Class ForwardingCollection<E extends @Nullable java.lang.Object>

  • All Implemented Interfaces:
    java.lang.Iterable<E>, java.util.Collection<E>
    Direct Known Subclasses:
    ForwardingList, ForwardingMultiset, ForwardingQueue, ForwardingSet

    public abstract class ForwardingCollection<E extends @Nullable java.lang.Object>
    extends ForwardingObject
    implements java.util.Collection<E>
    A collection which forwards all its method calls to another collection. Subclasses should override one or more methods to modify the behavior of the backing collection as desired per the decorator pattern.

    Warning: The methods of ForwardingCollection forward indiscriminately to the methods of the delegate. For example, overriding add(E) alone will not change the behavior of addAll(java.util.Collection<? extends E>), which can lead to unexpected behavior. In this case, you should override addAll as well, either providing your own implementation, or delegating to the provided standardAddAll method.

    default method warning: This class does not forward calls to default methods. Instead, it inherits their default implementations. When those implementations invoke methods, they invoke methods on the ForwardingCollection.

    The standard methods are not guaranteed to be thread-safe, even when all of the methods that they depend on are thread-safe.

    Kevin Bourrillion, Louis Wasserman