swing - Java progress bar not progressing, though the file gets downloaded? -

i have visited this , , several other pages on forum , went through swing on oracle docs. of code doesn't work progressbar, if emulate codes line line , few adjustment in code. don't know why not working! feeling pity on myself can't make work.

1. i know there issue edt, but, on myself can't figure out. think code working on worker threads updating progress bar.

2. also, once when code downloads, again if reset fields , selected items, subsequent calls download blocked. file created,but not downloaded. size remains 0. please explain why?

i created swingworker instance , called updation of fileprogressbar doinbackground() method, , calling done(). but, didn't work. file gets downloaded successfully, but, progress bar doesn't move inch!!!

public class client{   public static void main(string[] args) {     swingutilities.invokelater(new runnable() {         @override         public void run() {             new makegui().setvisible(true);         }     });             }  }  class makegui extends jframe implements propertychangelistener{ private jtextfield clientnametf; private jlabel displaylabel; private jbutton downloadbutton; private jbutton exitbutton; private jcombobox filecombobox; private jprogressbar fileprogressbar; private jbutton filestatusbutton; private jlabel finallabel; private jtextfield statustextfield; private jlabel titlelabel; private jbutton resetbutton; private jlabel loginlabel; private progressworker pw; private static jframe jf; public static string ip_address_to_connect;  public makegui() {     filecombobox = new javax.swing.jcombobox();     displaylabel = new javax.swing.jlabel();     filestatusbutton = new javax.swing.jbutton();     statustextfield = new javax.swing.jtextfield();     downloadbutton = new javax.swing.jbutton();     fileprogressbar = new javax.swing.jprogressbar();     exitbutton = new javax.swing.jbutton();     finallabel = new javax.swing.jlabel();     titlelabel = new javax.swing.jlabel();     loginlabel = new javax.swing.jlabel();     clientnametf = new javax.swing.jtextfield();     resetbutton = new javax.swing.jbutton();     callpainting(); }  public void callpainting(){     setlocationrelativeto(null);     setbounds(300, 0, 300, 300);     filecombobox.setmodel(new javax.swing.defaultcomboboxmodel(new string[] { "algorithm- hacker.mkv", "arun_asad.docx", "johnny sins.jpg", "mgh.java.the.complete.reference.9th.edition.pdf", "rabbit4.11-src.tar.gz", "samudra.jpg", "syngress - 7 deadliest web application attacks (2010) (attica).pdf", "tu hai ki nahi (roy).mp3" }));      finallabel.setlabelfor(finallabel);      titlelabel.settext("distributed file downloading system");      loginlabel.settext("your login name");      displaylabel.settext("select item wanna download");      filestatusbutton.settext("check status of file");     filestatusbutton.addactionlistener(new java.awt.event.actionlistener() {         @override         public void actionperformed(java.awt.event.actionevent evt) {             filestatusbuttonactionperformed(evt);         }     });      downloadbutton.settext("start download");     downloadbutton.setenabled(false);     downloadbutton.addactionlistener(new java.awt.event.actionlistener() {         @override         public void actionperformed(java.awt.event.actionevent evt) {             downloadbuttonactionperformed(evt);         }     });      fileprogressbar.setborder(javax.swing.borderfactory.creatematteborder(1, 1, 1, 1, new java.awt.color(187, 55, 55)));     fileprogressbar.setstringpainted(true);     fileprogressbar.setminimum(0);     fileprogressbar.setmaximum(100);     fileprogressbar.setvalue(0);     //fileprogressbar.setindeterminate(false);      resetbutton.settext("reset");     resetbutton.addactionlistener(new java.awt.event.actionlistener() {         @override         public void actionperformed(java.awt.event.actionevent evt) {             resetbuttonactionperformed(evt);         }     });      exitbutton.settext("exit application");     exitbutton.addactionlistener(new java.awt.event.actionlistener() {         @override         public void actionperformed(java.awt.event.actionevent evt) {             exitbuttonactionperformed(evt);         }     });     pack(); }  public void filestatusbuttonactionperformed(java.awt.event.actionevent evt) {                                                      try {         string clientname=clientnametf.gettext();         int choiceoffile = filecombobox.getselectedindex();         new server().requestfile(choiceoffile,clientname);         ip_address_to_connect=new server().returnipaddress();         statustextfield.settext("server available = "+ip_address_to_connect);         if(!