Package org.apache.solr.common.util

Class CollectionUtil

  • public final class CollectionUtil
extends Object
    Methods for creating collections with exact sizes, and other convenience methods
    NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

    • Method Detail

      • newHashMap

        public static <K,​V> HashMap<K,​V> newHashMap​(int size)
        Returns a new HashMap sized to contain size items without resizing the internal array.

      • newLinkedHashMap

        public static <K,​V> LinkedHashMap<K,​V> newLinkedHashMap​(int size)
        Returns a new LinkedHashMap sized to contain size items without resizing the internal array.

      • newHashSet

        public static <E> HashSet<E> newHashSet​(int size)
        Returns a new HashSet sized to contain size items without resizing the internal array.

      • isEmpty

        public static boolean isEmpty​(Collection<?> collection)

      • isNotEmpty

        public static boolean isNotEmpty​(Collection<?> collection)