Class CollectionUtil


  • public final class CollectionUtil
    extends Object
    Utility class for working with collections and arrays.
    • Method Detail

      • asList

        public static <E> List<E> asList​(E... elements)
        Converts varargs to a List.
      • asSet

        public static <E> LinkedHashSet<E> asSet​(E... elements)
        Converts varargs to a Set.
      • asMap

        public static <K,​V> LinkedHashMap<K,​V> asMap​(Object... elements)
        Converts varargs to a Map where the elements are key/value pairs.
      • clone

        public static <K,​V> ConcurrentHashMap<K,​V> clone​(ConcurrentHashMap<K,​V> map)
        Clones a given ConcurrentHashMap by creating a new map and copying all entries from the original map. If the value of an entry is a Set or an ArrayList, a deep copy of the value is created. Otherwise, the value is copied as is.
      • addFirst

        public static <T> T[] addFirst​(T[] array,
                                       T element,
                                       Class<T> clazz)
        Adds the element argument to the start of the supplied array argument, but if the array is null then return the element as a new array with just that item in it.