/** Get the selection if there's any or get the identifier around
    * the position if there's no selection.
    * @param c component to work with
    * @param offset position in document - usually the caret.getDot()
    * @return the block (starting and ending position) enclosing the identifier
    *   or null if no identifier was found
    */
    public static int[] getSelectionOrIdentifierBlock(JTextComponent c, int offset)
    throws BadLocationException {
        BaseDocument doc = (BaseDocument)c.getDocument();
        Caret caret = c.getCaret();
        int[] ret;
        if (caret.isSelectionVisible()) {
            ret = new int[] { c.getSelectionStart(), c.getSelectionEnd() }; 
        } else if !(doc instanceof BaseDocument){
            ret = getIdentifierBlock(c, offset);
        }
        else {
            ret = getIdentifierBlock((BaseDocument)doc, caret.getDot());
        }

        return ret;
    }


  /** Get the word around the given position .
    * @param c component to work with
    * @param offset position in document - usually the caret.getDot()
    * @return the word.
    */
    public static String getWord(JTextComponent c, int offset) 
    throws BadLocationException {
	int[] blk = getIdentifierBlock(c, offset);
	Document doc = c.getDocument();
        return (blk != null) ? doc.getText(blk[0], blk[1] - blk[0]) : null;

    }

  /** Get the identifier around the given position or null if there's no identifier
    * around the given position. The identifier is not verified against SyntaxSupport.isIdentifier().
    * @param c JTextComponent to work on
    * @param offset position in document - usually the caret.getDot()
    * @return the block (starting and ending position) enclosing the identifier
    * or null if no identifier was found
    */
    public static int[] getIdentifierBlock(JTextComponent c, int offset)
    throws BadLocationException {
        String id = null;
	int[] ret = null;
	Document doc = c.getDocument();
        int idStart = javax.swing.text.Utilities.getWordStart(c, offset);
        if (idStart >= 0) {
            int idEnd = javax.swing.text.Utilities.getWordEnd(c, idStart);
            if (idEnd >= 0) {
                id = doc.getText(idStart, idEnd - idStart);
		ret = new int[] { idStart, idEnd };
		String trim = id.trim();
                if (trim.length() == 0 || (trim.length() == 1 && !Character.isJavaIdentifierPart(trim.charAt(0)))) {
		    int prevWordStart = javax.swing.text.Utilities.getPreviousWord(c, offset);
		    if (offset == javax.swing.text.Utilities.getWordEnd(c,prevWordStart )){
			ret = new int[] { prevWordStart, offset };
		    }
		}
		else if ((id != null) && (id.length() != 0)  && (id.indexOf(".") != -1)){
		    int index = offset - idStart;
		    int begin = id.substring(0, index).lastIndexOf(".");
		    begin = (begin == -1) ? 0 : begin + 1; //first index after the dot, if exists
		    int end = id.indexOf(".", index);
		    end = (end == -1) ? id.length() : end;
		    ret = new int[] { idStart+begin, idStart+end };
		}
            }
        }
        return ret;
    }