apps.ping
Class PingCapsule

java.lang.Object
  |
  +--ants.core.Capsule
        |
        +--ants.core.DataCapsule
              |
              +--apps.ping.PingCapsule

public class PingCapsule

extends DataCapsule

Ping capsule.

Author:

David Wetherall, Utah Janos Team

Field Summary

boolean	ping
int	seqId Sequence number for the ping capsule.

Fields inherited from class ants.core.DataCapsule

dpt, spt, VERSION

Fields inherited from class ants.core.Capsule

MAX_TTL

Constructor Summary

PingCapsule()

PingCapsule(short sa, short da, int na, ByteArray d)

Method Summary

Xdr	decode() Decode a capsule header from this Capsule's xdr field.
Xdr	encode() Encode this capsule's header into a new Xdr.
boolean	evaluate(Node n) Forwarding function for DataCapsules.
int	length() Return length of this data capsule.

Methods inherited from class ants.core.DataCapsule

getData, setData, toString

Methods inherited from class ants.core.Capsule

create, encodeCapsuleForSend, findExtension, findMID, findPID, getDst, getPrevious, getSrc, getTTL, prime, setDst

Methods inherited from class java.lang.Object

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

Field Detail

ping

public boolean ping

seqId

public int seqId

Sequence number for the ping capsule.

Constructor Detail

PingCapsule

public PingCapsule()

PingCapsule

public PingCapsule(short sa,
                   short da,
                   int na,
                   ByteArray d)

Method Detail

length

public int length()

Description copied from class: DataCapsule

Return length of this data capsule.

Overrides:

length in class DataCapsule

Tags copied from class: DataCapsule

See Also:

Capsule.length()

encode

public Xdr encode()

Description copied from class: Capsule

Encode this capsule's header into a new Xdr. Return the new Xdr.

Because this header must go first in the Xdr, this encoder unilaterally sets the xdr buffer pointer to the beginning of the buffer and writes its data there.

The format of the Xdr is:

 MethodID         (16 bytes)
 src address      ( 4 bytes)
 dst address      ( 4 bytes)
 previous address ( 4 bytes)
 TTL              ( 4 bytes)
 

Overrides:
encode in class DataCapsule

Tags copied from class: Capsule

Returns:
the new Xdr representing this capsule.
See Also: 
#xdr

decode

public Xdr decode()

Description copied from class: Capsule

Decode a capsule header from this Capsule's xdr field.

Overrides:

decode in class DataCapsule

Tags copied from class: Capsule

Returns:

the new Xdr based on the current xdr.

evaluate

public boolean evaluate(Node n)

Description copied from class: DataCapsule

Forwarding function for DataCapsules. Forwards the capsule to the appropriate application port if the capsule is on its destination node, otherwise forwards the capsule on to its destination node.

Overrides:

evaluate in class DataCapsule

Tags copied from class: Capsule

Parameters:

node - the local node interface

Returns:

an indicationof whether the forwarding was successful.