org.mortbay.io
Interface Buffer

All Superinterfaces:

Cloneable

All Known Implementing Classes:

AbstractBuffer

public interface Buffer

extends Cloneable

Byte Buffer interface. This is a byte buffer that is designed to work like a FIFO for bytes. Puts and Gets operate on different pointers into the buffer and the valid _content of the buffer is always between the getIndex and the putIndex. This buffer interface is designed to be similar, but not dependant on the java.nio buffers, which may be used to back an implementation of this Buffer. The main difference is that NIO buffer after a put have their valid _content before the position and a flip is required to access that data. For this buffer it is always true that: markValue <= getIndex <= putIndex <= capacity

Version:

1.0

Author:

gregw

Nested Class Summary

static interface

Buffer.CaseInsensitve

Field Summary

static int	IMMUTABLE
static boolean	NON_VOLATILE
static int	READONLY
static int	READWRITE
static boolean	VOLATILE

Method Summary

byte[]	array() Get the underlying array, if one exists.
byte[]	asArray()
Buffer	asImmutableBuffer()
Buffer	asMutableBuffer()
Buffer	asNonVolatileBuffer()
Buffer	asReadOnlyBuffer()
Buffer	buffer() Get the unerlying buffer.
int	capacity() The capacity of the buffer.
void	clear() Clear the buffer.
void	compact() Compact the buffer by discarding bytes before the postion (or mark if set).
boolean	equalsIgnoreCase(Buffer buffer)
byte	get() Get the byte at the current getIndex and increment it.
int	get(byte[] b, int offset, int length) Get bytes from the current postion and put them into the passed byte array.
Buffer	get(int length)
int	getIndex() The index within the buffer that will next be read or written.
boolean	hasContent()
boolean	isImmutable()
boolean	isReadOnly()
boolean	isVolatile()
int	length() The number of bytes from the getIndex to the putIndex
void	mark() Set the mark to the current getIndex.
void	mark(int offset) Set the mark relative to the current getIndex
int	markIndex() The current index of the mark.
byte	peek() Get the byte at the current getIndex without incrementing the getIndex.
byte	peek(int index) Get the byte at a specific index in the buffer.
int	peek(int index, byte[] b, int offset, int length)
Buffer	peek(int index, int length)
int	poke(int index, Buffer src) Put the contents of the buffer at the specific index.
void	poke(int index, byte b) Put a specific byte to a specific getIndex.
int	poke(int index, byte[] b, int offset, int length) Put a specific byte to a specific getIndex.
int	put(Buffer src) Write the bytes from the source buffer to the current getIndex.
void	put(byte b) Put a byte to the current getIndex and increment the getIndex.
int	put(byte[] b) Put a byte to the current getIndex and increment the getIndex.
int	put(byte[] b, int offset, int length) Put a byte to the current getIndex and increment the getIndex.
int	putIndex() The index of the first element that should not be read.
int	readFrom(InputStream in, int max) Read the buffer's contents from the input stream
void	reset() Reset the current getIndex to the mark
void	setGetIndex(int newStart) Set the buffers start getIndex.
void	setMarkIndex(int newMark) Set a specific value for the mark.
void	setPutIndex(int newLimit)
int	skip(int n) Skip _content.
Buffer	slice()
Buffer	sliceFromMark()
Buffer	sliceFromMark(int length)
int	space() the space remaining in the buffer.
String	toDetailString()
void	writeTo(OutputStream out) Write the buffer's contents to the output stream

Field Detail

IMMUTABLE

public static final int IMMUTABLE

See Also:

Constant Field Values

READONLY

public static final int READONLY

See Also:

Constant Field Values

READWRITE

public static final int READWRITE

See Also:

Constant Field Values

VOLATILE

public static final boolean VOLATILE

See Also:

Constant Field Values

NON_VOLATILE

public static final boolean NON_VOLATILE

See Also:

Constant Field Values

Method Detail

array

public byte[] array()

Get the underlying array, if one exists.

Returns:

a byte[] backing this buffer or null if none exists.

asArray

public byte[] asArray()

Returns:

a byte[] value of the bytes from the getIndex to the putIndex.

buffer

public Buffer buffer()

Get the unerlying buffer. If this buffer wraps a backing buffer.

Returns:

The root backing buffer or this if there is no backing buffer;

asNonVolatileBuffer

public Buffer asNonVolatileBuffer()

Returns:

a non volitile version of this Buffer value

asReadOnlyBuffer

public Buffer asReadOnlyBuffer()

Returns:

a readonly version of this Buffer.

asImmutableBuffer

public Buffer asImmutableBuffer()

Returns:

an immutable version of this Buffer.

asMutableBuffer

public Buffer asMutableBuffer()

Returns:

an immutable version of this Buffer.

capacity

public int capacity()

The capacity of the buffer. This is the maximum putIndex that may be set.

Returns:

an int value

space

public int space()

the space remaining in the buffer.

Returns:

capacity - putIndex

clear

public void clear()

Clear the buffer. getIndex=0, putIndex=0.

compact

public void compact()

Compact the buffer by discarding bytes before the postion (or mark if set). Bytes from the getIndex (or mark) to the putIndex are moved to the beginning of the buffer and the values adjusted accordingly.

get

public byte get()

Get the byte at the current getIndex and increment it.

