Java implementation FTP upload download

The code is as follows

<span style= "FONT-SIZE:18PX;" >import Java.io.BufferedOutputStream; Import Java.io.File; Import Java.io.FileInputStream; Import Java.io.FileOutputStream; Import Java.io.FileWriter; Import java.io.IOException; Import Java.io.InputStream; Import Java.util.Arrays; Import java.util.List; Import org.apache.commons.net.ftp.FTPClient; Import Org.apache.commons.net.ftp.FTPClientConfig; Import Org.apache.commons.net.ftp.FTPFile; Import Org.apache.commons.net.ftp.FTPListParseEngine; Import org.apache.commons.net.ftp.FTPReply; Import org.dom4j.Document; Import Org.dom4j.DocumentHelper; Import org.dom4j.Element; Import Org.dom4j.io.OutputFormat; Import Org.dom4j.io.XMLWriter; public class Ftphelper {private ftpclient FTP = NULL;/** * FTP server */private String server;/** * User name */private STR ing uname; /** * Password * */private String password; /** * Connection port, default */private int port = 21; Private document document; Public Ftphelper (string server, int port, string uname, string password) {This. Server = server; if (This.port > 0) {this.port = port;} this.uname = uname; This.password = password; Initialize FTP = new ftpclient (); /** * Connect FTP Server * * @param server * @param uname * @param password * @return * @throws Exception */Public FTPCL Ient Connectftpserver () throws Exception {try {ftp.configure (Getftpclientconfig ()); Ftp.connect (This.server, This.port); if (!ftp.login (This.uname, This.password)) {ftp.logout (); ftp = NULL; return FTP;}//file type, default is ASCII Ftp.setfiletype (FTPC Lient. Binary_file_type); Ftp.setcontrolencoding ("GBK"); Set the passive mode Ftp.enterlocalpassivemode (); Ftp.setconnecttimeout (2000); Ftp.setbuffersize (1024); Response information int replycode = Ftp.getreplycode (); if ((! Ftpreply.ispositivecompletion (Replycode)) {//Close FTP connection closeftpclient ();//free space FTP = NULL; throw new Exception ("Login FTP Service The device fails, please check! [Server: "+ server +", "+" User: "+ uname +", "+" Password: "+ Password);} else {return FTP;}} catch (Exception e) {ftp.disconnect (); ftp = null; throw e;}}/** * Configure FTP connection Parameters * * @return * @throws Exception */public Ftpclientconfig Getftpclientconfig () throws Exception {St Ring Systemkey = ftpclientconfig.syst_nt; String Serverlanguagecode = "zh"; Ftpclientconfig conf = new Ftpclientconfig (Systemkey); Conf.setserverlanguagecode (Serverlanguagecode); Conf.setdefaultdateformatstr ("Yyyy-mm-dd"); return conf; /** * Upload files to the FTP root directory * * @param localfile * @param newName * New file name * @throws Exception */Public Boolean UploadFile (String localfile, String newName) throws Exception {InputStream input = null; Boolean success = false; try {F ile file = null; if (Checkfileexist (LocalFile)) {file = new file (localfile);} input = new FileInputStream (file); Success = Ftp.storefile (newName, input); if (!success) {throw new Exception ("File upload failed!");}} catch (Exception e) {throw e;} finally {if (input! = null) {Input.close ();}} return success; /** * Upload file to FTP root * * @param input * @param newName * New file name * @throws ExCeption */Public Boolean uploadfile (inputstream input, String newName) throws Exception {Boolean success = false; try { Success = Ftp.storefile (newName, input); if (!success) {throw new Exception ("File upload failed!");}} catch (Exception e) {throw e;} finally {if (input! = null) {Input.close ();}} return success; }/** * Specify path to FTP upload file * * @param localfile * @param newName * New file name * @param remotefoldpath * @throws EXC Eption */Public Boolean UploadFile (string localfile, String newName, String remotefoldpath) throws Exception {Inputstre AM input = null; Boolean success = false; try {File File = null, if (Checkfileexist (LocalFile)) {file = new file (localfile);} input = new FileInputStream (file); Change the