Java 8 Streams Java Java API
The static method, Collector#mapping() returns a Collector which maps each element of the stream to type U and collect the mapped type according to a provided downstream Collector.
<T,U,A,R> Collector<T,?,R> mapping(Function<? super T,? extends U> mapper,
Collector<? super U,A,R> downstream)
Parameters
mapper: This function transforms the input values of type T to type U.
downstream: This collector transforms the values of type U to final type R.
Examples
 package com.logicbig.example.collectors;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
public class MappingExample {
public static void main (String[] args) {
Stream<String> s = Stream.of("apple", "banana", "orange");
List<String> list = s.collect(Collectors.mapping(s1 -> s1.substring(0, 2),
Collectors.toList()));
System.out.println(list);
}
}
Output[ap, ba, or]
Original Post
|
