// NoticedURL.java
// -----------------------
// part of YaCy
// (C) by Michael Peter Christen; mc@yacy.net
// first published on http://www.anomic.de
// Frankfurt, Germany, 2004
//
//$LastChangedDate$
//$LastChangedRevision$
//$LastChangedBy$
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
// NURL - noticed (known but not loaded) URL's
package de.anomic.crawler;
import java.io.File;
import java.io.IOException;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import net.yacy.kelondro.index.HandleSet;
import net.yacy.kelondro.index.RowSpaceExceededException;
import net.yacy.kelondro.logging.Log;
import net.yacy.kelondro.order.Base64Order;
import de.anomic.crawler.retrieval.Request;
public class NoticedURL {
public enum StackType {
NULL, CORE, LIMIT, OVERHANG, REMOTE, NOLOAD, IMAGE, MOVIE, MUSIC;
}
public static final long minimumLocalDeltaInit = 10; // the minimum time difference between access of the same local domain
public static final long minimumGlobalDeltaInit = 500; // the minimum time difference between access of the same global domain
private Balancer coreStack; // links found by crawling to depth-1
private Balancer limitStack; // links found by crawling at target depth
private Balancer remoteStack; // links from remote crawl orders
private Balancer noloadStack; // links that are not passed to a loader; the index will be generated from the Request entry
public NoticedURL(
final File cachePath,
final Set<String> myAgentIDs,
final boolean useTailCache,
final boolean exceed134217727) {
Log.logInfo("NoticedURL", "CREATING STACKS at " + cachePath.toString());
this.coreStack = new Balancer(cachePath, "urlNoticeCoreStack", minimumLocalDeltaInit, minimumGlobalDeltaInit, myAgentIDs, useTailCache, exceed134217727);
this.limitStack = new Balancer(cachePath, "urlNoticeLimitStack", minimumLocalDeltaInit, minimumGlobalDeltaInit, myAgentIDs, useTailCache, exceed134217727);
//overhangStack = new plasmaCrawlBalancer(overhangStackFile);
this.remoteStack = new Balancer(cachePath, "urlNoticeRemoteStack", minimumLocalDeltaInit, minimumGlobalDeltaInit, myAgentIDs, useTailCache, exceed134217727);
this.noloadStack = new Balancer(cachePath, "urlNoticeNoLoadStack", minimumLocalDeltaInit, minimumGlobalDeltaInit, myAgentIDs, useTailCache, exceed134217727);
}
public long getMinimumLocalDelta() {
return this.coreStack.getMinimumLocalDelta();
}
public long getMinimumGlobalDelta() {
return this.coreStack.getMinimumGlobalDelta();
}
public void setMinimumDelta(final long minimumLocalDelta, final long minimumGlobalDelta) {
this.coreStack.setMinimumDelta(minimumLocalDelta, minimumGlobalDelta);
this.limitStack.setMinimumDelta(minimumLocalDelta, minimumGlobalDelta);
this.remoteStack.setMinimumDelta(minimumLocalDelta, minimumGlobalDelta);
this.noloadStack.setMinimumDelta(minimumLocalDelta, minimumGlobalDelta);
}
public void clear() {
Log.logInfo("NoticedURL", "CLEARING ALL STACKS");
this.coreStack.clear();
this.limitStack.clear();
this.remoteStack.clear();
this.noloadStack.clear();
}
public void close() {
Log.logInfo("NoticedURL", "CLOSING ALL STACKS");
if (this.coreStack != null) {
this.coreStack.close();
this.coreStack = null;
}
if (this.limitStack != null) {
this.limitStack.close();
this.limitStack = null;
}
//overhangStack.close();
if (this.remoteStack != null) {
this.remoteStack.close();
this.remoteStack = null;
}
if (this.noloadStack != null) {
this.noloadStack.close();
this.noloadStack = null;
}
}
@Override
protected void finalize() throws Throwable {
if ((this.coreStack != null) || (this.limitStack != null) || (this.remoteStack != null)) {
Log.logWarning("plasmaCrawlNURL", "NURL stack closed by finalizer");
close();
}
super.finalize();
}
public boolean notEmpty() {
return this.coreStack.notEmpty() || this.limitStack.notEmpty() || this.remoteStack.notEmpty() || this.noloadStack.notEmpty();
}
public boolean notEmptyLocal() {
return this.coreStack.notEmpty() || this.limitStack.notEmpty() || this.noloadStack.notEmpty();
}
public int size() {
// this does not count the overhang stack size
return ((this.coreStack == null) ? 0 : this.coreStack.size()) + ((this.limitStack == null) ? 0 : this.limitStack.size()) + ((this.remoteStack == null) ? 0 : this.remoteStack.size());
}
public boolean isEmpty() {
if (this.coreStack == null) return true;
if (!this.coreStack.isEmpty()) return false;
if (!this.limitStack.isEmpty()) return false;
if (!this.remoteStack.isEmpty()) return false;
if (!this.noloadStack.isEmpty()) return false;
return true;
}
public int stackSize(final StackType stackType) {
switch (stackType) {
case NOLOAD: return (this.noloadStack == null) ? 0 : this.noloadStack.size();
case CORE: return (this.coreStack == null) ? 0 : this.coreStack.size();
case LIMIT: return (this.limitStack == null) ? 0 : this.limitStack.size();
case OVERHANG: return 0;
case REMOTE: return (this.remoteStack == null) ? 0 : this.remoteStack.size();
default: return -1;
}
}
public boolean existsInStack(final byte[] urlhashb) {
return
this.coreStack.has(urlhashb) ||
this.limitStack.has(urlhashb) ||
//overhangStack.has(urlhashb) ||
this.remoteStack.has(urlhashb) ||
this.noloadStack.has(urlhashb);
}
/**
* push a crawl request on one of the different crawl stacks
* @param stackType
* @param entry
* @return null if this was successful or a String explaining what went wrong in case of an error
*/
public String push(final StackType stackType, final Request entry) {
try {
switch (stackType) {
case CORE:
return this.coreStack.push(entry);
case LIMIT:
return this.limitStack.push(entry);
case REMOTE:
return this.remoteStack.push(entry);
case NOLOAD:
return this.noloadStack.push(entry);
default:
return "stack type unknown";
}
} catch (final Exception er) {
Log.logException(er);
return "error pushing onto the crawl stack: " + er.getMessage();
}
}
public Request get(final byte[] urlhash) {
Request entry = null;
try {if ((entry = this.noloadStack.get(urlhash)) != null) return entry;} catch (final IOException e) {}
try {if ((entry = this.coreStack.get(urlhash)) != null) return entry;} catch (final IOException e) {}
try {if ((entry = this.limitStack.get(urlhash)) != null) return entry;} catch (final IOException e) {}
try {if ((entry = this.remoteStack.get(urlhash)) != null) return entry;} catch (final IOException e) {}
return null;
}
/**
* remove a CrawlEntry by a given hash. Usage of this method is not encouraged,
* because the underlying data structure (crawl stacks) cannot handle removals very good.
