Package org.apache.commons.collections

Class UnboundedFifoBuffer

  • All Implemented Interfaces:
    java.lang.Iterable, java.util.Collection, Buffer
    public class UnboundedFifoBuffer
extends java.util.AbstractCollection
implements Buffer
    Deprecated.
    Moved to buffer subpackage. Due to be removed in v4.0.
    UnboundedFifoBuffer is a very efficient buffer implementation. According to performance testing, it exhibits a constant access time, but it also outperforms ArrayList when used for the same purpose.

    The removal order of an UnboundedFifoBuffer 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 remove() and get() operations perform in constant time. The add(Object) operation performs in amortized 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 UnboundedFifoBuffer: 

       Buffer fifo = BufferUtils.synchronizedBuffer(new UnboundedFifoBuffer());

    This buffer prevents null objects from being added.

    Since:
    Commons Collections 2.1

    • Constructor Summary

      Constructors 
      Constructor Description
      UnboundedFifoBuffer()
      Deprecated.
      Constructs an UnboundedFifoBuffer with the default number of elements.
      UnboundedFifoBuffer​(int initialSize)
      Deprecated.
      Constructs an UnboundedFifoBuffer with the specified number of elements.

    • Method Summary

      All Methods Instance Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      boolean add​(java.lang.Object obj)
      Deprecated.
      Adds the given element to this buffer.
      java.lang.Object get()
      Deprecated.
      Returns the next object in the buffer.
      boolean isEmpty()
      Deprecated.
      Returns true if this buffer is empty; false otherwise.
      java.util.Iterator iterator()
      Deprecated.
      Returns an iterator over this buffer's elements.
      java.lang.Object remove()
      Deprecated.
      Removes the next object from the buffer
      int size()
      Deprecated.
      Returns the number of elements stored in the buffer.

      • Methods inherited from class java.util.AbstractCollection

        addAll, clear, contains, containsAll, remove, removeAll, retainAll, toArray, toArray, toString

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

      • Methods inherited from interface java.util.Collection

        addAll, clear, contains, containsAll, equals, hashCode, parallelStream, remove, removeAll, removeIf, retainAll, spliterator, stream, toArray, toArray, toArray

      • Methods inherited from interface java.lang.Iterable

        forEach

    • Constructor Detail

      • UnboundedFifoBuffer

        public UnboundedFifoBuffer()
        Deprecated.
        Constructs an UnboundedFifoBuffer with the default number of elements. It is exactly the same as performing the following: 
           new UnboundedFifoBuffer(32);

      • UnboundedFifoBuffer

        public UnboundedFifoBuffer​(int initialSize)
        Deprecated.
        Constructs an UnboundedFifoBuffer with the specified number of elements. The integer must be a positive integer.
        Parameters:
        initialSize - the initial size of the buffer
        Throws:
        java.lang.IllegalArgumentException - if the size is less than 1

    • Method Detail

      • size

        public int size()
        Deprecated.
        Returns the number of elements stored in the buffer.
        Specified by:
        size in interface java.util.Collection
        Specified by:
        size in class java.util.AbstractCollection
        Returns:
        this buffer's size

      • isEmpty

        public boolean isEmpty()
        Deprecated.
        Returns true if this buffer is empty; false otherwise.
        Specified by:
        isEmpty in interface java.util.Collection
        Overrides:
        isEmpty in class java.util.AbstractCollection
        Returns:
        true if this buffer is empty

      • add

        public boolean add​(java.lang.Object obj)
        Deprecated.
        Adds the given element to this buffer.
        Specified by:
        add in interface java.util.Collection
        Overrides:
        add in class java.util.AbstractCollection
        Parameters:
        obj - the element to add
        Returns:
        true, always
        Throws:
        java.lang.NullPointerException - if the given element is null
        BufferOverflowException - if this buffer is full

      • get

        public java.lang.Object get()
        Deprecated.
        Returns the next object in the buffer.
        Specified by:
        get in interface Buffer
        Returns:
        the next object in the buffer
        Throws:
        BufferUnderflowException - if this buffer is empty

      • remove

        public java.lang.Object remove()
        Deprecated.
        Removes the next object from the buffer
        Specified by:
        remove in interface Buffer
        Returns:
        the removed object
        Throws:
        BufferUnderflowException - if this buffer is empty

      • iterator

        public java.util.Iterator iterator()
        Deprecated.
        Returns an iterator over this buffer's elements.
        Specified by:
        iterator in interface java.util.Collection
        Specified by:
        iterator in interface java.lang.Iterable
        Specified by:
        iterator in class java.util.AbstractCollection
        Returns:
        an iterator over this buffer's elements