Why was James II considered a constitutional monarchy?

James II was a king (a person who inherited power through heredity) who was constrained by the laws of Parliament and the Magna Carta. This makes him a constitutional monarch. This is in contrast to an absolute monarch, who is a king who has no constraints on his power, and a constitutional president, who is a person who is voted into power by the population and has constraints on his power from other branches of government and historical political documents.