public static void setEditorVisibleSize(Editor editor, int widthInChars, int heightInChars) {
   Dimension size =
       new Dimension(
           widthInChars * EditorUtil.getSpaceWidth(Font.PLAIN, editor),
           heightInChars * editor.getLineHeight());
   ((EditorEx) editor).getScrollPane().getViewport().setExtentSize(size);
 }