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   // <--- NULL
ruby
null   // <--- NULL
php

Solution

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

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

1. Objects::nonNull JavaDoc
2. Java 8 Streams filter examples
3. Java 8 Collectors JavaDoc