How to add elements of a Java8 stream into an existing List
Javadoc of Collector shows how to collect elements of a stream into a new List. Is there an one-liner that adds the results … Read more
collectors
Java8: HashMap to HashMap using Stream / Map-Reduce / Collector
I know how to “transform” a simple Java List from Y -> Z, i.e.: List<String> x; List<Integer> y = x.stream() .map(s -> Integer.parseInt(s)) … Read more
NullPointerException in Collectors.toMap with null entry values
Collectors.toMap throws a NullPointerException if one of the values is null. I don’t understand this behaviour, maps can contain null pointers as value … Read more