I have code that redirects system output to a jtext area, but that jtextarea doesnt update until the code is finished running. How do I modify the code to make the jtextarea update in real time during runtime?

private void updateTextArea(final String text) {
        SwingUtilities.invokeLater(new Runnable() {
          public void run() {
            consoleTextAreaInner.append(text);
          }
        });
      }
private void redirectSystemStreams() {
      OutputStream out = new OutputStream() {
        @Override
        public void write(int b) throws IOException {
          updateTextArea(String.valueOf((char) b));
        }

        @Override
        public void write(byte[] b, int off, int len) throws IOException {
          updateTextArea(new String(b, off, len));
        }

        @Override
        public void write(byte[] b) throws IOException {
          write(b, 0, b.length);
        }
      };

      System.setOut(new PrintStream(out, true));
      System.setErr(new PrintStream(out, true));
    }    

The rest of the code is mainly just an actionlistener for a button:

private void updateButtonActionPerformed(java.awt.event.ActionEvent evt) {                                             
    // TODO add your handling code here:
    String shopRoot = this.shopRootDirTxtField.getText();
    String updZipPath = this.updateZipTextField.getText();
    this.mainUpdater = new ShopUpdater(new File(shopRoot), updZipPath);
    this.mainUpdater.update();
}

That update() method begins the process of copying+pasting files on the file system and during that process uses system.out.println to provide an up-to-date status on where the program is currently at in reference to how many more files it has to copy.