Packet (vtn 0.7.3-SNAPSHOT API)

java.lang.Object
- org.opendaylight.vtn.manager.packet.Packet

All Implemented Interfaces:

Cloneable

Direct Known Subclasses:

ARP, EtherTypePacket, ICMP, IPv4, PortPacket
```
public abstract class Packet
extends Object
implements Cloneable
```
Packet is an abstract class which represents the generic network packet object.
It provides the basic methods which are common for all the packets, like serialize and deserialize.

This class is provided only for VTN internal use. This class may be changed without any notice.

Since:

Beryllium

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

protected static class Packet.HeaderField
HeaderField describes the location of the header field in the packet header.

Nested Classes
Modifier and Type	Class and Description
`protected static class`	`Packet.HeaderField` `HeaderField` describes the location of the header field in the packet header.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`Packet`	`clone()` Return a deep copy of this packet.
`Packet`	`deserialize(byte[] data, int bitOffset, int size)` This method deserializes the data bits obtained from the wire into the respective header and payload which are of type Packet.
`boolean`	`equals(Object o)` Determine whether the given object is identical to this object.
`protected boolean`	`equalsField(String name, byte[] value1, byte[] value2)` Compare the given header field values.
`protected byte`	`getByte(String name)` Return the value of the specified field as a byte.
`protected byte[]`	`getBytes(String name)` Return the value of the specified field as a byte array.
`int`	`getFieldNumBits(String name)` This method fetches the number of bits for header field specified by `name`.
`protected int`	`getFieldNumBits(String name, Packet.HeaderField entry)` Return the number of bits in the header field configured in the given instance.
`int`	`getFieldOffset(String name)` This method fetches the start bit offset for header field specified by `name`.
`protected int`	`getFieldOffset(String name, Packet.HeaderField entry)` Return the offset of the header field configured in the given instance.
`protected Map<String,byte[]>`	`getHeaderFieldMap()` Return a map that keeps packet header fields.
`protected abstract Map<String,Packet.HeaderField>`	`getHeaderFormat()` Return a map that determines the format of the packet.
`int`	`getHeaderSize()` Gets the header length in bits.
`protected int`	`getInt(String name)` Return the value of the specified field as an integer.
`protected Ip4Network`	`getIp4Network(String name)` Return the value of the specified field as an IPv4 address.
`Packet`	`getPayload()` Return the packet encapsulated by this packet.
`byte[]`	`getRawPayload()` Returns the raw payload carried by this packet in case payload was not parsed.
`protected int`	`getRawPayloadSize()` Return the size of the raw payload in this packet.
`protected short`	`getShort(String name)` Return the value of the specified field as a short integer.
`int`	`hashCode()` Return the hash code of this object.
`boolean`	`isCorrupted()` Return whether the deserialized packet is to be considered corrupted.
`protected boolean`	`isZeroShort(byte[] value)` Determine whether the given value represents a zero short value or not.
`protected void`	`postDeserializeCustomOperation(byte[] data, int offset)` This method re-computes the checksum of the bits received on the wire and validates it with the checksum in the bits received.
`protected void`	`postSerializeCustomOperation(byte[] myBytes)` This method gets called at the end of the serialization process.
`byte[]`	`serialize()` This method serializes the header and payload from the respective packet class, into a single stream of bytes to be sent on the wire.
`protected void`	`setCorrupted(boolean c)` Set a boolean value which determines whether this packet is corrupted or not.
`protected void`	`setHeaderField(String name, byte[] value)` Associate the specified value with the specified header field.
`void`	`setPayload(Packet p)` Set the packet encapsulated by this packet.
`protected void`	`setPayloadClass(Class<? extends Packet> cls)` Set a class that specifies the type of packets encapsulated by this packet.
`void`	`setRawPayload(byte[] bytes)` Set a raw payload in the packet class.
`String`	`toString()` Return a string representation of this object.

Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait

- Method Detail
  - getPayload
```
public final Packet getPayload()
```
    Return the packet encapsulated by this packet.
    
    Returns:
    
    The packet encapsulated by this packet if present. null if not present.
  - setPayload
```
public void setPayload(Packet p)
```
    Set the packet encapsulated by this packet.
    
