Java 8 – Filter a null value from a Stream

Review a Stream containing null values.

Java8Examples.java

package com.mycareerrepublic.java8;

import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class Java8Examples {

    public static void main(String[] args) {

        Stream<String> language = Stream.of("java", "python", "node", null, "ruby", null, "php");

        List<String> result = language.collect(Collectors.toList());

        result.forEach(System.out::println);

    }
}

output

java
python
node
null   // <--- NULL
ruby
null   // <--- NULL
php

Solution

To solve it, uses Stream.filter(x -> x!=null)

Java8Examples.java

package com.mycareerrepublic.java8;

import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class Java8Examples {

    public static void main(String[] args) {

        Stream<String> language = Stream.of("java", "python", "node", null, "ruby", null, "php");

        //List<String> result = language.collect(Collectors.toList());

        List<String> result = language.filter(x -> x!=null).collect(Collectors.toList());

        result.forEach(System.out::println);


    }
}

output

java
python
node
ruby
php

Alternatively, filter with Objects::nonNull

import java.util.List;

 List<String> result = language.filter(Objects::nonNull).collect(Collectors.toList());

SHARES

Share

Pin it

Tweet

Share

Share

Share

Buffer

Print

About Mariano

I'm Ethan Mariano a software engineer by profession and reader/writter by passion.I have good understanding and knowledge of AngularJS, Database, javascript, web development, digital marketing and exploring other technologies related to Software development.