Files
2014-04-11 17:06:06 +02:00

27 lines
598 B
Java

import java.util.*;
import static java.util.stream.Collectors.groupingBy;
import static java.util.stream.Collectors.mapping;
import static java.util.stream.Collectors.toList;
class Test {
private static void run() {
List<R> list = Arrays.asList(new R());
System.out.println(
list.stream()
.collect(groupingBy(r -> r.get(String.class), mapping(r -> r.get(String.class),toList())
))
);
}
static class R {
<T> T get(Class<T> clazz) {
if (clazz == String.class)
return (T) "string";
throw new IllegalArgumentException();
}
}
}