SSF.OS.BGP4.Path
Class Segment

java.lang.Object
  |
  +--SSF.OS.BGP4.Path.Segment

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable

public class Segment

extends java.lang.Object

implements java.io.Externalizable

An AS path segment. A path segment is a grouping of ASes (indicated by NHI address prefix) which comprises a portion of an AS path. A segment can either be an unordered set of ASes or an ordered sequence of ASes.

See Also:

Serialized Form

Field Summary

java.util.ArrayList	asnhs The AS NHI prefix addresses which make up this segment of the path.
static int	SEQ Indicates a segment type of AS_SEQUENCE, meaning that the ASes in the segment are ordered.
static int	SET Indicates a segment type of AS_SET, meaning that the ASes in the segment are not ordered.
int	typ The type of the path segment.

Constructor Summary

Segment()
Empty constructor.

Segment(int ty, java.util.ArrayList asn)
Generic constructor for initializing member data.

Segment(Segment seg)
Constructs a path segment based on another one.

Method Summary

void	append_as(java.lang.String asnh) Adds an AS NHI prefix address to the end of the list.
boolean	contains(java.lang.String asnh) Determines whether or not this path segment contains a given AS.
boolean	equals(Segment seg) Returns true only if the two path segments are equivalent.
void	prepend_as(java.lang.String asnh) Adds an AS NHI prefix address to the beginning of the list.
void	readExternal(java.io.DataInput in) Reads the contents of this object from a serialization stream.
void	readExternal(java.io.ObjectInput in)
int	size() Returns the number of ASes in this path segment.
java.lang.String	toMinString() Returns this path segment as a string, leaving out set/sequence info.
java.lang.String	toMinString(char sepchar, boolean usenhi) Returns this path segment as a string, leaving out set/sequence info.
java.lang.String	toString() Returns this path segment as a string.
void	writeExternal(java.io.DataOutput out) Writes the contents of this object to a serialization stream.
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class java.lang.Object

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

Field Detail

SET

public static final int SET

Indicates a segment type of AS_SET, meaning that the ASes in the segment are not ordered.

See Also:

Constant Field Values

SEQ

public static final int SEQ

Indicates a segment type of AS_SEQUENCE, meaning that the ASes in the segment are ordered. Those closer to the beginning of the list (lower indices) have been added more recently.

See Also:

Constant Field Values

typ

public int typ

The type of the path segment. Either an unordered (set) or ordered (sequence) group of ASes.

asnhs

public java.util.ArrayList asnhs

The AS NHI prefix addresses which make up this segment of the path.

Constructor Detail

Segment

public Segment()

Empty constructor. Used to deserialize this object.

Segment

public Segment(int ty,
               java.util.ArrayList asn)

Generic constructor for initializing member data.

Parameters:

ty - The type of the path segment.

asn - The AS NHI prefix addresses making up the path segment.

Segment

public Segment(Segment seg)

Constructs a path segment based on another one.

Method Detail

size

public final int size()

Returns the number of ASes in this path segment.

Returns:

the number of ASes in this path segment

contains

public boolean contains(java.lang.String asnh)

Determines whether or not this path segment contains a given AS.

Parameters:

asnh - The NHI prefix of the AS to look for in this segment.

Returns:

true only if the AS is in this segment

prepend_as

public final void prepend_as(java.lang.String asnh)

Adds an AS NHI prefix address to the beginning of the list.

append_as

public final void append_as(java.lang.String asnh)

Adds an AS NHI prefix address to the end of the list.

Parameters:

asnh - The AS NHI prefix address to append to this segment.

equals

public boolean equals(Segment seg)

Returns true only if the two path segments are equivalent. This means that if it is a sequence, the AS NHI prefix addresses must be in the same order, but if it is a set, they need not be in the same order.

Parameters:

seg - The path segment to compare with this one.

Returns:

true if either of two cases holds: (1) the segments are both sequences and have identical lists of AS NHI prefix addresses or (2) the segments are both sets and contain exactly the same AS NHI prefix addresses, not necessarily in the same order

toMinString

public final java.lang.String toMinString(char sepchar,
                                          boolean usenhi)

Returns this path segment as a string, leaving out set/sequence info.

Parameters:

sepchar - The character used to separate ASes in the string.

usenhi - Whether to show ASes as NHI address prefixes or numbers

Returns:

the path segment as a string of ASes

toMinString

public final java.lang.String toMinString()

Returns this path segment as a string, leaving out set/sequence info.

Returns:

the path segment as a string of ASes

toString

public final java.lang.String toString()

Returns this path segment as a string.

Overrides:

toString in class java.lang.Object

Returns:

the path segment as a string

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Specified by:

writeExternal in interface java.io.Externalizable

java.io.IOException

writeExternal

public void writeExternal(java.io.DataOutput out)
                   throws java.io.IOException

Writes the contents of this object to a serialization stream.

Throws:

java.io.IOException - if there's an error writing the data

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Specified by:

readExternal in interface java.io.Externalizable

java.io.IOException

java.lang.ClassNotFoundException

readExternal

public void readExternal(java.io.DataInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Reads the contents of this object from a serialization stream.

Throws:

java.io.IOException - if there's an error reading in the data

java.lang.ClassNotFoundException - if a class name is unrecognized