Returns:

The byte value from the current getIndex.

get

public int get(byte[] b,
               int offset,
               int length)

Get bytes from the current postion and put them into the passed byte array. The getIndex is incremented by the number of bytes copied into the array.

Parameters:

b - The byte array to fill.

offset - Offset in the array.

length - The max number of bytes to read.

Returns:

The number of bytes actually read.

get

public Buffer get(int length)

Parameters:

length - an int value

Returns:

a Buffer value

getIndex

public int getIndex()

The index within the buffer that will next be read or written.

Returns:

an int value >=0 <= putIndex()

hasContent

public boolean hasContent()

Returns:

true of putIndex > getIndex

equalsIgnoreCase

public boolean equalsIgnoreCase(Buffer buffer)

Returns:

a boolean value true if case sensitive comparison on this buffer

isImmutable

public boolean isImmutable()

Returns:

a boolean value true if the buffer is immutable and that neither the buffer contents nor the indexes may be changed.

isReadOnly

public boolean isReadOnly()

Returns:

a boolean value true if the buffer is readonly. The buffer indexes may be modified, but the buffer contents may not. For example a View onto an immutable Buffer will be read only.

isVolatile

public boolean isVolatile()

Returns:

a boolean value true if the buffer contents may change via alternate paths than this buffer. If the contents of this buffer are to be used outside of the current context, then a copy must be made.

length

public int length()

The number of bytes from the getIndex to the putIndex

Returns:

an int == putIndex()-getIndex()

mark

public void mark()

Set the mark to the current getIndex.

mark

public void mark(int offset)

Set the mark relative to the current getIndex

Parameters:

offset - an int value to add to the current getIndex to obtain the mark value.

markIndex

public int markIndex()

The current index of the mark.

Returns:

an int index in the buffer or -1 if the mark is not set.

peek

public byte peek()

Get the byte at the current getIndex without incrementing the getIndex.

Returns:

The byte value from the current getIndex.

peek

public byte peek(int index)

Get the byte at a specific index in the buffer.

Parameters:

index - an int value

Returns:

a byte value

peek

public Buffer peek(int index,
                   int length)

Parameters:

index - an int value

length - an int value

Returns:

The Buffer value from the requested getIndex.

peek

public int peek(int index,
                byte[] b,
                int offset,
                int length)

Parameters:

index - an int value

b - The byte array to peek into

offset - The offset into the array to start peeking

length - an int value

Returns:

The number of bytes actually peeked

poke

public int poke(int index,
                Buffer src)

Put the contents of the buffer at the specific index.

Parameters:

index - an int value

src - a Buffer. If the source buffer is not modified

Returns:

The number of bytes actually poked

poke

public void poke(int index,
                 byte b)

Put a specific byte to a specific getIndex.

Parameters:

index - an int value

b - a byte value

poke

public int poke(int index,
                byte[] b,
                int offset,
                int length)

Put a specific byte to a specific getIndex.

Parameters:

index - an int value

b - a byte array value

Returns:

The number of bytes actually poked

put

public int put(Buffer src)

Write the bytes from the source buffer to the current getIndex.

Parameters:

src - The source Buffer it is not modified.

Returns:

The number of bytes actually poked

put

public void put(byte b)

Put a byte to the current getIndex and increment the getIndex.

Parameters:

b - a byte value

put

public int put(byte[] b,
               int offset,
               int length)

Put a byte to the current getIndex and increment the getIndex.

Parameters:

b - a byte value

Returns:

The number of bytes actually poked

put

public int put(byte[] b)

Put a byte to the current getIndex and increment the getIndex.

Parameters:

b - a byte value

Returns:

The number of bytes actually poked

putIndex

public int putIndex()

The index of the first element that should not be read.

Returns:

an int value >= getIndex()

reset

public void reset()

Reset the current getIndex to the mark

setGetIndex

public void setGetIndex(int newStart)

Set the buffers start getIndex.

Parameters:

newStart - an int value

setMarkIndex

public void setMarkIndex(int newMark)

Set a specific value for the mark.

Parameters:

newMark - an int value

setPutIndex

public void setPutIndex(int newLimit)

Parameters:

newLimit - an int value

skip

public int skip(int n)

Skip _content. The getIndex is updated by min(remaining(), n)

Parameters:

n - The number of bytes to skip

Returns:

the number of bytes skipped.

slice

public Buffer slice()

Returns:

a volitile Buffer from the postion to the putIndex.

sliceFromMark

public Buffer sliceFromMark()

Returns:

a volitile Buffer value from the mark to the putIndex

sliceFromMark

public Buffer sliceFromMark(int length)

Parameters:

length - an int value

Returns:

a valitile Buffer value from the mark of the length requested.

toDetailString

public String toDetailString()

Returns:

a String value describing the state and contents of the buffer.

writeTo

public void writeTo(OutputStream out)
             throws IOException

Write the buffer's contents to the output stream

Parameters:

out -

Throws:

IOException

readFrom

public int readFrom(InputStream in,
                    int max)
             throws IOException

Read the buffer's contents from the input stream

Parameters:

in - input stream

max - maximum number of bytes that may be read

Returns:

actual number of bytes read or -1 for EOF

Throws:

IOException