// WebStructureGraph.java
// -----------------------------
// (C) 2007 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 15.05.2007 on http://yacy.net
//
// This is a part of YaCy, a peer-to-peer based web search engine
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// LICENSE
//
// 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
package net.yacy.peers.graphics;
import java.io.File;
import java.io.Serializable;
import java.text.ParseException;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import net.yacy.cora.date.GenericFormatter;
import net.yacy.cora.date.MicroDate;
import net.yacy.cora.document.encoding.ASCII;
import net.yacy.cora.document.encoding.UTF8;
import net.yacy.cora.document.id.AnchorURL;
import net.yacy.cora.document.id.DigestURL;
import net.yacy.cora.order.Base64Order;
import net.yacy.cora.sorting.ClusteredScoreMap;
import net.yacy.cora.sorting.ReversibleScoreMap;
import net.yacy.cora.util.ConcurrentLog;
import net.yacy.cora.util.LookAheadIterator;
import net.yacy.cora.util.SpaceExceededException;
import net.yacy.document.Document;
import net.yacy.kelondro.index.Row;
import net.yacy.kelondro.index.Row.Entry;
import net.yacy.kelondro.rwi.AbstractReference;
import net.yacy.kelondro.rwi.Reference;
import net.yacy.kelondro.rwi.ReferenceContainer;
import net.yacy.kelondro.rwi.ReferenceContainerCache;
import net.yacy.kelondro.rwi.ReferenceFactory;
import net.yacy.kelondro.util.FileUtils;
import net.yacy.search.Switchboard;
/**
* Holds lists of links per host names to allow reconstructing a web graph structure of links.
*/
public class WebStructureGraph {
/** Maximum number of references per host, to avoid overflow when a large link farm occurs (i.e. wikipedia) */
public static final int maxref = 200;
/** Maximum number of hosts in web structure map */
public static final int maxhosts = 10000;
/** Maximum number of parsed anchors when computing the structure of a newly added document */
public static final int MAX_PARSED_ANCHORS = 1000;
private final static ConcurrentLog log = new ConcurrentLog("WebStructureGraph");
/** Eventual backup file */
private final File structureFile;
/**
* <p>Older structure entries (notably loaded from the backup file).</p>
* <p>Maps from two parts concatenated string keys to byte array encoded references lists :
* "'b64hash(6)','hostname" to 'date-yyyymmdd(8)'{'target-b64hash(6)''target-count-hex(4)'}*</p>
* */
private final TreeMap<String, byte[]> structure_old;
/**
* <p>Recently computed structure entries</p>
* <p>Maps from two parts concatenated string keys to byte array encoded references lists :
* "'b64hash(6)','hostname" to 'date-yyyymmdd(8)'{'target-b64hash(6)''target-count-hex(4)'}*</p>
* */
private final TreeMap<String, byte[]> structure_new;
/** Queue used to receive new entries to store */
private final BlockingQueue<LearnObject> publicRefDNSResolvingQueue;
/** Worker thread consuming the publicRefDNSResolvingQueue */
private final PublicRefDNSResolvingProcess publicRefDNSResolvingWorker;
/** Entry used to terminate the worker thread */
private final static LearnObject leanrefObjectPOISON = new LearnObject(null, null);
/**
* Used to feed a new entry to this web structure
*/
protected static class LearnObject {
/** Source URL */
private final DigestURL url;
/** Target link URLs */
private final Set<DigestURL> globalRefURLs;
protected LearnObject(final DigestURL url, final Set<DigestURL> globalRefURLs) {
this.url = url;
this.globalRefURLs = globalRefURLs;
}
}
/**
* Constructs an instance, eventually loads entries from the supplied backup
* structureFile when it exists and starts the worker thread.
