edu.unika.aifb.rdf.crawler
Class ChannelPool

java.lang.Object
  |
  +--edu.unika.aifb.rdf.crawler.ChannelPool

public class ChannelPool

extends java.lang.Object

This class gets URIs one by one and decides when to start new threads. It maintains a static reference to URIList and SetModel, so that the threads (also known as Channels) can update the status of this list and the accumulating RDF model

Field Summary

static java.util.Vector	bigvect
Cache	cache
static int	capacity
static java.lang.StringBuffer	finishedthreads
static URIList	urilist

Constructor Summary

ChannelPool(URIList urilist, Cache cache, int capacity, int deadline)
This constructor initializes ChannelPool - normally there is just one instance of it per program.

Method Summary

static boolean

getEndSignal()

Methods inherited from class java.lang.Object

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

Field Detail

capacity

public static int capacity

finishedthreads

public static java.lang.StringBuffer finishedthreads

urilist

public static URIList urilist

bigvect

public static java.util.Vector bigvect

cache

public Cache cache

Constructor Detail

ChannelPool

public ChannelPool(URIList urilist,
                   Cache cache,
                   int capacity,
                   int deadline)

This constructor initializes ChannelPool - normally there is just one instance of it per program. It stores a static reference to the URIList, the list may be updated by requests from ChannelPool or individual channels therein.

Also static reference of the cache.

We pass also capacity constraint - no more channels than "capacity" should be created for optimum performance. "deadline" - for how many seconds we are performing operations in the network (networking is assumed to be the bottleneck). After deadline no more new threads are created, but the existing ones may be allowed to finish their document processing.

Method Detail

getEndSignal

public static boolean getEndSignal()