With whom did the Portuguese have to fight in the Indian Ocean for a trade monopoly?

With whom did the Portuguese have to fight in the Indian Ocean for a trade monopoly? The rulers of which countries entered into an alliance with the Portuguese and why?

Until the Portuguese, Arabs (in the west) and Malay Muslims (in the east) held control over the sea trade in the Indian Ocean. Fighting with them, the Portuguese entered into trade alliances with their opponents, the Hindu Rajas, with the Chinese and Japanese, who did not have a powerful ocean-going fleet.