| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.function.BiFunction; |
| |
| public class MapMerge { |
| public static void main(String[] args) { |
| Map<String, String> map = new HashMap<>(); |
| map.put("k", "v"); |
| // :: error: (return) |
| map.merge("k", "v", (a, b) -> null).toString(); |
| } |
| |
| void foo(Map<String, String> map) { |
| // :: error: (return) |
| merge(map, "k", "v", (a, b) -> null).toString(); |
| } |
| |
| <K, V> V merge( |
| Map<K, V> map, |
| K key, |
| V value, |
| BiFunction<? super V, ? super V, ? extends V> remappingFunction) { |
| return value; |
| } |
| } |