org.apache.logging.log4j.core.util

Class CyclicBuffer<T>

java.lang.Object

org.apache.logging.log4j.core.util.CyclicBuffer<T>

Type Parameters:

T - The type of object stored in the buffer.

public final class CyclicBuffer<T>
extends java.lang.Object

A bounded buffer containing elements of type T. When the number of elements to be added will exceed the size of the buffer the oldest element will be overwritten. Access to the buffer is thread safe.

Field Summary

Fields

Modifier and Type	Field and Description
private java.lang.Class<T>	clazz
private int	first
private int	last
private int	numElems
private T[]	ring

Constructor Summary

Constructors

Constructor and Description
CyclicBuffer(java.lang.Class<T> clazz, int size) Instantiates a new CyclicBuffer of at most maxSize events.

Method Summary

Modifier and Type	Method and Description
void	add(T item) Adds an item as the last event in the buffer.
boolean	isEmpty() Determines if the buffer contains elements.
private T[]	makeArray(java.lang.Class<T> cls, int size)
T[]	removeAll() Removes all the elements from the buffer and returns them.

Methods inherited from class java.lang.Object

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

Field Detail

ring

private final T[] ring

first

private int first

last

private int last

numElems

private int numElems

clazz

private final java.lang.Class<T> clazz

Constructor Detail

CyclicBuffer

public CyclicBuffer(java.lang.Class<T> clazz,
                    int size)
             throws java.lang.IllegalArgumentException

Instantiates a new CyclicBuffer of at most maxSize events.

Parameters:

clazz - The Class associate with the type of object in the buffer.

size - The number of items in the buffer.

Throws:

java.lang.IllegalArgumentException - if the size is negative.

Method Detail

makeArray

private T[] makeArray(java.lang.Class<T> cls,
                      int size)

add

public void add(T item)

Adds an item as the last event in the buffer.

Parameters:

item - The item to add to the buffer.

removeAll

public T[] removeAll()

Removes all the elements from the buffer and returns them.

Returns:

An array of the elements in the buffer.

isEmpty

public boolean isEmpty()

Determines if the buffer contains elements.

Returns:

true if the buffer is empty, false otherwise.