org.jscsi.parser.datasegment

Class AbstractDataSegment

java.lang.Object

org.jscsi.parser.datasegment.AbstractDataSegment

All Implemented Interfaces:

IDataSegment

public abstract class AbstractDataSegment
extends Object
implements IDataSegment

DataSegment

This class represents a basic interface for a data segment contained in a ProtocolDataUnit object.

Author:

Volker Wildi

Field Summary

Fields

Modifier and Type	Field and Description
protected ByteBuffer	dataBuffer The buffer of this data segment.
protected int	length The number of bytes actually used by the dataBuffer.

Constructor Summary

Constructors

Constructor and Description
AbstractDataSegment(int initMaxChunkSize) Constructor to create a new, empty DataSegment object with the given chunk size.

Method Summary

Methods

Modifier and Type	Method and Description
protected static int	calcPadding(int len) This methods calculates the number of padding bytes of the given length.
void	clear() Clears all made settings of this object.
boolean	equals(Object anObject) Compares this object with another object for equality.
int	getLength() Returns the length, which is really used by the dataBuffer.
SettingsMap	getSettings() Returns a SettingsMap instance of this IDataSegment instance.
static int	getTotalLength(int len) Returns the total length (with padding), which is needed for the given length len.
int	hashCode()
org.jscsi.parser.datasegment.AbstractDataSegment.DataSegmentIterator	iterator() Returns an iterator over the chunks of this data segment in proper sequence.
protected void	resizeBuffer(int additionalLength, boolean copyData) This method resizes the data buffer, if necessary.
int	serialize(ByteBuffer dst, int off) This method exports the data buffer to the given ByteBuffer object, which is padded to a integer number of 4 byte words.
int	setDataBuffer(ByteBuffer src, int off, int len) Sets the data buffer to the given buffer src.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.jscsi.parser.datasegment.IDataSegment

append, deserialize

Field Detail

dataBuffer

protected ByteBuffer dataBuffer

The buffer of this data segment.

length

protected int length

The number of bytes actually used by the dataBuffer.

Constructor Detail

AbstractDataSegment

public AbstractDataSegment(int initMaxChunkSize)

Constructor to create a new, empty DataSegment object with the given chunk size.

Parameters:

initMaxChunkSize - The maximum size (in bytes) of one chunk, which represents the MaxRecvDataSegmentLength.

Method Detail

serialize

public int serialize(ByteBuffer dst,
            int off)

This method exports the data buffer to the given ByteBuffer object, which is padded to a integer number of 4 byte words.

Specified by:

serialize in interface IDataSegment

Parameters:

dst - Destination ByteBuffer object.

off - Start position in dst, where to serialize.

Returns:

The number of exported bytes (in bytes).

getSettings

public SettingsMap getSettings()
                        throws InternetSCSIException

Returns a SettingsMap instance of this IDataSegment instance. This is only useful with a TextParameterDataSegment instance.

Specified by:

getSettings in interface IDataSegment

Returns:

The settings of this TextParameterDataSegment instance.

Throws:

InternetSCSIException - if any violation of the iSCSI Standard occurs.

getTotalLength

public static final int getTotalLength(int len)

Returns the total length (with padding), which is needed for the given length len.

Parameters:

len - The length of the DataSegment, which want to be stored.

Returns:

The total length.

resizeBuffer

protected void resizeBuffer(int additionalLength,
                boolean copyData)

This method resizes the data buffer, if necessary. A resizing is not needed, when the neededLength is greater than the capacity of allocated data buffer. The flag copyData indicates, if the old buffer has to be copied into the new bigger data buffer.

Parameters:

additionalLength - The length, which is now needed to store all informations in the data buffer.

copyData - true, if old buffer has to be copied into the new buffer. false indicates, that the new buffer is initialized with zeros.

clear

public void clear()

Clears all made settings of this object. After the call of this method, this object can be reused.

Specified by:

clear in interface IDataSegment

getLength

public final int getLength()

Returns the length, which is really used by the dataBuffer.

Specified by:

getLength in interface IDataSegment

Returns:

The really used length.

equals

public boolean equals(Object anObject)

Compares this object with another object for equality.

Overrides:

equals in class Object

Parameters:

anObject - Another object.

Returns:

true, if the anObject and this object are equal. Else false .

hashCode

public int hashCode()

Overrides:

hashCode in class Object

setDataBuffer

public final int setDataBuffer(ByteBuffer src,
                int off,
                int len)

Sets the data buffer to the given buffer src. Starting from the position offset with length of len.

Specified by:

setDataBuffer in interface IDataSegment

Parameters:

src - The buffer to read from.

off - The start offset to read from.

len - The number of bytes to read.

Returns:

The number of bytes really read.

toString

public final String toString()

Overrides:

toString in class Object

iterator

public final org.jscsi.parser.datasegment.AbstractDataSegment.DataSegmentIterator iterator()

Returns an iterator over the chunks of this data segment in proper sequence.

Specified by:

iterator in interface IDataSegment

Returns:

an iterator over the chunks of this data segment in proper sequence.

calcPadding

protected static final int calcPadding(int len)

This methods calculates the number of padding bytes of the given length. This number of the padding bytes is in the range of 0, ..., BYTES_PER_INT.

Parameters:

len - The length for which the padding bytes are calculated.

Returns:

The number of padding bytes.