# Package org.apache.commons.collections4.queue

This package contains implementations for the `Queue` interface.

See: Description

- Class Summary
  Class | Description
  --- | ---
  AbstractQueueDecorator<E> | Decorates another `Queue` to provide additional behaviour.
  CircularFifoQueue<E> | CircularFifoQueue is a first-in first-out queue with a fixed size that replaces its oldest element if full.
  PredicatedQueue<E> | Decorates another `Queue` to validate that additions match a specified predicate.
  SynchronizedQueue<E> | Decorates another `Queue` to synchronize its behaviour for a multi-threaded environment.
  TransformedQueue<E> | Decorates another `Queue` to transform objects that are added.
  UnmodifiableQueue<E> | Decorates another `Queue` to ensure it can't be altered.

## Package org.apache.commons.collections4.queue Description

This package contains implementations for the `Queue` interface.

The following implementations are provided in the package:

- CircularFifoQueue - implements a queue with a fixed size that discards oldest when full

The following decorators are provided in the package:

- Predicated - ensures that only elements that are valid according to a predicate can be added
- Transformed - transforms elements added to the queue
- Unmodifiable - ensures the collection cannot be altered

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