Class BGPReader

java.lang.Object
  |
  +--BGPReader

public class BGPReader

extends java.lang.Object

BGPReader.java Jim Gast, jgast@cs.wisc.edu.

This program extracts all Best Paths from a BGP table (or all of the paths, if you choose not to use bestOnly)

A BGPReader reads lines of a BGP routing file until EOF. The BGP routing file is expected to have:

• # Lines that start with "#" are comments
• * Routings start with "*"
• *> Best routes start with "*>"

The only tricky part is that the destination IP address is not repeated if it is the same as the prior line.

Example:

  24.0.101.0/24    193.0.0.56                             0 3333 1103 6453 1239 6172 ?
                   134.55.24.6                            0 293 1800 1239 6172 ?
>                  144.228.240.93          35             0 1239 6172 ?
  The example shows 3 routes to 24.0.101.0/24.  The third is the "best route".
 

Field Summary

static boolean	ALL_PATHS
static boolean	BEST_ONLY
static java.lang.String	DEFAULT_FILE

Constructor Summary

BGPReader()

BGPReader(boolean bestOnly)

BGPReader(java.lang.String fileName)

BGPReader(java.lang.String fileName, boolean bestOnly)

Method Summary

void	close()
static int	discoverBitLength(java.lang.String str) determine the number of bits in the subnet mask for a given IP address
java.lang.String	discoverDest(java.lang.String str)
java.lang.String	getDest()
java.lang.String	getFileName()
static void	main(java.lang.String[] args) main method is used for testing the class
java.lang.String	readBGPLine()
boolean	ready()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_FILE

public static final java.lang.String DEFAULT_FILE

See Also:

Constant Field Values

BEST_ONLY

public static final boolean BEST_ONLY

See Also:

Constant Field Values

ALL_PATHS

public static final boolean ALL_PATHS

See Also:

Constant Field Values

Constructor Detail

BGPReader

public BGPReader(java.lang.String fileName,
                 boolean bestOnly)

BGPReader

public BGPReader(boolean bestOnly)

BGPReader

public BGPReader(java.lang.String fileName)

BGPReader

public BGPReader()

Method Detail

readBGPLine

public java.lang.String readBGPLine()
                             throws java.io.IOException

java.io.IOException

getDest

public java.lang.String getDest()

ready

public boolean ready()

close

public void close()

getFileName

public java.lang.String getFileName()

discoverDest

public java.lang.String discoverDest(java.lang.String str)

discoverBitLength

public static int discoverBitLength(java.lang.String str)

determine the number of bits in the subnet mask for a given IP address

main

public static void main(java.lang.String[] args)
                 throws java.io.IOException

main method is used for testing the class

java.io.IOException