*
* @param structureFile
* backup file
*/
public WebStructureGraph(final File structureFile) {
this.structure_old = new TreeMap<String, byte[]>();
this.structure_new = new TreeMap<String, byte[]>();
this.structureFile = structureFile;
this.publicRefDNSResolvingQueue = new LinkedBlockingQueue<LearnObject>();
// load web structure from file if exists
Map<String, byte[]> loadedStructureB;
try {
if(this.structureFile != null && this.structureFile.exists()) {
loadedStructureB = FileUtils.loadMapB(this.structureFile);
log.info("loaded dump of " + loadedStructureB.size() + " entries from " + this.structureFile.toString());
} else {
loadedStructureB = new TreeMap<String, byte[]>();
}
} catch (final OutOfMemoryError e ) {
loadedStructureB = new TreeMap<String, byte[]>();
}
this.structure_old.putAll(loadedStructureB);
// delete out-dated entries in case the structure is too big
if ( this.structure_old.size() > maxhosts ) {
// fill a set with last-modified - dates of the structure
final TreeSet<String> delset = new TreeSet<String>();
String key;
byte[] value;
for ( final Map.Entry<String, byte[]> entry : this.structure_old.entrySet() ) {
key = entry.getKey();
value = entry.getValue();
if ( value != null && value.length >= 8 ) {
delset.add(UTF8.String(value).substring(0, 8) + key);
}
}
int delcount = this.structure_old.size() - (maxhosts * 9 / 10);
final Iterator<String> j = delset.iterator();
while ( (delcount > 0) && (j.hasNext()) ) {
this.structure_old.remove(j.next().substring(8));
delcount--;
}
}
this.publicRefDNSResolvingWorker = new PublicRefDNSResolvingProcess();
this.publicRefDNSResolvingWorker.start();
}
/**
* Task consuming the queue of new entries to compute and add to the structure
*/
private class PublicRefDNSResolvingProcess extends Thread {
private PublicRefDNSResolvingProcess() {
this.setName("WebStructureGraph.PublicRefDNSResolvingProcess");
}
@Override
public void run() {
LearnObject lro;
try {
while ( (lro = WebStructureGraph.this.publicRefDNSResolvingQueue.take()) != leanrefObjectPOISON ) {
learnrefs(lro);
}
} catch (final InterruptedException e ) {
}
}
}
/**
* Clear the complete web structure.
*/
public void clear() {
this.structure_old.clear();
this.structure_new.clear();
}
public void generateCitationReference(final DigestURL url, final Document document) {
// generate citation reference
final Map<AnchorURL, String> hl = document.getHyperlinks();
final Iterator<AnchorURL> it = hl.keySet().iterator();
final HashSet<DigestURL> globalRefURLs = new HashSet<DigestURL>();
final String refhost = url.getHost();
DigestURL u;
int maxref = MAX_PARSED_ANCHORS;
while ( it.hasNext() && maxref-- > 0 ) {
u = it.next();
if ( u == null ) {
continue;
}
if ( refhost != null && u.getHost() != null && !u.getHost().equals(refhost) ) {
// this is a global link
globalRefURLs.add(u);
}
}
final LearnObject lro = new LearnObject(url, globalRefURLs);
if (!globalRefURLs.isEmpty()) {
try {
if (this.publicRefDNSResolvingWorker.isAlive()) {
this.publicRefDNSResolvingQueue.put(lro);
} else {
learnrefs(lro);
}
} catch (final InterruptedException e ) {
learnrefs(lro);
}
}
}
public void generateCitationReference(final DigestURL from, final DigestURL to) {
final HashSet<DigestURL> globalRefURLs = new HashSet<DigestURL>();
final String refhost = from.getHost();
if (refhost != null && to.getHost() != null && !to.getHost().equals(refhost)) globalRefURLs.add(to);
final LearnObject lro = new LearnObject(from, globalRefURLs);
if ( !globalRefURLs.isEmpty() ) {
try {
if (this.publicRefDNSResolvingWorker.isAlive()) {
this.publicRefDNSResolvingQueue.put(lro);
} else {
learnrefs(lro);
}
} catch (final InterruptedException e ) {
learnrefs(lro);
}
}
}
/**
* @param refs references information serialized in a string
* @return the decoded references map size
*/
private static int refstr2count(final String refs) {
if (refs == null || refs.length() <= 8) return 0;
assert (refs.length() - 8) % 10 == 0 : "refs = " + refs + ", length = " + refs.length();
return (refs.length() - 8) / 10;
}
/**
* @param refs references information serialized in a string
* @return the decoded references mapping from host hashes to counts
*/
private static Map<String, Integer> refstr2map(final String refs) {
if (refs == null || refs.length() <= 8) return new HashMap<String, Integer>();
final Map<String, Integer> map = new HashMap<String, Integer>();
String c;
final int refsc = refstr2count(refs);
int d;
for (int i = 0; i < refsc; i++) {
c = refs.substring(8 + i * 10, 8 + (i + 1) * 10);
try {
d = Integer.valueOf(c.substring(6), 16);
