest request, response) throws handle, ioexception {} protected void dopost (httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {diskfileitemf Actory factory = new diskfileitemfactory (); servletfileupload upload = new servletfileupload (factory); upload. setfilesizemax (1024*1024); // set the maximum size of the uploaded file. Try {list <fileitem> items = upload. parserequest (request); // get all the data in the form for (fileitem item: Items) {If (! Item. isformfield () {// If the uploaded file is string name = "d :\\" + item. getname (). substring (item. getname (). lastindexof ('\') + 1); string filename = Name; system. out. println (filename); file F = new file (filename); // save it to disk D. write (f); system. out. println ("uploaded successfully") ;}} catch (exception e) {e. printstacktrace ();}}}
Browser code:
<! Doctype HTML public "-// W3C // dtd html 4.01 transitional // en" "http://www.w3.org/TR/html4/loose.dtd"> <HTML> 2. Client preparation and core code1. Preparations
Because the client needs to simulate an HTTP request, we can first look at the HTTP request for file upload:
| Post/Server/fileservlet HTTP/1.1 Accept :*/* Referer: http: // localhost: 8080/Server/2.html Accept-language: ZH-CN User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; wow64; Trident/4.0; slcc2 ;. net CLR 2.0.50727 ;. net CLR 3.5.30729 ;. net CLR 3.0.30729; Media Center PC 6.0 ;. net4.0e ;. net4.0c; infopath.3) Content-Type: multipart/form-data; boundary = --------------------------- 7dc372520758 // The separator is used to separate multiple files and parameters. Accept-encoding: gzip, deflate HOST: localhost: 8080 Content-Length: 14610 Connection: keep-alive Cache-control: No-Cache ----------------------------- 7dc372520758 |
From this we can see that this HTTP request is difficult to simulate. Here we encapsulate a helper class, which is implemented by Teacher Li fuming. We can use it directly:
Httprequestutil. uploadfile (string path, Map <string, string> Params, formfile file)
Path: URL
Params: Common Parameters
File: File
Httprequestutil. uploadfiles (string path, Map <string, string> Params, formfile [] files)
Path: URL
Params: Common Parameters
Files: multiple files
Formfile. Java
Package COM. xiazdong. netword. HTTP. util; import Java. io. file; import Java. io. fileinputstream; import Java. io. filenotfoundexception; import Java. io. inputstream;/*** Upload File */public class formfile {/* Upload File data */private byte [] data; private inputstream instream; private file; /* file name */private string filname;/* request parameter name */private string parametername;/* content type */private string contenttype = "application/octet- Stream "; /*** this function is used to transmit the control parameter name * @ Param filname * @ Param data * @ Param parametername HTML of a small file * @ Param contenttype */Public formfile (string filname, byte [] data, string parametername, string contenttype) {This. data = data; this. filname = filname; this. parametername = parametername; If (contenttype! = NULL) This. contenttype = contenttype;}/*** this function is used to transmit large files * @ Param filname * @ Param file * @ Param parametername * @ Param contenttype */Public formfile (string filname, file file, string parametername, string contenttype) {This. filname = filname; this. parametername = parametername; this. file = file; try {This. instream = new fileinputstream (File);} catch (filenotfoundexception e) {e. printstacktrace ();} If (C Ontenttype! = NULL) This. contenttype = contenttype;} public file GetFile () {return file;} public inputstream getinstream () {return instream;} public byte [] getdata () {return data ;} public String getfilname () {return filname;} public void setfilname (string filname) {This. filname = filname;} Public String getparametername () {return parametername;} public void setparametername (string parametername) {This. parametername = parametername;} Public String getcontenttype () {return contenttype;} public void setcontenttype (string contenttype) {This. contenttype = contenttype ;}}
Httprequestutil. Java
