I have an ArrayList<Integer>. I want to check if all elements of the list are greater then or less then certain condition. I can do it by iterating on each element. But I want to know if there is any method in Collection class to get the answer like we can do to find maximum or minimum with Collections.max() and Collections.min() respectively.
4 Answers
If you have java 8, use stream's allMatch function (reference):
ArrayList<Integer> col = ...; col.stream().allMatch(i -> i>0); //for example all integers bigger than zero 
5 Comments
Kartik_Koro
Didn't know about this, seems useful! :D
Chirag
very useful..something new to me..Thanks
Chirag
I am not getting how to use this predicate and pass it in to argument. Can anyone give me demo ?
Stanislav Codes
Still useful and saves lives four years later :D
stackbacker
Should probably be noted that the above solution will return true for an empty list.
You can use Google guavas Iterables.all
Iterables.all(collection, new Predicate() { boolean apply(T element) { .... //check your condition } } 
Comments
You cannot check values without iterating on all elements of the list.
for(Integer value : myArrayList){ if(value > MY_MIN_VALUE){ // do my job } } I hope this will help
1 Comment
Chirag
I want to do my job only if all elements of list > of my condition
The answer col.stream().allMatch is the best solution for the original task, i.e. to check if all elements fulfill some condition.
If you instead want to find the min or max int value of a Stream/Collection you must first convert it to an IntStream using col.stream().mapToInt(ToIntFunction) where the ToIntFunction can be MyObject::getIntvalue or o -> o.getIntValue() or Integer::intValue if you already have a List<Integer> as explained on How do I get an IntStream from a List<Integer>?
maxandminmake no sense per se, becauseCollectionis a generic type. for instance if you haveCollection<Object>, what would bemaxandmin? take a look here: stackoverflow.com/questions/122105/…