void rediff() {
   try {
     if (myTopMessageDiffPanel != null) {
       myPanel.removeTopComponent(myTopMessageDiffPanel);
     }
     LineBlocks blocks = myData.updateEditors();
     setLineBlocks(blocks != null ? blocks : LineBlocks.EMPTY);
     if (blocks != null && blocks.getCount() == 0) {
       if (myData.isContentsEqual()) {
         setFileContentsAreIdentical();
       }
     }
   } catch (FilesTooBigForDiffException e) {
     setTooBigFileErrorContents();
   }
 }