de.caff.util

Class ByteRingBuffer

java.lang.Object

de.caff.util.ByteRingBuffer

All Implemented Interfaces:

ByteCollector

public class ByteRingBuffer
extends java.lang.Object
implements ByteCollector

A byte buffer to which you can add data bytes up to a maximum size.

If the buffer overflows you can only retrieve the latest getLimit() bytes.

Since:

August 10, 2022

Author:

Rammi

Field Summary

Fields

Modifier and Type	Field and Description
(package private) static int	INITIAL_LIMIT Initial limit: 1 MiB.

Constructor Summary

Constructors

Constructor and Description
ByteRingBuffer(int limit) Create a ring buffer with the given size.
ByteRingBuffer(int limit, int initialLimit) Create a ring buffer with the given size.

Method Summary

Modifier and Type	Method and Description
void	append(byte[] bytes, int offset, int length) Append the given byte array part to this buffer.
void	append(int value) Append one byte
void	clear() Clear all data.
int	getLimit() Get the limit of this ring buffer.
long	getNumberOfCollectedBytes() Get the total number of bytes appended to this buffer.
int	size() Get the number of valid bytes cached in this buffer.
byte[]	toByteArray() Create a byte array with the bytes in this buffer.
ByteIndexable	toByteIndexable() Get a stable byte indexable from this buffer.
ByteIndexable	view() Get a byte indexable view of this ring buffer.

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.caff.util.ByteCollector

append

Field Detail

INITIAL_LIMIT

static final int INITIAL_LIMIT

Initial limit: 1 MiB.

See Also:

Constant Field Values

Constructor Detail

ByteRingBuffer

public ByteRingBuffer(int limit)

Create a ring buffer with the given size.

Parameters:

limit - size limit of this buffer

ByteRingBuffer

ByteRingBuffer(int limit,
               int initialLimit)

Create a ring buffer with the given size. This allows to set the initial limit for testing.

Parameters:

limit - size limit of this buffer

initialLimit - initial limit

Method Detail

getLimit

public int getLimit()

Get the limit of this ring buffer.

Returns:

buffer limit

size

public int size()

Get the number of valid bytes cached in this buffer.

Returns:

number of bytes cached

append

public void append(int value)

Append one byte

Specified by:

append in interface ByteCollector

Parameters:

value - byte value. Accepts integer for convenience, but will cast the given value to byte.

append

public void append(@NotNull
                   byte[] bytes,
                   int offset,
                   int length)

Append the given byte array part to this buffer.

Specified by:

append in interface ByteCollector

Parameters:

bytes - basic byte array

offset - start offset of the bytes to append

length - number of bytes to append

Throws:

java.lang.IndexOutOfBoundsException - if the parameters define a part which is at least partially outside the bytes

toByteArray

@NotNull
public byte[] toByteArray()

Create a byte array with the bytes in this buffer.

Returns:

byte array of size size() containing with the buffered bytes

view

@NotNull
public ByteIndexable view()

Get a byte indexable view of this ring buffer.

This is more efficient than copying all bytes in toByteArray(), especially if only a few bytes of a larger content are of interest. But the price is high: any change to this buffer can break the returned view. So this is best used on a finished buffer.

Returns:

byte indexable view of this buffer

See Also:

toByteIndexable(), toByteArray()

toByteIndexable

@NotNull
public ByteIndexable toByteIndexable()

Get a stable byte indexable from this buffer.

Compared to view() the returned indexable is decoupled from this buffer, with the price of a copy of the bytes. Compared to the result of

 ByteIndexable.viewArray(ringBuffer.toByteArray())
 

this method provides an already frozen byte indexable.

Returns:

stable frozen byte indexable

See Also:

toByteArray(), view()

clear

public void clear()

Clear all data. This will clear everything but the total number of bytes handled by this buffer.

Specified by:

clear in interface ByteCollector

getNumberOfCollectedBytes

public long getNumberOfCollectedBytes()

Get the total number of bytes appended to this buffer.

Specified by:

getNumberOfCollectedBytes in interface ByteCollector

Returns:

total number of appended bytes