current path to the specified path if (!this.changedirectory (Remotefoldpath)) {System.out.println ("Server path does not exist!"); return false;} success = FTP . StoreFile (newName, input); if (!success) {throw new Exception ("File upload failed!");}} catch (Exception e) {throw e;} finally {if (input! = null) {Input.close (); }} return success; }/** * Specify path to FTP upload file * * @param input * @param newName * New file name * @param remotefoldpath * @throws Excepti On */Public Boolean uploadfile (InputStream input, String newName, String remotefoldpath) throws Exception {Boolean succ ESS = false;  try {//Change the current path to the specified path if (!this.changedirectory (Remotefoldpath)) {System.out.println ("Server path does not exist!"); return false;} success = Ftp.storefile (newName, input); if (!success) {throw new Exception ("File upload failed!");}} catch (Exception e) {throw e;} finally {if (input! = null) {Input.close ();}} return success;  /** * Download file from FTP server * * @param remotepath * FTP path (without file name) * @param filename * Download filename * @param  LocalPath * Local Path */public Boolean DownloadFile (string RemotePath, String fileName, String localPath) throws Exception {Bufferedoutputstream output = null; Boolean success = false; try {//Check local path this.checkfileexist (LocalPath); Change the working Path if (!this.changedirectory (RemotePath)) {System.out.println ("Server path does not exist"); return false;}//Lists the list of files under the current working path list<ftpfile> fileList = This.getfilelist (); if (fileList = = NULL | | filelist.size () = = 0) {System.out.println ("The file does not exist under the current path of the server! "); return success; } for (Ftpfile ftpfile:filelist) {if (Ftpfile.getname (). Equals (FileName)) {File Localfilepath = new File (LocalPath + F Ile.separator + ftpfile.getname ()); Output = new Bufferedoutputstream (new FileOutputStream (Localfilepath)); Success = Ftp.retrievefile (Ftpfile.getname (), output); }} if (!success) {throw new Exception ("File download failed!");}} catch (Exception e) {throw e;} finally {if (output! = null) {Output.close ();}} return success; /** * Get file Stream from FTP server * * @param remotefilepath * @return * @throws Exception */Public InputStream downloadFile (Str ing Remotefilepath) throws Exception {return Ftp.retrievefilestream (Remotefilepath);}/** * Get a list of files under the specified path on the FTP server * @param filePath * @return */public list<ftpfile> getftpserverfilelist (String RemotEpath) throws Exception {Ftplistparseengine engine = ftp.initiatelistparsing (RemotePath); list<ftpfile> ftpfiles = Arrays.aslist (Engine.getnext (25)); return ftpfiles; /** * Gets the list of files under [specified path] on the FTP server * * @param path * @return * @throws Exception */public list<ftpfile> Getfileli St (String RemotePath) throws Exception {list<ftpfile> ftpfiles = arrays.aslist (Ftp.listfiles (RemotePath)); return ftpfiles; /** * Get the file list under FTP server [current working path] * * @param path * @return * @throws Exception */public list<ftpfile> Getfilel IST () throws Exception {list<ftpfile> ftpfiles = arrays.aslist (Ftp.listfiles ()); return ftpfiles;}/** * Change FTP server Work Path * * @param remotefoldpath */Public Boolean changedirectory (String remotefoldpath) throws Exception {return FTP . Changeworkingdirectory (Remotefoldpath); }/** * Delete file * * @param remotefilepath * @return * @throws Exception */Public Boolean deleteftpserverfile (String R Emotefilepath) throws Exception {return FTP. DeleteFile (Remotefilepath); }/** * Create directory * * @param remotefoldpath * @return * */public Boolean createfold (String remotefoldpath) throws Exceptio  n {Boolean flag = Ftp.makedirectory (Remotefoldpath), if (!flag) {throw new Exception ("Failed to create Directory");} return false;}/** *  Delete directory * @param remotefoldpath * @return * @throws Exception */public boolean deletefold (String Remotefoldpath) throws Exception {return ftp.removedirectory (Remotefoldpath);}/** * Delete directories and files * * @param remotefoldpath * @return */PU Blic boolean deletefoldandsubfiles (String remotefoldpath) throws Exception {Boolean success = false; list<ftpfile> list = This.getfilelist (Remotefoldpath); if (list = = NULL | | list.size () = = 0) {return deletefold (Remotefoldpath);} for (Ftpfile ftpfile:list) {String name = Ftpfile.getname (); if (Ftpfile.isdirectory ()) {success = Deletefoldandsubfiles (Remotefoldpath + "/" + name); if (!success) break;} else {s uccess = Deleteftpserverfile (Remotefoldpath + "/" + name); if (!success) break; }} if (!success) return false; Success = Deletefold (Remotefoldpath); return success; /** * Check if local path exists * * @param filePath * @return * @throws Exception */public boolean checkfileexist (String Filepa Th) throws Exception {Boolean flag = false; File File = new file (FilePath); if (!file.exists ()) {throw new Exception ("The local path does not exist, please check!");} else {flag = true;} return flag; }/** * Create XML file * @return */public Element getcurrentelement () {document = Documenthelper.createdocument (); return doc Ument.addelement ("root"); /** * Generate directory XML file */public void Createdirectoryxml (String remotepath,element fatherelement) throws exception{list<f tpfile> list = This.getfilelist (); for (Ftpfile ftpfile:list) {Element currentelement = fatherelement;//current directory node String newremotepath = remotepath+ Ftpfile.getname (); if (Ftpfile.isdirectory ()) {Element direlement = fatherelement.addelement ("dir"); Direlement.addattribute ("Name", Ftpfile.getname ()); Currentelement = Direlement This.changedirectory (Newremotepath); Start Createdirectoryxml (newremotepath,direlement) from the root directory; }else{Element fileelement = fatherelement.addelement ("file");//File Node Fileelement.settext (Ftpfile.getname ());}}         }/** * Save XML */public void SaveXML () {XMLWriter output = new XMLWriter ();         Output formatted OutputFormat format = Outputformat.createprettyprint ();             try {output = new XMLWriter (New FileWriter ("Src/com/shine/ftp/config/dir.xml"), format);             Output.write (this.document);         Output.close ();         } catch (IOException e) {e.printstacktrace ();  }}/** * Close FTP connection * * @param FTP * @throws Exception */public void Closeftpclient (ftpclient ftp) throws Exception {  try {if (ftp.isconnected ()) ftp.logout (); Ftp.disconnect ();} catch (Exception e) {throw new Exception ("Error closing FTP service!");} /** * Close FTP connection * * @throws Exception */public void closeftpclient () throws Exception {this.closeftpclient (this.ft p); } /** * Get Attribute Method * */Public ftpclient getftp () {return FTP,} public String Getserver () {return server;} pub Lic string Getuname () {return uname;} public String GetPassword () {return password,} public int getport () {return por T }/** * Set Attribute Method * */public void Setftp (ftpclient ftp) {this.ftp = FTP;} public void Setserver (String s  erver) {this.server = server;} public void Setuname (string uname) {this.uname = uname;} public void SetPassword (string Password) {this.password = password;} public void Setport (int port) {this.port = port;}/** * Main method (TEST) * * Problem: Upload life  The new file name cannot have Chinese, otherwise the upload fails. * * @param args */public static void main (string[] args) {try {ftphelper fu = new Ftphelper ("192.168.2.18", +, "adm Inistrator "," Sunshine "); Fu.connectftpserver (); Element fatherelement = Fu.getcurrentelement (); Fu.createdirectoryxml ("/", fatherelement); Fu.savexml (); } catch (Exception e) {System.out.println ("Exception information:" + e.getmessage ());}} }</span>

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Java implementation FTP upload download