Filter Null Values in Java: Discussing 3 Options

Discussing 3 examples of filtering null values from Collections

Originally Published in https://asyncq.com/

Introduction

• It's common to receive a collection where null values are included.
• The input collection that we received can contain null values in it.

1, 2, 3, 4, null, null

• It's not safe to operate on this ArrayList, we might get a null pointer exception.
• In this short article, Let’s quickly discuss what are the possible ways to filter null values from the ArrayList.

Option 1

• In this option, we create an additional result ArrayList, then iterate over the input array using for loop and compare for null on each element in the array.

        List<Integer> integers = Arrays.asList(1, 2, 3, 4, null, null);

        List<Integer> result = new ArrayList<>();
        for(Integer val: integers){
            if(val==null) continue;
            result.add(val);
        }
        System.out.println("===> "+Arrays.toString(result.toArray()));

===> [1, 2, 3, 4]

Option 2

• Another option is to convert the list to streams API to get all the benefits of…