org.apache.commons.collections.buffer
Class CircularFifoBuffer<E>
java.lang.Object
java.util.AbstractCollection<E>
org.apache.commons.collections.buffer.BoundedFifoBuffer<E>
org.apache.commons.collections.buffer.CircularFifoBuffer<E>
- All Implemented Interfaces:
- Serializable, Iterable<E>, Collection<E>, BoundedCollection<E>, Buffer<E>
public class CircularFifoBuffer<E>
- extends BoundedFifoBuffer<E>
CircularFifoBuffer is a first in first out buffer with a fixed size that
replaces its oldest element if full.
The removal order of a CircularFifoBuffer
is based on the
insertion order; elements are removed in the same order in which they
were added. The iteration order is the same as the removal order.
The add(Object)
, BoundedFifoBuffer.remove()
and BoundedFifoBuffer.get()
operations
all perform in constant time. All other operations perform in linear
time or worse.
Note that this implementation is not synchronized. The following can be
used to provide synchronized access to your CircularFifoBuffer
:
Buffer fifo = BufferUtils.synchronizedBuffer(new CircularFifoBuffer());
This buffer prevents null objects from being added.
This class is Serializable from Commons Collections 3.1.
- Since:
- Commons Collections 3.0
- Version:
- $Revision: 1.1.1.1 $ $Date: 2005/05/23 04:33:52 $
- Author:
- Stefano Fornari, Matt Hall, John Watkinson, Stephen Colebourne
- See Also:
- Serialized Form
Method Summary |
boolean |
add(E element)
If the buffer is full, the least recently added element is discarded so
that a new element can be inserted. |
CircularFifoBuffer
public CircularFifoBuffer()
- Constructor that creates a buffer with the default size of 32.
CircularFifoBuffer
public CircularFifoBuffer(int size)
- Constructor that creates a buffer with the specified size.
- Parameters:
size
- the size of the buffer (cannot be changed)
- Throws:
IllegalArgumentException
- if the size is less than 1
CircularFifoBuffer
public CircularFifoBuffer(Collection<E> coll)
- Constructor that creates a buffer from the specified collection.
The collection size also sets the buffer size
- Parameters:
coll
- the collection to copy into the buffer, may not be null
- Throws:
NullPointerException
- if the collection is null
add
public boolean add(E element)
- If the buffer is full, the least recently added element is discarded so
that a new element can be inserted.
- Specified by:
add
in interface Collection<E>
- Overrides:
add
in class BoundedFifoBuffer<E>
- Parameters:
element
- the element to add
- Returns:
- true, always
Copyright © 2005-2005 Apache Software Foundation, Matt Hall, John Watkinson. All Rights Reserved.