Module org.omnifaces.utils
Package org.omnifaces.utils

Class Collections

java.lang.Object
org.omnifaces.utils.Collections
public final class Collections extends Object

  • Method Details

    • unmodifiableSet

      public static <E> Set<E> unmodifiableSet(Object... values)
      Creates an unmodifiable set based on the given values. If one of the values is an instance of an array or a collection, then each of its values will also be merged into the set. Nested arrays or collections will result in a ClassCastException.
      Type Parameters:
      E - The expected set element type.
      Parameters:
      values - The values to create an unmodifiable set for.
      Returns:
      An unmodifiable set based on the given values.
      Throws:
      ClassCastException - When one of the values or one of the arrays or collections is of wrong type.

    • iterableToList

      public static <E> List<E> iterableToList(Iterable<E> iterable)
      Converts an iterable into a list.

      This method makes NO guarantee to whether changes to the source iterable are reflected in the returned list or not. For instance if the given iterable already is a list, it's returned directly.

      Type Parameters:
      E - The generic iterable element type.
      Parameters:
      iterable - The iterable to be converted.
      Returns:
      The list representation of the given iterable, possibly the same instance as that iterable.

    • reverse

      public static <T> Map<T,T> reverse(Map<T,T> source)
      Returns a new map that contains the reverse of the given map.

      The reverse of a map means that every value X becomes a key X' with as corresponding value Y' the key Y that was originally associated with the value X.

      Type Parameters:
      T - The generic map key/value type.
      Parameters:
      source - the map that is to be reversed
      Returns:
      the reverse of the given map

    • contains

      public static boolean contains(Collection<?> collection, Object object)
      Returns true if the collection is not null and contains the specified element.
      Parameters:
      collection - the collection to test for the specified element
      object - element to test for in the specified collection
      Returns:
      true if the collection is not null and contains the specified element