    Parameters:
    
    p - The packet encapsulated by this packet.
  - deserialize
```
public Packet deserialize(byte[] data,
                          int bitOffset,
                          int size)
                   throws PacketException
```
    This method deserializes the data bits obtained from the wire into the respective header and payload which are of type Packet.
    
    Parameters:
    
    data - Data from wire to deserialize.
    
    bitOffset - Bit position where packet header starts in data array.
    
    size - Size of packet in bits.
    
    Returns:
    
    This instance.
    
    Throws:
    
    PacketException - An error occurred.
  - serialize
```
public byte[] serialize()
                 throws PacketException
```
    This method serializes the header and payload from the respective packet class, into a single stream of bytes to be sent on the wire.
    
    Returns:
    
    The byte array representing the serialized Packet.
    
    Throws:
    
    PacketException - An error occurred.
  - postSerializeCustomOperation
```
protected void postSerializeCustomOperation(byte[] myBytes)
                                     throws PacketException
```
    This method gets called at the end of the serialization process. It is intended for the child packets to insert some custom data into the output byte stream which cannot be done or cannot be done efficiently during the normal Packet.serialize() path. An example is the checksum computation for IPv4.
    
    Parameters:
    
    myBytes - Serialized bytes.
    
    Throws:
    
    PacketException - An error occurred.
  - postDeserializeCustomOperation
```
protected void postDeserializeCustomOperation(byte[] data,
                                              int offset)
                                       throws PacketException
```
    This method re-computes the checksum of the bits received on the wire and validates it with the checksum in the bits received. Since the computation of checksum varies based on the protocol, this method is overridden. Currently only IPv4 and ICMP do checksum computation and validation. TCP and UDP need to implement these if required.
    
    Parameters:
    
    data - The byte stream representing the Ethernet frame.
    
    offset - The bit offset from where the byte array corresponding to this Packet starts in the frame
    
    Throws:
    
    PacketException - An error occurred.
  - setPayloadClass
```
protected final void setPayloadClass(Class<? extends Packet> cls)
```
    Set a class that specifies the type of packets encapsulated by this packet.
    
    Parameters:
    
    cls - A class that specifies the type of the payload packet.
  - setHeaderField
```
protected void setHeaderField(String name,
                              byte[] value)
```
    Associate the specified value with the specified header field.
    
    Parameters:
    
    name - The name of the header field.
    
    value - The value to be associated with the specified header field. null cannot be specified.
  - getHeaderFieldMap
```
protected final Map<String,byte[]> getHeaderFieldMap()
```
    Return a map that keeps packet header fields.
    
    Returns:
    
    A map that keeps packet header fields.
  - getHeaderSize
```
public int getHeaderSize()
```
    Gets the header length in bits.
    
    Returns:
    
    The header length in bits.
  - getFieldOffset
```
public final int getFieldOffset(String name)
```
    This method fetches the start bit offset for header field specified by name.
    
    Parameters:
    
    name - The name of the header field.
    
    Returns:
    
    The offset of the requested field.
  - getFieldNumBits
```
public final int getFieldNumBits(String name)
```
    This method fetches the number of bits for header field specified by name.
    
    Parameters:
    
    name - The name of the header field.
    
    Returns:
    
    The number of bits of the requested field.
  - getRawPayload
```
public byte[] getRawPayload()
```
    Returns the raw payload carried by this packet in case payload was not parsed. Caller can call this function in case the getPaylod() returns null.
    
    Returns:
    
    The raw payload if not parsable as an array of bytes. null otherwise
  - setRawPayload
```
public void setRawPayload(byte[] bytes)
```
    Set a raw payload in the packet class.
    
    Parameters:
    
    bytes - The raw payload as byte array.
  - isCorrupted
```
public final boolean isCorrupted()
```
    Return whether the deserialized packet is to be considered corrupted. This is the case when the checksum computed after reconstructing the packet received from wire is not equal to the checksum read from the stream. For the Packet class which do not have a checksum field, this function will always return false.
    
    Returns:
    
    true if the deserialized packet's recomputed checksum is not equal to the packet carried checksum
  - setCorrupted
```
protected final void setCorrupted(boolean c)
```
    Set a boolean value which determines whether this packet is corrupted or not.
    