(statustextfield.gettext().isempty()))             downloadbutton.setenabled(true);         else             downloadbutton.setenabled(false);     } catch (ioexception ex) {         finallabel.settext(ex.getmessage());     } }  public void downloadbuttonactionperformed(java.awt.event.actionevent evt)  {     downloadbutton.setenabled(false);     boolean completion=false;        long fsize=new server().returnfilesize();     string filesize;     long initialtime = 0l;     if(fsize <= 0) {         filesize = "0";     }     final string[] units = new string[] { "b", "kb", "mb", "gb", "tb" };     int digitgroups = (int) (math.log10(fsize)/math.log10(1024));     filesize= new decimalformat("#,##0.#").format(fsize/math.pow(1024, digitgroups)) + " " + units[digitgroups];                    string choiceoffile = (string)filecombobox.getselecteditem();     int dialogbutton=joptionpane.yes_no_option;     if(new file(choiceoffile).exists()){         int dialogresult=joptionpane.showconfirmdialog(null,"would delete already"                 + " existing file(press yes delete or no quit)???","confirm action", dialogbutton);         if(dialogresult==joptionpane.yes_option){             new file(choiceoffile).delete();         }         else {             finallabel.settext("file exists!!! if wish, can download file...");             system.exit(-1);         }     }    finallabel.settext("file size downloaded = "+filesize);       progressworker pw = new progressworker(choiceoffile,ip_address_to_connect,fsize);    initialtime = system.nanotime();    pw.addpropertychangelistener(this);                    /*else if (name.equals("state")) {                             swingworker.statevalue state = (swingworker.statevalue)evt.getnewvalue();                             switch (state) {                                 case done :                              {                                 downloadbutton.setenabled(true);                                     break;                             }                                     }                         }*/    pw.execute();             try {                 initialtime = pw.get();             } catch (interruptedexception | executionexception ex) {                 ex.printstacktrace();             }     long finaltime=system.nanotime();      float difference = (float)((finaltime-initialtime)/1000000000.0);     statustextfield.settext("time difference = "+difference);     }  public void resetbuttonactionperformed(java.awt.event.actionevent evt) {                                                     clientnametf.settext("");         statustextfield.settext("");         finallabel.settext("");         filecombobox.setselectedindex(0);         fileprogressbar.setvalue(0); }   public void exitbuttonactionperformed(java.awt.event.actionevent evt) {                                                    int response = joptionpane.showconfirmdialog(null, "are sure want exit application?", "confirm",         joptionpane.yes_no_option, joptionpane.warning_message);         if (response == joptionpane.no_option) {         system.out.println("no button clicked");         } else if (response == joptionpane.yes_option) {             system.exit(0);         } else if (response == joptionpane.closed_option) {          system.out.println("joptionpane closed");         }         }   @override public void propertychange(propertychangeevent evt) {    if("progress" == evt.getpropertyname()){        int progress = (integer)evt.getnewvalue();        fileprogressbar.setvalue(progress);    } }  class progressworker extends swingworker<long,integer>{ string cof,ip; long filesize; long initialtime; file downloadingfile;  public progressworker(string choiceoffile,string ip_address_to_connect,long fsize) {     this.cof = choiceoffile;     this.ip = ip_address_to_connect;     this.filesize = fsize;     downloadingfile = new file("/home/you/desktop/bash/client",cof); }  @override public long doinbackground() throws exception {     int temp=1;     boolean flag=true;     int progresspercent = 0;     setprogress(progresspercent);     initialtime=system.nanotime();     if(swingutilities.iseventdispatchthread()==true)         system.out.println("true edt.");     else         system.out.println("worker threads...");     startfileclient.startdownloading(cof,ip);          while(progresspercent<100 && downloadingfile.length() != filesize){         //system.out.println("length = "+downloadingfile.length());         progresspercent = (int)((downloadingfile.length()*100.0)/filesize);         setprogress(progresspercent);         thread.sleep(50);     }     return initialtime; }  @override public void done(){     toolkit.getdefaulttoolkit().beep();     downloadbutton.setenabled(true);     finallabel.settext("downloading done..."); }  }  }