Java FTP Point of the intermittent transmission of File upload and download _java

Based on the Apache FTP implementation file upload download tool, upload files need to consider the following issues (example is the continuation of the function):

(1) Whether there is a directory for the FTP server, if the directory does not exist, you need to create a directory.

(2), to determine whether the upload file already exists, if there is a need to delete before uploading or continued transmission.

1, upload or download the status of the enumeration class:

Package com.scengine.wtms.utils.ftp; 
 
Public enum Uploadstatus 
{ 
  file_exits (0), create_directory_success (1), Create_directory_fail (2), Upload_ From_break_success (3), Upload_from_break_faild (4), download_from_break_success (5), Download_from_break_faild (6), Upload_new_file_success (7), upload_new_file_failed (8), delete_remote_success (9), Delete_remote_faild (a), Remote_ Bigger_local (one), Remote_smaller_locall (a); 
 
  private int status; 
 
  public int GetStatus () 
  {return 
    status; 
  } 
 
  public void setstatus (int status) 
  { 
    this.status = status; 
  } 
 
  Uploadstatus (int status) 
  { 
    this.status = status; 
  } 
} 

2, Tool class code:

Package com.scengine.wtms.utils.ftp; 
Import Java.io.File; 
Import Java.io.FileInputStream; 
Import Java.io.FileOutputStream; 
Import java.io.IOException; 
Import Java.io.InputStream; 
Import Java.io.OutputStream; 
Import Java.io.PrintWriter; 
Import Org.apache.commons.net.PrintCommandListener; 
Import Org.apache.commons.net.ftp.FTP; 
Import org.apache.commons.net.ftp.FTPClient; 
Import Org.apache.commons.net.ftp.FTPFile; 
 
Import org.apache.commons.net.ftp.FTPReply; 
 
  public class Continueftp {private FtpClient ftpclient = new FtpClient (); The/** * Object construction setting outputs the commands used in the procedure to the console/public continueftp () {This.ftpClient.addProtocolCommandListener (new P) 
  Rintcommandlistener (New PrintWriter (System.out));  
   /** * * * * java Programming for connecting to FTP server * * @param hostname * Host name * * @param port * 
   * * @param username * User name * * @param password * Password * * * @return Whether the connection succeeded * * @throws IOEXCEPtion */public boolean connect (string hostname, int port, string Username, string password) throws IOException 
 
    {Ftpclient.connect (hostname, port); 
      if (Ftpreply.ispositivecompletion (Ftpclient.getreplycode ())) {if (Ftpclient.login (username, password)) 
      {return true; 
    } disconnect (); 
 
  return false;  
   /** * * Download files from FTP server * * @param remote file path * * @param local file path * * @return Success * * @throws ioexception * * @SuppressWarnings ("resource") public boolean Down 
 
    Load (string remote, String local) throws IOException {Ftpclient.enterlocalpassivemode (); 
 
    Ftpclient.setfiletype (Ftp.binary_file_type); 
 
    Boolean result; 
 
    File F = new file (local); 
 
    ftpfile[] files = ftpclient.listfiles (remote); 
      if (files.length!= 1) {System.out.println ("Remote file is not unique"); 
    return false; } Long lremotesize = Files[0].getsize (); 
      if (f.exists ()) {OutputStream out = new FileOutputStream (f, true); 
 
      SYSTEM.OUT.PRINTLN ("Local File size is:" + f.length ()); 
 
        if (F.length () >= lremotesize) {System.out.println ("Local file size is larger than remote file size, download aborted"); 
 
      return false; 
 
      } ftpclient.setrestartoffset (F.length ()); 
 
      result = Ftpclient.retrievefile (remote, out); 
 
