package java.util;
public interface SortedMap<K, V> extends Map<K, V> {
//排序使用的Comparator比较器
Comparator<? super K> comparator();
//返回一个视图,范围是左闭右开区间[fromkey,tokey)
SortedMap<K, V> subMap(K fromKey, K toKey);
//返回视图,[最小key,tokey)
SortedMap<K, V> headMap(K toKey);
//返回视图,[fromkey,最大key]
SortedMap<K, V> tailMap(K fromKey);
//返回最小key
K firstKey();
//返回最大key
K lastKey();
//返回视图集合************************************************************//
//Returns a {@link Set} view of the keys contained in this map.
Set<K> keySet();
//Returns a {@link Collection} view of the values contained in this map.
Collection<V> values();
//Returns a {@link Set} view of the mappings contained in this map.
Set<Map.Entry<K, V>> entrySet();
}