import java.util.Objects;

import java.util.stream.Collectors;

​

// Call on objects themeselves

list.stream().filter(Objects::nonNull).collect(Collectors.toList());

// or

list.stream().filter(item -> item != null).collect(Collectors.toList());

​

// Call on memeber fields

list.stream().filter(item -> item.getId() != null)

  .collect(Collectors.toList());