Class Collections


  • public class Collections
    extends java.lang.Object
    Class that provides static utility methods for working with collections.
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static <K,​V>
      java.util.Map.Entry<K,​V>
      entry​(K key, V value)
      Creates an immutable map entry.
      static <E> java.util.List<E> listOf​(E... elements)
      Creates an immutable list of elements.
      static <K,​V>
      java.util.Map<K,​V>
      mapOf​(java.util.Map.Entry<K,​V>... entries)
      Creates an immutable map of entries.
      static <T> T valueAt​(java.lang.Object root, java.lang.Object... path)
      Returns the value at a given path.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Method Detail

      • listOf

        @SafeVarargs
        public static <E> java.util.List<E> listOf​(E... elements)
        Creates an immutable list of elements.
        Type Parameters:
        E - The type of the elements in the list.
        Parameters:
        elements - The list elements.
        Returns:
        An immutable list containing the provided elements.
      • mapOf

        @SafeVarargs
        public static <K,​V> java.util.Map<K,​V> mapOf​(java.util.Map.Entry<K,​V>... entries)
        Creates an immutable map of entries.
        Type Parameters:
        K - The key type.
        V - The value type.
        Parameters:
        entries - The map entries.
        Returns:
        An immutable map containing the provided entries.
      • entry

        public static <K,​V> java.util.Map.Entry<K,​V> entry​(K key,
                                                                       V value)
        Creates an immutable map entry.
        Type Parameters:
        K - The key type.
        V - The value type.
        Parameters:
        key - The entry key.
        value - The entry value.
        Returns:
        An immutable map entry containing the provided key/value pair.
      • valueAt

        public static <T> T valueAt​(java.lang.Object root,
                                    java.lang.Object... path)
        Returns the value at a given path.
        Type Parameters:
        T - The type of the value to return.
        Parameters:
        root - The root object.
        path - The path to the value.
        Returns:
        The value at the given path, or null if the value does not exist.