Package COM. xiazdong. netword. HTTP. util; import Java. io. bufferedreader; import Java. io. bytearrayoutputstream; import Java. io. inputstream; import Java. io. inputstreamreader; import Java. io. outputstream; import java.net. httpurlconnection; import java.net. inetaddress; import java.net. socket; import java.net. URL; import java.net. urlconnection; import java.net. urlencoder; import Java. util. hashmap; import Java. util. map; Import Java. util. map. entry; import Java. util. set;/** this class is used to send HTTP requests. **/public class httprequestutil {/*** submits data directly to the server through the HTTP protocol. The following form submission function is implemented: * <form method = post action = "http: // 192.168.0.200: 8080/ssi/fileload/test. do "enctype =" multipart/form-Data "> <input type =" text "name =" name "> <input type =" text "name =" ID "> <Input type = "file" name = "imagefile"/> <input type = "file" name = "Zip"/> </form> * @ Param path PATH (Note: Avoid using a path test like localhost or 127.0.0.1 because it will point to the phone simulator and you can use a path test like http://www.itcast.cn or http: // 192.168.1.10: 8080) * @ Param Params the request parameter key is the parameter name, and the value is the parameter value * @ Param File Upload File */public static Boolean uploadfiles (string path, Map <string, string> Params, formfile [] files) throws exception {final string boundary = "--------------------------- 7da1_7580612"; // data separation line final string endline = "--" + boundary + "-- \ r \ N "; // data end sign int filedatalength = 0; If (files! = NULL & files. length! = 0) {for (formfile uploadfile: Files) {// obtain the total length of the file type data stringbuilder fileexplain = new stringbuilder (); fileexplain. append ("--"); fileexplain. append (Boundary); fileexplain. append ("\ r \ n"); fileexplain. append ("content-Disposition: Form-data; name = \" "+ uploadfile. getparametername () + "\"; filename = \ "" + uploadfile. getfilname () + "\" \ r \ n "); fileexplain. append ("Content-Type:" + uploadfile. getcontenttype () + "\ r \ N \ r \ n "); fileexplain. append (" \ r \ n "); filedatalength + = fileexplain. Length (); If (uploadfile. getinstream ()! = NULL) {filedatalength + = uploadfile. getFile (). length ();} else {filedatalength + = uploadfile. getdata (). length ;}} stringbuilder textentity = new stringbuilder (); If (Params! = NULL &&! Params. isempty () {for (map. entry <string, string> entry: Params. entryset () {// construct the object data textentity of the text type parameter. append ("--"); textentity. append (Boundary); textentity. append ("\ r \ n"); textentity. append ("content-Disposition: Form-data; name = \" "+ entry. getkey () + "\" \ r \ n "); textentity. append (entry. getvalue (); textentity. append ("\ r \ n") ;}// calculates the total length of the object data transmitted to the server. Int datalength = textentity. tostring (). getbyte S (). Length + filedatalength + endline. getbytes (). length; Url url = new URL (PATH); int Port = URL. getport () =-1? 80: URL. getport (); Socket socket = new socket (inetaddress. getbyname (URL. gethost (), Port); outputstream outstream = socket. getoutputstream (); // The string requestmethod = "Post" + URL sent in the HTTP request header is completed below. getpath () + "HTTP/1.1 \ r \ n"; outstream. write (requestmethod. getbytes (); string accept = "accept: image/GIF, image/JPEG, image/pjpeg, image/pjpeg, application/X-Shockwave-flash, application/XAML + XML, applica Tion/vnd. MS-xpsdocument, application/X-MS-xbap, application/X-MS-application, application/vnd. MS-Excel, application/vnd. MS-PowerPoint, application/MSWord, */* \ r \ n "; outstream. write (accept. getbytes (); string Language = "Accept-language: ZH-CN \ r \ n"; outstream. write (language. getbytes (); string contenttype = "Content-Type: multipart/form-data; boundary =" + boundary + "\ r \ n"; outstream. write (contenttyp E. getbytes (); string contentlength = "Content-Length:" + datalength + "\ r \ n"; outstream. write (contentlength. getbytes (); string alive = "connection: keep-alive \ r \ n"; outstream. write (alive. getbytes (); string host = "Host:" + URL. gethost () + ":" + port + "\ r \ n"; outstream. write (host. getbytes (); // After writing the HTTP Request Header, write another carriage return outstream Based on the HTTP protocol. write ("\ r \ n ". getbytes (); // send object data of all text types out of outstream. write (texten Tity. tostring (). getbytes (); // send object data of all file types if (files! = NULL & files. length! = 0) {for (formfile uploadfile: Files) {stringbuilder fileentity = new stringbuilder (); fileentity. append ("--"); fileentity. append (Boundary); fileentity. append ("\ r \ n"); fileentity. append ("content-Disposition: Form-data; name = \" "+ uploadfile. getparametername () + "\"; filename = \ "" + uploadfile. getfilname () + "\" \ r \ n "); fileentity. append ("Content-Type:" + uploadfile. getcontenttype () + "\ r \ n"); outstream. W Rite (fileentity. tostring (). getbytes (); If (uploadfile. getinstream ()! = NULL) {byte [] buffer = new byte [1024]; int Len = 0; while (LEN = uploadfile. getinstream (). read (buffer, 0, 1024 ))! =-1) {outstream. write (buffer, 0, Len);} uploadfile. getinstream (). close ();} else {outstream. write (uploadfile. getdata (), 0, uploadfile. getdata (). length);} outstream. write ("\ r \ n ". getbytes () ;}}// the end mark of the sent data, indicating that the data has ended outstream. write (endline. getbytes (); bufferedreader reader = new bufferedreader (New inputstreamreader (socket. getinputstream (); If (reader. readline (). indexof ("200") =-1) {// read the number returned by the Web Server Judge whether the request code is 200. If it is not 200, return false if the request fails;} outstream. flush (); outstream. close (); reader. close (); socket. close (); Return true;}/*** submit data to the server * @ Param path upload path (Note: Do not test using a path like localhost or 127.0.0.1, because it will point to the phone simulator, you can test using a path like http://www.itcast.cn or http: // 192.168.1.10: 8080) * @ Param Params request parameter key for Parameter Name, value is the parameter value * @ Param file */public static Boolean uploadfile (string path, Map <string, string> Params, Formfile file) throws exception {return uploadfiles (path, Params, new formfile [] {file });} /*** convert the input stream into a byte array * @ Param instream * @ return * @ throws exception */public static byte [] read2byte (inputstream instream) throws exception {bytearrayoutputstream outsteam = new bytearrayoutputstream (); byte [] buffer = new byte [1024]; int Len = 0; while (LEN = instream. read (buffer ))! =-1) {outsteam. write (buffer, 0, Len);} outsteam. close (); instream. close (); Return outsteam. tobytearray ();}/*** convert the input stream into a string * @ Param instream * @ return * @ throws exception */public static string read2string (inputstream instream) throws exception {bytearrayoutputstream outsteam = new bytearrayoutputstream (); byte [] buffer = new byte [1024]; int Len = 0; while (LEN = instream. read (buffer ))! =-1) {outsteam. write (buffer, 0, Len);} outsteam. close (); instream. close (); return new string (outsteam. tobytearray (), "UTF-8 ");}}
2. Core code
Formfile = new formfile (file. getname (), file, "document", "text/plain"); // "document" indicates the control name, and "text/plain" indicates the mimetypeboolean issuccess = httprequestutil of the file. uploadfile ("http: // 192.168.0.103: 8080/Server/fileservlet", null, formfile );
Iii. client code
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/><uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/><uses-permission android:name="android.permission.INTERNET"/>
Mainactivity. Java
Package Org. xiazdong. network. fileupload; import Java. io. file; import android. app. activity; import android. OS. bundle; import android. OS. environment; import android. view. view; import android. view. view. onclicklistener; import android. widget. button; import android. widget. edittext; import android. widget. toast; import COM. xiazdong. netword. HTTP. util. formfile; import COM. xiazdong. netword. HTTP. util. httprequestutil; public class mainactivity extends activity {private edittext filename; private button; private onclicklistener listener = new onclicklistener () {@ overridepublic void onclick (view v) {string fname = filename. gettext (). tostring (); If (environment. getexternalstoragestate (). equals (environment. media_mounted) | environment. getexternalstoragestate (). equals (environment. media_mounted_read_only) {file = new file (environment. getexternalstoragedirectory (), fname); // obtain the sdcard file if (file. exists () {formfile = new formfile (file. getname (), file, "document", "text/plain"); try {Boolean issuccess = httprequestutil. uploadfile ("http: // 192.168.0.103: 8080/Server/fileservlet", null, formfile); If (issuccess) {toast. maketext (mainactivity. this, "the file is uploaded successfully", toast. length_short ). show ();} else {toast. maketext (mainactivity. this, "File Upload Failed", toast. length_short ). show () ;}} catch (exception e) {e. printstacktrace () ;}} else {toast. maketext (mainactivity. this, "file does not exist", toast. length_short ). show () ;}} else {toast. maketext (mainactivity. this, "sdcard does not exist", toast. length_short ). show () ;}};@ override public void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); setcontentview (R. layout. main); filename = (edittext) This. findviewbyid (R. id. filename); button = (button) This. findviewbyid (R. id. button); button. setonclicklistener (listener );}}
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