de.gsi.dataset.utils

Class CircularBuffer<E>

java.lang.Object

de.gsi.dataset.utils.CircularBuffer<E>

Type Parameters:

E - the generic Object to be stored

public class CircularBuffer<E>
extends Object

simple circular ring buffer implementation for generic object type (with read == write position)

Author:

rstein

Constructor Summary

Constructors

Constructor and Description
CircularBuffer(E[] initalElements, int capacity)
CircularBuffer(int capacity)

Method Summary

Modifier and Type	Method and Description
int	available()
int	capacity()
E[]	elements(E[] returnVectorType)
E	get()
E[]	get(E[] into, int length)
E[]	get(E[] into, int readPos, int length)
E	get(int readPos)
protected int	getIndex(int readPos)
boolean	isBufferFlipped()
boolean	put(E element)
int	put(E[] newElements, int length) add multiple new elements
int	put(E[] newElements, int startIndex, int length) add multiple new elements
int	remainingCapacity()
E	replace(E element)
E	replace(E element, int atIndex)
void	reset() resets buffer
int	writePosition()

Methods inherited from class java.lang.Object

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

Constructor Detail

CircularBuffer

public CircularBuffer(E[] initalElements,
                      int capacity)

Parameters:

initalElements - adds element the buffer should be initialised with

capacity - maximum capacity of the buffer

CircularBuffer

public CircularBuffer(int capacity)

Parameters:

capacity - maximum capacity of the buffer

Method Detail

available

public int available()

Returns:

number of available buffer elements

capacity

public int capacity()

Returns:

the maximum possible/filled number of available buffer elements

elements

public E[] elements(E[] returnVectorType)

Parameters:

returnVectorType - need to supply export type vector

Returns:

internal field array

get

public E get()

Returns:

value at head

get

public E[] get(E[] into,
               int length)

Parameters:

into - storage container

length - number of elements to be read

Returns:

either into or newly allocated array containing the result

get

public E[] get(E[] into,
               int readPos,
               int length)

Parameters:

into - storage container

readPos - circular index (wraps around)

length - number of elements to be read

Returns:

either into or newly allocated array containing the result

get

public E get(int readPos)

Parameters:

readPos - circular index (wraps around)

Returns:

the value

getIndex

protected int getIndex(int readPos)

isBufferFlipped

public boolean isBufferFlipped()

Returns:

whether write position exceeded at least once the capacity

put

public boolean put(E element)

Parameters:

element - new element

Returns:

true

put

public int put(E[] newElements,
               int length)

add multiple new elements

Parameters:

newElements - array of new elements

length - number of elements that are to be written from array

Returns:

true: write index is smaller than read index

put

public int put(E[] newElements,
               int startIndex,
               int length)

add multiple new elements

Parameters:

newElements - array of new elements

startIndex - 'null'

length - number of elements that are to be written from array

Returns:

true: write index is smaller than read index

remainingCapacity

public int remainingCapacity()

Returns:

number of available buffer elements that can be written before buffer wraps-around

replace

public E replace(E element)

Parameters:

element - to replace an existing element at the head buffer position

Returns:

the previous element stored at that location

replace

public E replace(E element,
                 int atIndex)

Parameters:

element - to replace an existing element at given buffer position

atIndex - index at which to replace the value

Returns:

the previous element stored at that location

reset

public void reset()

resets buffer

writePosition

public int writePosition()

Returns:

internal write position