Java 8 - filter empty string from List not working

Since java 11 there is a new method Predicate::not.

So you can write it like that:

list.stream().filter(Predicate.not(String::isEmpty)).collect(Collectors.toList())

I suspect you are not keeping the result. The result is returned, the original list is not altered as this is functional programming style.

list = list.stream().filter(item-> !item.trim().isEmpty()).collect(Collectors.toList());

filter() keeps the elements that match the predicate. Soyou need the inverse predicate:

list.stream().filter(item-> !item.isEmpty()).collect(Collectors.toList());

This will also not modify the original list. It will create a filtered copy of the original list. So you need

list = list.stream().filter(item-> !item.isEmpty()).collect(Collectors.toList());

If you want to modify the original list, you should use

list.removeIf(item -> item.isEmpty());

or simply

list.removeIf(String::isEmpty);

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