Returns false if any of the values ​​on the map is an empty string or just spaces in java8

Question

I am trying to write a one-line code that will return false if any of the values ​​on the map are an empty string or a string of spaces. Thoughts?

Something like an extended version:

 Optional.ofNullable(map).filter(s -> s.isEmpty());

Answer 1

using your current approach:

boolean present = 
        Optional.ofNullable(map)
                .filter(x -> 
                        x.values().stream()
                                  .noneMatch(s -> s != null && s.trim().isEmpty()))
                                  .isPresent();

or simply:

boolean present = map != null && 
                  map.values()
                     .stream()
                     .noneMatch(s -> s != null && s.trim().isEmpty());

Answer 2

What about:

return map.values().stream().noneMatch(v -> v != null && v.trim().isEmpty());

---

v.trim().isEmpty()true if the string is empty ( "") or contains only spaces.

noneMatchtrue if no elements in the stream (values ​​here) satisfy the predicate. This is a short circuit, so it is good and effective.

Answer 3

,

public static boolean containsNoEmptyString(Map<?,?> map) {
    return !map.containsValue("");
}

,

public static boolean containsNoBlankString(Map<?,String> map) {
    return map.values().stream().noneMatch(Pattern.compile("^\\s*$").asPredicate());
}

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