swing - java catch process time real time progress bar -

new scanner(new url("some_url.txt").openstream(), "utf-8").usedelimiter("\\a").next(); 

using ^ data .txt-file save in string.

for progress bar, wondered if possible jobs (or in general methods etc.) count (or sth. that) time needed finished. can show in real time process time in bar.

is somehow possible?

edit:

package app.gui;      import java.awt.borderlayout;     import java.awt.eventqueue;     import java.net.url;     import java.util.scanner;      import javax.swing.jframe;     import javax.swing.jpanel;     import javax.swing.jprogressbar;     import javax.swing.uimanager;     import javax.swing.unsupportedlookandfeelexception;      import org.apache.commons.io.ioutils;      public class updater {          private jframe frame;         private static string rawg;         private static string versi;          public static void main(string[] args) {             eventqueue.invokelater(new runnable() {                 public void run() {                     try {                         rawg = new scanner(new url("some_url.txt").openstream(), "utf-8").usedelimiter("\\a").next();                         versi = ioutils.tostring(getclass().getclassloader().getresourceasstream("version.txt"));                     } catch (exception e) {                         system.out.println("error class updater try/catch raw github");                     }                     if (integer.parseint(rawg.split("\\.")[0]) < integer.parseint(versi.split("\\.")[0])) {                         system.out.println("version check failure, update needed");                         try {                             updater window = new updater();                             window.frame.setvisible(true);                         } catch (exception e) {                             system.out.println("error class updater try/catch initialize frame");                         }                                        } else {                         system.out.println("version check correct, no update needed");                     }                 }             });         }          public updater() {             initialize();         }          private void initialize() {             try {                 uimanager.setlookandfeel(uimanager.getsystemlookandfeelclassname());             } catch (classnotfoundexception | instantiationexception | illegalaccessexception                     | unsupportedlookandfeelexception e) {                 // todo auto-generated catch block                 e.printstacktrace();             }             frame = new jframe();             frame.setbounds(100, 100, 450, 300);             frame.setdefaultcloseoperation(jframe.exit_on_close);              jpanel panel = new jpanel();             frame.getcontentpane().add(panel, borderlayout.south);             panel.setlayout(new borderlayout(0, 0));              jprogressbar progressbar = new jprogressbar();             progressbar.setstringpainted(true);             panel.add(progressbar, borderlayout.north);         }      } 

is possible? yes. possible when using scanner.next() read contents of url? no.

you need read bytes yourself, , count them:

url url = new url("some_url.txt"); urlconnection conn = url.openconnection();  bytebuffer buffer = bytebuffer.allocate(conn.getcontentlength()); eventqueue.invokelater(() -> progressbar.setmaximum(buffer.limit())); eventqueue.invokelater(() -> progressbar.setvalue(0)); try (readablebytechannel channel = channels.newchannel(conn.getinputstream())) {     while (channel.read(buffer) >= 0) {         eventqueue.invokelater(() -> progressbar.setvalue(buffer.position()));     } }  buffer.flip(); string rawg = standardcharsets.utf_8.decode(buffer).tostring();