several times change label text by click button in swing not work
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I need to change jlabel.text several times by one click button in swing. In this code i need set label text to start before dowork()  function and set it to end after dowork() (status type in jlabel and dowork has long time execution): 



     private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { 
            status.setText("start");
            try {
                Thread.sleep(10000);
            } catch (InterruptedException ex) {
                Logger.getLogger(PelakInRFID.class.getName()).log(Level.SEVERE, null, ex);
            }
            dowork();
            status.setText("end");
    
     }


In this code status only set to end and start doesn't show. 