org.limewire.collection
Class Buffer<E>

java.lang.Object
  org.limewire.collection.Buffer<E>

All Implemented Interfaces:

Cloneable, Iterable<E>

Direct Known Subclasses:

NumericBuffer

public class Buffer<E>
extends Object
implements Cloneable, Iterable<E>

Provides a simple fixed-size double-ended queue, a circular buffer. The fixed size is intentional for performance; use Buffer when you want to use a fix amount of resources. For a minimal amount of efficiency, the internal buffer is only allocated on the first insertion or retrieval, allowing lots of Buffers to be created that may not be used.

This class is not thread-safe.

Field Summary

protected E[]

buf

Constructor Summary

Buffer(Buffer<? extends E> other)
"Copy constructor": constructs a new shallow copy of other.

Buffer(int size)

Method Summary

E	add(E x) Same as addFirst(x).
E	addFirst(E x)
E	addLast(E x)
void	clear()
Buffer<E>	clone() Returns a shallow copy of this, of type Buffer
boolean	contains(Object x) Returns true if the input object x is in the buffer.
protected E[]	createArray(int size)
E	first() Returns the head of this, or throws NoSuchElementException if this is empty.
E	get(int i) If i<0 or i>=getSize(), throws IndexOutOfBoundsException.
int	getCapacity() Returns the number of elements that this can hold, i.e., the max size that was passed to the constructor.
int	getSize() Returns the number of elements in this.
protected void	initialize() Initializes the internal buf if necessary.
boolean	isEmpty() Returns true if and only if this is empty.
boolean	isFull() Returns true if and only if this is full, e.g., adding another element would force another out.
Iterator<E>	iterator()
E	last() Returns the tail of this, or throws NoSuchElementException if this is empty.
E	remove(int i)
boolean	remove(Object x)
boolean	removeAll(Object x)
E	removeFirst()
E	removeLast()
void	set(int i, E o)
int	size() Same as getSize().
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

buf

protected E[] buf

Constructor Detail

Buffer

public Buffer(int size)

Buffer

public Buffer(Buffer<? extends E> other)

"Copy constructor": constructs a new shallow copy of other.

Method Detail

createArray

protected E[] createArray(int size)

initialize

protected void initialize()

Initializes the internal buf if necessary.

isEmpty

public boolean isEmpty()

Returns true if and only if this is empty.

isFull

public boolean isFull()

Returns true if and only if this is full, e.g., adding another element would force another out.

size

public final int size()

Same as getSize().

getSize

public int getSize()

Returns the number of elements in this. Note that this never exceeds the value returned by getCapacity.

getCapacity

public int getCapacity()

Returns the number of elements that this can hold, i.e., the max size that was passed to the constructor.

get

public E get(int i)
      throws IndexOutOfBoundsException

If i<0 or i>=getSize(), throws IndexOutOfBoundsException. Else returns this[i]

Throws:

IndexOutOfBoundsException

set

public void set(int i,
                E o)
         throws IndexOutOfBoundsException

Throws:

IndexOutOfBoundsException

add

public E add(E x)

Same as addFirst(x).

addFirst

public E addFirst(E x)

addLast

public E addLast(E x)

contains

public boolean contains(Object x)

Returns true if the input object x is in the buffer.

first

public E first()
        throws NoSuchElementException

Returns the head of this, or throws NoSuchElementException if this is empty.

Throws:

NoSuchElementException

last

public E last()
       throws NoSuchElementException

Returns the tail of this, or throws NoSuchElementException if this is empty.

Throws:

NoSuchElementException

removeFirst

public E removeFirst()
              throws NoSuchElementException

Throws:

NoSuchElementException

removeLast

public E removeLast()
             throws NoSuchElementException

Throws:

NoSuchElementException

remove

public E remove(int i)
         throws IndexOutOfBoundsException

Throws:

IndexOutOfBoundsException

remove

public boolean remove(Object x)

removeAll

public boolean removeAll(Object x)

clear

public void clear()

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Iterable<E>

clone

public Buffer<E> clone()
                throws CloneNotSupportedException

Returns a shallow copy of this, of type Buffer

Overrides:

clone in class Object

Throws:

CloneNotSupportedException

toString

public String toString()

Overrides:

toString in class Object