* @param urlhash
* @return true, if the entry was removed; false if not
*/
public boolean removeByURLHash(final byte[] urlhashBytes) {
try {
final HandleSet urlHashes = new HandleSet(12, Base64Order.enhancedCoder, 1);
urlHashes.put(urlhashBytes);
boolean ret = false;
try {ret |= this.noloadStack.remove(urlHashes) > 0;} catch (final IOException e) {}
try {ret |= this.coreStack.remove(urlHashes) > 0;} catch (final IOException e) {}
try {ret |= this.limitStack.remove(urlHashes) > 0;} catch (final IOException e) {}
try {ret |= this.remoteStack.remove(urlHashes) > 0;} catch (final IOException e) {}
return ret;
} catch (final RowSpaceExceededException e) {
Log.logException(e);
return false;
}
}
public int removeByProfileHandle(final String handle, final long timeout) throws RowSpaceExceededException {
int removed = 0;
try {removed += this.noloadStack.removeAllByProfileHandle(handle, timeout);} catch (final IOException e) {}
try {removed += this.coreStack.removeAllByProfileHandle(handle, timeout);} catch (final IOException e) {}
try {removed += this.limitStack.removeAllByProfileHandle(handle, timeout);} catch (final IOException e) {}
try {removed += this.remoteStack.removeAllByProfileHandle(handle, timeout);} catch (final IOException e) {}
return removed;
}
public List<Request> top(final StackType stackType, final int count) {
switch (stackType) {
case CORE: return top(this.coreStack, count);
case LIMIT: return top(this.limitStack, count);
case REMOTE: return top(this.remoteStack, count);
case NOLOAD: return top(this.noloadStack, count);
default: return null;
}
}
public Request pop(final StackType stackType, final boolean delay, final CrawlSwitchboard cs) throws IOException {
switch (stackType) {
case CORE: return pop(this.coreStack, delay, cs);
case LIMIT: return pop(this.limitStack, delay, cs);
case REMOTE: return pop(this.remoteStack, delay, cs);
case NOLOAD: return pop(this.noloadStack, false, cs);
default: return null;
}
}
public void shift(final StackType fromStack, final StackType toStack, final CrawlSwitchboard cs) {
try {
final Request entry = pop(fromStack, false, cs);
if (entry != null) {
final String warning = push(toStack, entry);
if (warning != null) {
Log.logWarning("NoticedURL", "shift from " + fromStack + " to " + toStack + ": " + warning);
}
}
} catch (final IOException e) {
return;
}
}
public void clear(final StackType stackType) {
Log.logInfo("NoticedURL", "CLEARING STACK " + stackType);
switch (stackType) {
case CORE: this.coreStack.clear(); break;
case LIMIT: this.limitStack.clear(); break;
case REMOTE: this.remoteStack.clear(); break;
case NOLOAD: this.noloadStack.clear(); break;
default: return;
}
}
private Request pop(final Balancer balancer, final boolean delay, final CrawlSwitchboard cs) throws IOException {
// this is a filo - pop
int s;
Request entry;
int errors = 0;
synchronized (balancer) {
while ((s = balancer.size()) > 0) {
entry = balancer.pop(delay, cs);
if (entry == null) {
if (s > balancer.size()) continue;
errors++;
if (errors < 100) continue;
final int aftersize = balancer.size();
balancer.clear(); // the balancer is broken and cannot shrink
Log.logWarning("BALANCER", "entry is null, balancer cannot shrink (bevore pop = " + s + ", after pop = " + aftersize + "); reset of balancer");
}
return entry;
}
}
return null;
}
private List<Request> top(final Balancer balancer, int count) {
// this is a filo - top
if (count > balancer.size()) count = balancer.size();
return balancer.top(count);
}
public Iterator<Request> iterator(final StackType stackType) {
// returns an iterator of plasmaCrawlBalancerEntry Objects
try {switch (stackType) {
case CORE: return this.coreStack.iterator();
case LIMIT: return this.limitStack.iterator();
case REMOTE: return this.remoteStack.iterator();
case NOLOAD: return this.noloadStack.iterator();
default: return null;
}} catch (final IOException e) {
return new HashSet<Request>().iterator();
}
}
}