    Parameters:
    
    c - true indicates that this packet is corrupted.
  - getRawPayloadSize
```
protected final int getRawPayloadSize()
```
    Return the size of the raw payload in this packet.
    
    Returns:
    
    The number of bytes in the raw payload.
  - getFieldOffset
```
protected int getFieldOffset(String name,
                             Packet.HeaderField entry)
```
    Return the offset of the header field configured in the given instance.
    
    Parameters:
    
    name - The name of the header field.
    
    entry - The header field entry associated with name.
    
    Returns:
    
    The offset of the requested field.
  - getFieldNumBits
```
protected int getFieldNumBits(String name,
                              Packet.HeaderField entry)
```
    Return the number of bits in the header field configured in the given instance.
    
    Parameters:
    
    name - The name of the header field.
    
    entry - The header field entry associated with name.
    
    Returns:
    
    The number of bits of the requested field.
  - equalsField
```
protected boolean equalsField(String name,
                              byte[] value1,
                              byte[] value2)
```
    Compare the given header field values.
    
    Parameters:
    
    name - The name of the header field.
    
    value1 - The first header field value to be compared.
    
    value2 - The second header field value to be compared.
    
    Returns:
    
    true only if the given two header field values are identical.
  - getBytes
```
protected final byte[] getBytes(String name)
```
    Return the value of the specified field as a byte array.
    
    Parameters:
    
    name - The name of the field.
    
    Returns:
    
    A byte array.
  - getByte
```
protected final byte getByte(String name)
```
    Return the value of the specified field as a byte.
    
    Parameters:
    
    name - The name of the field.
    
    Returns:
    
    A byte value.
  - getInt
```
protected final int getInt(String name)
```
    Return the value of the specified field as an integer.
    
    Parameters:
    
    name - The name of the field.
    
    Returns:
    
    An integer value.
  - getShort
```
protected final short getShort(String name)
```
    Return the value of the specified field as a short integer.
    
    Parameters:
    
    name - The name of the field.
    
    Returns:
    
    A short integer value.
  - getIp4Network
```
protected final Ip4Network getIp4Network(String name)
```
    Return the value of the specified field as an IPv4 address.
    
    Parameters:
    
    name - The name of the field.
    
    Returns:
    
    An Ip4Network instance.
  - isZeroShort
```
protected final boolean isZeroShort(byte[] value)
```
    Determine whether the given value represents a zero short value or not.
    
    Parameters:
    
    value - A byte array that contains a short integer.
    
    Returns:
    
    true only if the given value represents a zero.
  - getHeaderFormat
```
protected abstract Map<String,Packet.HeaderField> getHeaderFormat()
```
    Return a map that determines the format of the packet.
    
    Returns:
    
    A map that determines the format of the packet.
  - hashCode
```
public final int hashCode()
```
    Return the hash code of this object.
    Note that this method never uses the payload to compute the hash code.
    
    Overrides:
    
    hashCode in class Object
    
    Returns:
    
    The hash code.
  - equals
```
public final boolean equals(Object o)
```
    Determine whether the given object is identical to this object.
    Note that this method never compares the payload encapsulated by the packet.
    
    Overrides:
    
    equals in class Object
    
    Parameters:
    
    o - An object to be compared.
    
    Returns:
    
    true if identical. Otherwise false.
  - toString
```
public final String toString()
```
    Return a string representation of this object.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    A string representation of this object.
  - clone
```
public Packet clone()
```
    Return a deep copy of this packet.
    
    Overrides:
    
    clone in class Object
    
    Returns:
    
    A deep copy of this packet.

Class Packet

Nested Class Summary

Method Summary

Methods inherited from class java.lang.Object

Method Detail

getPayload

setPayload

deserialize

serialize

postSerializeCustomOperation

postDeserializeCustomOperation

setPayloadClass

setHeaderField

getHeaderFieldMap

getHeaderSize

getFieldOffset

getFieldNumBits

getRawPayload

setRawPayload

isCorrupted

setCorrupted

getRawPayloadSize

getFieldOffset

getFieldNumBits

equalsField

getBytes

getByte

getInt

getShort

getIp4Network

isZeroShort

getHeaderFormat

hashCode

equals

toString

clone