Duhat refers to one of the fruits found and grown in the Philippines. It is called in English with various names , such as Java Plum , Black Plum , Jambolan, and  Indian Blackaberry. Its scientific name is Syzygium cumini and belongs to the Family Myrtaceae.

The fruit of the Duhat tree  is oval which is about 1 to 2 centimeters in length. It is dark purple to black in color, fleshy and one-seeded, with a sweet-astringent taste. Its flesh is eaten on hand when ripe. The Filipino people has a distinct way to eat Duhat, they put it in a bowl with rock salt , put on a tight cover, then shake the container until the fruit and the salt are mixed properly.

In the Philippines , Duhat is also called Lomboy, Longboi, etc.

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Duhat is the Filipino term for Java plum, a kind of fruit found in the Philippines. It is usually eaten by drizzling salt into the fruits and shake it from a container with a cover until its a bit soften and salt is fully mixed. 

In my opinion the Philippines Duhat is almost similar in taste as sour cherries.