Remove null elements from a List in Java

1). Removing all null elements in the List using while loop

The Java Collections Framework provides different ways to remove the null elements from the list.


<Integer> list = Lists.newArrayList(11,22,null, 33, null);
    while (list.remove(null));

or We can have


  <Integer> list = Lists.newArrayList(151,122,11,22,null, 33, null);
    list.removeAll(Collections.singleton(null));

2). Using Apache Commons Collections

The Apache Commons Collections library has CollectionUtils class contains filter method,which removes null from the given list. 


   List<Integer> list = Lists.newArrayList(151,122,11,22,null, 33, null);
    CollectionUtils.filter(list, PredicateUtils.notNullPredicate());

3). Using Lambdas from Java 8

The lambdas in java has filtering mechanism usong which we can remove null from list.

 
  List<Integer> list = Lists.newArrayList(151,122,11,22,null, 33, null);
    List<Integer> listWithoutNulls = list.parallelStream()
      .filter(Objects::nonNull)
      .collect(Collectors.toList());

In this article, we have seen Remove null elements from a List in Java.