You want to change it through code? If so, you can use the setValue method in either the table or the table's model. The difference between the two is that the table's column indexes can be different from the model's column indexes.
Also, please use Boolean.FALSE, Boolean.TRUE and/or Boolean.valueOf(boolean) instead of new Boolean. That will decrease the number of objects created; since there are only two boolean values, these constants will be all that is needed. valueOf will return one of these two.