org.jnetpcap.packet
Class JHeader

java.lang.Object
  org.jnetpcap.nio.JMemory
      org.jnetpcap.nio.JBuffer
          org.jnetpcap.packet.JHeader

All Implemented Interfaces:

JByteBuffer

Direct Known Subclasses:

Ethernet, Html, IEEE802dot1q, IEEE802dot2, IEEE802dot3, IEEESnap, Ip6, JHeaderMap, JMappedHeader, JSubHeader, L2TP, Payload, PPP, Tcp, Udp

public abstract class JHeader
extends JBuffer

A base class for all protocol header definitions.

Author:

Mark Bednarczyk, Sly Technologies, Inc.

Nested Class Summary

static class

JHeader.State This class is peered state of a header a native state structure

Nested classes/interfaces inherited from class org.jnetpcap.nio.JMemory

JMemory.Type

Field Summary

protected AnnotatedHeader	annotatedHeader
protected static JHeader[]	EMPTY_HEADER_ARRAY
protected boolean	isSubHeader
protected JPacket	packet A reference to the packet that this header is part of
protected JHeader.State	state Reference to header's native state structure

Fields inherited from class org.jnetpcap.nio.JMemory

JNETPCAP_LIBRARY_NAME

Constructor Summary

JHeader()
Calls on the header defintion's static annotated \@HeaderLength method to get header's length.

JHeader(int id, JField[] fields, java.lang.String name)
Constructs a header and initializes its static fields

JHeader(int id, JField[] fields, java.lang.String name, java.lang.String nicname)
Constructs a header and initializes its static fields

JHeader(int id, java.lang.String name)
Constructs a header.

JHeader(int id, java.lang.String name, java.lang.String nicname)
Constructs a header.

JHeader(JHeader.State state, JField[] fields, java.lang.String name, java.lang.String nicname)
Constructs a header and initializes its static fields

JHeader(JProtocol protocol)

Method Summary

void	addAnalysis(JAnalysis analysis)
void	decode() Method that gets called everytime a header is successfully peered with new buffer and/or state structure.
protected void	decodeHeader() Allows a header to decode its complex fields
<T extends JAnalysis> T	getAnalysis(T analysis)
java.lang.Iterable<JAnalysis>	getAnalysisIterable()
AnnotatedHeader	getAnnotatedHeader()
java.lang.String	getDescription()
JField[]	getFields() Retrieves the fields at runtime, that this header has so that they may be used by a formatter
int	getId() Gets the numerical ID of this protocol header at runtime as assigned by the JRegistry
int	getLength() Length of this header within the buffer
java.lang.String	getName() Gets the comprehensive name for this header
java.lang.String	getNicname() Gets the short name for this header
int	getOffset() Offset into the packet buffer
JPacket	getPacket() Gets the packet that this header is associated with
JHeader	getParent()
JHeader.State	getState() Gets the reference to the current header's native state structure
JHeader[]	getSubHeaders() Gets an array of currently defined sub headers
int	getType()
boolean	hasAnalysis(java.lang.Class<? extends JAnalysis> analysis)
boolean	hasAnalysis(int type)
<T extends JAnalysis> boolean	hasAnalysis(T analysis)
boolean	hasDescription()
boolean	hasSubHeaders()
int	peer(JBuffer buffer, int offset)
int	peer(JHeader header) Peers, associates a native packet buffer and scanner structure with this header.
void	setPacket(JPacket packet) Sets the packet that this header should be associated with
void	setSubHeaders(JHeader[] headers)
static int	sizeof() Gets the size of the native header_t structure on this particular platform
java.lang.String	toString() Gets a string with summary information about the header.
protected void	validateHeader() Allows a header to validate its values

Methods inherited from class org.jnetpcap.nio.JBuffer

findUTF8String, getByte, getByteArray, getByteArray, getDouble, getFloat, getInt, getLong, getShort, getUByte, getUInt, getUShort, getUTF8Char, getUTF8String, getUTF8String, getUTF8String, getUTF8String, isReadonly, order, order, peer, peer, peer, peer, setByte, setByteArray, setByteBuffer, setDouble, setFloat, setInt, setLong, setShort, setUByte, setUInt, setUShort, transferFrom, transferFrom, transferFrom, transferTo, transferTo, transferTo

Methods inherited from class org.jnetpcap.nio.JMemory

check, cleanup, finalize, isInitialized, isJMemoryBasedOwner, isOwner, peer, setSize, size, toDebugString, toHexdump, toHexdump, totalActiveAllocated, totalAllocateCalls, totalAllocated, totalAllocatedSegments0To255Bytes, totalAllocatedSegments256OrAbove, totalDeAllocateCalls, totalDeAllocated, transferFrom, transferFrom, transferFromDirect, transferOwnership, transferTo, transferTo, transferTo, transferTo, transferTo

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.jnetpcap.nio.JByteBuffer

size

Field Detail

EMPTY_HEADER_ARRAY

protected static final JHeader[] EMPTY_HEADER_ARRAY

annotatedHeader

protected AnnotatedHeader annotatedHeader

isSubHeader

protected boolean isSubHeader

packet

protected JPacket packet

A reference to the packet that this header is part of

state

protected final JHeader.State state

Reference to header's native state structure

Constructor Detail

JHeader

public JHeader()

Calls on the header defintion's static annotated \@HeaderLength method to get header's length. The method is given a buffer and offset as the start of the header. The method invoked must be defined in the header definition otherwise an exception will be thrown.

