if (child.getSubstring().equals("")) return;
    public void addInlineChild(Context c, InlineBox ib) {        if (ib == null) throw new NullPointerException("trying to add null child");        if (getChildCount() == 0 && ib instanceof InlineTextBox) {//first box on line            InlineTextBox child = (InlineTextBox) ib;            if (child.getSubstring().startsWith(WhitespaceStripper.SPACE)) {                String whitespace = c.getCurrentStyle().getStringProperty(CSSName.WHITE_SPACE);                if (whitespace.equals("normal") ||                        whitespace.equals("nowrap") ||                        whitespace.equals("pre-line"))                    child.setSubstring(child.start_index + 1, child.end_index);            }            if (child.getSubstring().equals("")) return;        }        ib.setParent(this);        addChild(ib);        if (ib.isChildrenExceedBounds()) {            setChildrenExceedBounds(true);        }    }