    Out.close (); 
      else {outputstream out = new FileOutputStream (f); 
      result = Ftpclient.retrievefile (remote, out); 
    Out.close (); 
 
  return result;      /** * * * * Upload files to FTP server, support breakpoint Continuation * * @param local * name, absolute path * * @param remote * Remote file path, using/home/directory1/subdirectory/file.ext * According to the path specified on Linux, support multilevel directory nesting, support recursively create nonexistent directory structure * * @retur N Upload Results * * @throws IOException/@SuppressWarnings ("resource") public uploadstatus upload (String loca L, String Remote) throws IOException {//Set Passivemode transmission Ftpclient.enterlocalpassivemode (); 
 
    A binary stream is set to transmit Ftpclient.setfiletype (ftp.binary_file_type); 
 
    Uploadstatus result; 
 
    Processing of remote directories String remotefilename = remote; 
 
      if (Remote.contains ("/")) {remotefilename = remote.substring (Remote.lastindexof ("/") + 1); 
 
      String directory = remote.substring (0, Remote.lastindexof ("/") + 1); if (!directory.equalsignorecase ("/") &&!ftpclient.changeworkingdirectory (directory)) {//If the remote eye 
 
        Record does not exist, then recursively creates the remote server directory int start = 0; 
 
        int end = 0; 
 
        if (Directory.startswith ("/")) {start = 1; 
 
        else {start = 0; 
 
        End = Directory.indexof ("/", start); 
 
          while (true) {String subdirectory = remote.substring (start, end); if (!ftpclient.changeworkingdirectory (subdirEctory)) {if (Ftpclient.makedirectory (subdirectory)) {ftpclient. 
 
            Changeworkingdirectory (subdirectory); 
 
              else {System.out.println ("Create directory Failed"); 
 
            return uploadstatus.create_directory_fail; 
 
          } start = end + 1; 
 
          End = Directory.indexof ("/", start); 
 
          Check that all directories are created if (end <= start) {break; 
 
    Check whether there is a remote file ftpfile[] files = ftpclient.listfiles (remotefilename); 
 
      if (files.length = = 1) {Long remotesize = Files[0].getsize (); 
 
      File F = new file (local); 
 
      Long localsize = F.length (); 
 
      if (remotesize = = localsize) {return uploadstatus.file_exits; else if (Remotesize > Localsize) {return uploadstatus.remote_bigger_local;
 
      //Attempt to move the read pointer within the file to implement the breakpoint InputStream is = new FileInputStream (f); 
 
        if (Is.skip (remotesize) = = remotesize) {ftpclient.setrestartoffset (remotesize); 
 
        if (Ftpclient.storefile (remote, is)) {return uploadstatus.upload_from_break_success; 
 
        }//If the breakpoint is not successful, delete the file on the server and upload if (!ftpclient.deletefile (Remotefilename)) { 
 
      return uploadstatus.delete_remote_faild; 
 
      is = new FileInputStream (f); 
 
      if (Ftpclient.storefile (remote, is)} {result = Uploadstatus.upload_new_file_success; 
 
      else {result = uploadstatus.upload_new_file_failed; 
 
    } is.close (); 
 
      else {InputStream is = new FileInputStream (local); 
 
      if (Ftpclient.storefile (Remotefilename, is)} {result = Uploadstatus.upload_new_file_success; 
 
      } else {  result = uploadstatus.upload_new_file_failed; 
    } is.close (); 
 
  return result;  
  /** * * Disconnect from remote server * * @throws ioexception/public void disconnect () throws IOException 
    {if (ftpclient.isconnected ()) {ftpclient.disconnect (); 
    } public static void Main (string[] args) {continueftp myftp = new Continueftp (); 
 
      try {myftp.connect ("192.168.1.200", "Duser", "HTPDuserXP32"); System.out.println (Myftp.upload ("C:\\users\\administrator\\desktop\\swing.drawer.jar", "/jars/swing.drawer.jar") 
 
      )); 
 
    Myftp.disconnect (); 
 
    catch (IOException e) {System.out.println ("Connection FTP error:" + e.getmessage ());  } 
 
  } 
 
}

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