#vulnerable code 
                                private void internalIndexedAdd(int index, T element) {
        nest.cat(JOhmUtils.getId(owner)).cat(field.getName()).lset(index,
                JOhmUtils.getId(element).toString());
        indexValue(element);
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private void internalIndexedAdd(int index, T element) {
        if (element != null) {
            nest.cat(JOhmUtils.getId(owner)).cat(field.getName()).lset(index,
                    JOhmUtils.getId(element).toString());
            indexValue(element);
        }
    }