title: JScrollPane doesn't work
body: <p>My JScrollPane is around JTextArea:</p>
  
  <pre><code>    ...
      errorText = new JTextArea();
      errorText.setLineWrap(true);
      errorText.setWrapStyleWord(true);
      errorText.setPreferredSize(new Dimension(300, 150));
  
      JScrollPane scrollPane = new JScrollPane(errorText);
      scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
      scrollPane.setBorder(BorderFactory.createTitledBorder("Info Area"));
      ...
  </code></pre>
  
  <p>and code, that adds text to errorText:</p>
  
  <pre><code>public void setText(String mes) {
      e140TEST2.errorText.append(lineNum + ".   " + mes + "\n");
      lineNum++;
  }
  </code></pre>
  
  <p>after adding some num of lines (when text have more height, than JTextArea), JScrollPane doesn't work (text isn't scrooling). What it can be??</p>