Is the water in Japanese restaurants boiled or warm?

There is no warm water or hot water to eat in Japanese restaurants, only cold water and iced cold water. Because Japanese people are used to drinking cold water, regardless of adults, children and the elderly. Even in winter. When you enter the restaurant, the first thing I give you is a glass of cold water. But some Japanese restaurants will pour a cup of hot tea. If you are not used to it, you can ask the clerk for a cup of hot water.