JHeader

public JHeader(int id,
               JField[] fields,
               java.lang.String name)

Constructs a header and initializes its static fields

Parameters:

id - numerical ID of the protocol

fields - fields usd by the formatter to reformat the packet for output

name - comprehensive name of the protocol

JHeader

public JHeader(int id,
               JField[] fields,
               java.lang.String name,
               java.lang.String nicname)

Constructs a header and initializes its static fields

Parameters:

id - numerical ID of the protocol

fields - fields usd by the formatter to reformat the packet for output

name - comprehensive name of the protocol

nicname - a short name for the protocol

JHeader

public JHeader(int id,
               java.lang.String name)

Constructs a header.

Parameters:

id - numerical ID of the protocol

name - comprehensive name of the protocol

JHeader

public JHeader(int id,
               java.lang.String name,
               java.lang.String nicname)

Constructs a header.

Parameters:

id - numerical ID of the protocol

name - comprehensive name of the protocol

nicname - a short name for the protocol

JHeader

public JHeader(JProtocol protocol)

JHeader

public JHeader(JHeader.State state,
               JField[] fields,
               java.lang.String name,
               java.lang.String nicname)

Constructs a header and initializes its static fields

Parameters:

state - the default header state object being referenced

fields - fields usd by the formatter to reformat the packet for output

name - comprehensive name of the protocol

nicname - a short name for the protocol

Method Detail

sizeof

public static int sizeof()

Gets the size of the native header_t structure on this particular platform

Returns:

length in bytes

decode

public final void decode()

Method that gets called everytime a header is successfully peered with new buffer and/or state structure. This method in JHeader is empty and is expected to be overriden by subclasses of JHeader that require special processing of the header such as decoding its structure at runtime when the header object is bound to new state.

decodeHeader

protected void decodeHeader()

Allows a header to decode its complex fields

addAnalysis

public void addAnalysis(JAnalysis analysis)

getAnalysis

public <T extends JAnalysis> T getAnalysis(T analysis)

getAnnotatedHeader

public AnnotatedHeader getAnnotatedHeader()

Returns:

getDescription

public java.lang.String getDescription()

Returns:

getFields

public JField[] getFields()

Retrieves the fields at runtime, that this header has so that they may be used by a formatter

Returns:

an array of fields that this header is made up of, as determined at runtime

getId

public final int getId()

Gets the numerical ID of this protocol header at runtime as assigned by the JRegistry

Returns:

unique numerical ID of this header

getLength

public int getLength()

Length of this header within the buffer

Returns:

length in bytes

getName

public final java.lang.String getName()

Gets the comprehensive name for this header

Returns:

the name full name of this header

getNicname

public final java.lang.String getNicname()

Gets the short name for this header

Returns:

the nicname for this header

getOffset

public int getOffset()

Offset into the packet buffer

Returns:

offset into the buffer in bytes

getPacket

public final JPacket getPacket()

Gets the packet that this header is associated with

Returns:

parent packet

getParent

public JHeader getParent()

getState

public JHeader.State getState()

Gets the reference to the current header's native state structure

Returns:

current state of the header

getSubHeaders

public JHeader[] getSubHeaders()

Gets an array of currently defined sub headers

Returns:

array of sub headers

getType

public int getType()

hasAnalysis

public boolean hasAnalysis(int type)

hasAnalysis

public boolean hasAnalysis(java.lang.Class<? extends JAnalysis> analysis)

hasAnalysis

public <T extends JAnalysis> boolean hasAnalysis(T analysis)

hasDescription

public boolean hasDescription()

Returns:

hasSubHeaders

public boolean hasSubHeaders()

peer

public int peer(JBuffer buffer,
                int offset)

peer

public int peer(JHeader header)

Peers, associates a native packet buffer and scanner structure with this header. This header is unchanged while the header being passed in is rereferenced to point at this headers buffer and state structure.

Parameters:

header - the header to peer with this header

Returns:

number of bytes total that were peered with the supplied header

setPacket

public final void setPacket(JPacket packet)

Sets the packet that this header should be associated with

Parameters:

packet - packet to associate with this header

setSubHeaders

public void setSubHeaders(JHeader[] headers)

toString

public java.lang.String toString()

Gets a string with summary information about the header.

Overrides:

toString in class java.lang.Object

Returns:

String with summary of the header

validateHeader

protected void validateHeader()

Allows a header to validate its values

getAnalysisIterable

public java.lang.Iterable<JAnalysis> getAnalysisIterable()

Returns: