private ConstPool compact0() {
        ConstPool cp = new ConstPool(thisclassname);
        thisClass = cp.getThisClassInfo();
        String sc = getSuperclass();
        if (sc != null)
            superClass = cp.addClassInfo(getSuperclass());

        if (interfaces != null) {
            int n = interfaces.length;
            for (int i = 0; i < n; ++i)
                interfaces[i]
                    = cp.addClassInfo(constPool.getClassInfo(interfaces[i]));
        }

        return cp;
    }