Why does allMatch return true in case of empty list in Java?

Question

List<String> strings = new ArrayList<>();
boolean doAllMatch = strings.stream().allMatch(str -> str.startsWith("a"));

How funny is this. It is an empty list. Still it says all match. Is this what we as developer really want ??

Answer 1

Yes, generally. That's how pretty much every definition of all in any language works -- it's true that all the elements match the condition. There is no element that doesn't match the condition, after all.