Java 8 – Filter a null value from a Stream

Review a Stream containing null values.

package com.mkyong.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   // 
Solution
To solve it, uses Stream.filter(x -> x!=null)
Java8Examples.java

package com.mkyong.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());



References

Objects::nonNull JavaDoc
Java 8 Streams filter examples
Java 8 Collectors JavaDoc


		


			

				
filter  java8  null  stream