Java tutorial
//package com.java2s; import java.util.Comparator; import java.util.Map; import java.util.SortedMap; import java.util.concurrent.ConcurrentSkipListMap; public class Main { public static <K, V> ConcurrentSkipListMap<K, V> createConcurrentSkipListMap() { return new ConcurrentSkipListMap<K, V>(); } public static <K, V> ConcurrentSkipListMap<K, V> createConcurrentSkipListMap(Comparator<? super K> comparator) { if (comparator == null) { return new ConcurrentSkipListMap<K, V>(); } return new ConcurrentSkipListMap<K, V>(comparator); } public static <K, V> ConcurrentSkipListMap<K, V> createConcurrentSkipListMap( Map<? extends K, ? extends V> map) { if (map == null) { return new ConcurrentSkipListMap<K, V>(); } return new ConcurrentSkipListMap<K, V>(map); } public static <K, V> ConcurrentSkipListMap<K, V> createConcurrentSkipListMap( SortedMap<? extends K, ? extends V> map) { if (map == null) { return new ConcurrentSkipListMap<K, V>(); } return new ConcurrentSkipListMap<K, V>(map); } }