How to implement FTP functionality in a Java application (turn)

How the program implements FTP functionality in Java applications


Dalian Jie Tong Computer Technology Co., Ltd.


Wang Yu





----in Java programming, you may experience FTP programming, and this article demonstrates how to implement it.





----This procedure is developed by JBUILDER2.0, and in order to save space I will only list the main three parts. The Ftplist section is used to display files on the FTP server (with a slight figure). The Getbutton section is for sending a file from the FTP server. The Putbutton section uploads a file to the FTP server. Don't forget to introduce two library files (import Sun.net.*,import sun.net.ftp.*) in your program. The following are the Java source programs for these three sections.





----1) Displays the files on the FTP server





void ftplist_actionperformed (ActionEvent e) {


String Server=serveredit.gettext ();


//Input IP address of the FTP server


String User=useredit.gettext ();


//Login to the FTP server username


String Password=passwordedit.gettext ();


//Login to the FTP server username password


String Path=pathedit.gettext ();


//ftp The path on the server


try {


ftpclient ftpclient=new ftpclient ();


//Create FtpClient Object


ftpclient.openserver (server);


//Connection FTP server


ftpclient.login (user, password);


//Login to FTP server


if (path.length ()!=0) ftpclient.cd (path);


Telnetinputstream is=ftpclient.list ();


int C;


while ((C=is.read ())!=-1) {


System.out.print ((char) c);}


Is.close ();


ftpclient.closeserver ()//exit FTP server


} catch (IOException ex) {;}


  }














2) Send a file from the FTP server








void getbutton_actionperformed (ActionEvent e) {


String Server=serveredit.gettext ();


String User=useredit.gettext ();


String Password=passwordedit.gettext ();


String Path=pathedit.gettext ();


String Filename=filenameedit.gettext ();


try {


ftpclient ftpclient=new ftpclient ();


ftpclient.openserver (server);


ftpclient.login (user, password);


if (path.length ()!=0) ftpclient.cd (path);


Ftpclient.binary ();


telnetinputstream is=ftpclient.get (filename);


file File_out=new file (filename);


FileOutputStream os=new


FileOutputStream (file_out);


byte[] Bytes=new byte[1024];


int C;


while ((C=is.read (bytes))!=-1) {


Os.write (BYTES,0,C);


       }


Is.close ();


Os.close ();


Ftpclient.closeserver ();


} catch (IOException ex) {;}


  }








3) Upload a file to the FTP server





void putbutton_actionperformed (ActionEvent e) {


String Server=serveredit.gettext ();


String User=useredit.gettext ();


String Password=passwordedit.gettext ();


String Path=pathedit.gettext ();


String Filename=filenameedit.gettext ();


try {


ftpclient ftpclient=new ftpclient ();


ftpclient.openserver (server);


ftpclient.login (user, password);


if (path.length ()!=0) ftpclient.cd (path);


ftpclient.binary ();


telnetoutputstream os=ftpclient.put (filename);


file File_in=new file (filename);


fileinputstream is=new FileInputStream (file_in);


byte[] Bytes=new byte[1024];


int C;


while ((C=is.read (bytes))!=-1) {


Os.write (bytes,0,c);}


Is.close ();


Os.close ();


Ftpclient.closeserver ();


The catch (IOException ex) {;}


  }


}








----This program compiles and passes in the win95/98/nt,jbuilder2.0 environment.