} catch (final NumberFormatException e ) {
d = 1;
}
map.put(c.substring(0, 6), d);
}
return map;
}
/**
* @return an empty references map serialized to a string
*/
private static String none2refstr() {
return GenericFormatter.SHORT_DAY_FORMATTER.format();
}
/**
* @param map references mapping from host hashes to counts
* @return the map serialized as a string
*/
private static String map2refstr(final Map<String, Integer> map) {
final StringBuilder s = new StringBuilder(GenericFormatter.PATTERN_SHORT_DAY.length() + map.size() * 10);
s.append(GenericFormatter.SHORT_DAY_FORMATTER.format());
String h;
for ( final Map.Entry<String, Integer> entry : map.entrySet() ) {
s.append(entry.getKey());
h = Integer.toHexString(entry.getValue().intValue());
final int hl = h.length();
if ( hl == 0 ) {
s.append("0000");
} else if ( hl == 1 ) {
s.append("000").append(h);
} else if ( hl == 2 ) {
s.append("00").append(h);
} else if ( hl == 3 ) {
s.append('0').append(h);
} else if ( hl == 4 ) {
s.append(h);
} else {
s.append("FFFF");
}
}
return s.toString();
}
/**
* @param hosthash host hash
* @return true when this host hash is present in this web structure (either in latest or elder known entries)
*/
public boolean exists(final String hosthash) {
// returns a map with a hosthash(String):refcount(Integer) relation
assert hosthash.length() == 6;
SortedMap<String, byte[]> tailMap;
synchronized ( this.structure_old ) {
tailMap = this.structure_old.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
return true;
}
}
}
synchronized ( this.structure_new ) {
tailMap = this.structure_new.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
return true;
}
}
}
return false;
}
/**
* Compute outgoing references from the source host hash
* @param srcHostName reference source host hash
* @return outgoing structure with references mapped from target host hashes to counts or null when the host is not known
*/
public StructureEntry outgoingReferences(final String hosthash) {
// returns a map with a hosthash(String):refcount(Integer) relation
assert hosthash.length() == 6;
SortedMap<String, byte[]> tailMap;
Map<String, Integer> h = new HashMap<String, Integer>();
String hostname = "";
String date = "";
String ref;
synchronized ( this.structure_old ) {
tailMap = this.structure_old.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
hostname = key.substring(7);
ref = ASCII.String(tailMap.get(key));
date = ref.substring(0, 8);
h = refstr2map(ref);
}
}
}
synchronized ( this.structure_new ) {
tailMap = this.structure_new.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
ref = ASCII.String(tailMap.get(key));
if ( hostname.isEmpty() ) {
hostname = key.substring(7);
}
if ( date.isEmpty() ) {
date = ref.substring(0, 8);
}
h.putAll(refstr2map(ref));
}
}
}
if (h.isEmpty()) return null;
return new StructureEntry(hosthash, hostname, date, h);
}
/**
* Compute outgoing references from the source hostName on any source protocol or port.
* @param srcHostName reference source host name
* @return outgoing references mapped from target host hashes to counts. Can be empty when the host name is not known.
*/
public Map<String, Integer> outgoingReferencesByHostName(final String srcHostName) {
Set<String> srcHostHashes = this.hostName2HostHashes(srcHostName);
final Map<String, Integer> targetHashesToCount = new HashMap<String, Integer>();
for(String srcHostHash : srcHostHashes) {
final WebStructureGraph.StructureEntry sr = this.outgoingReferences(srcHostHash);
if(sr != null) {
for(java.util.Map.Entry<String, Integer> ref : sr.references.entrySet()) {
Integer refsNb = targetHashesToCount.get(ref.getKey());
if(refsNb != null) {
if(ref.getValue() != null) {
refsNb += ref.getValue();
}
} else {
if(ref.getValue() != null) {
refsNb = ref.getValue();
} else {
refsNb = Integer.valueOf(0);
}
}
targetHashesToCount.put(ref.getKey(), refsNb);
}
}
}
return targetHashesToCount;
}
/**
* Compute incoming references to the target host hash
* @param hosthash reference target host hash
* @return incoming structure with references mapped from source host hashes to counts or null when the target is not known
*/
public StructureEntry incomingReferences(final String hosthash) {
final String hostname = hostHash2hostName(hosthash);
if ( hostname == null ) {
return null;
}
// collect the references
WebStructureGraph.StructureEntry sentry;
final HashMap<String, Integer> hosthashes = new HashMap<String, Integer>();
Iterator<WebStructureGraph.StructureEntry> i = new StructureIterator(false);
while ( i.hasNext() ) {
sentry = i.next();
if ( sentry.references.containsKey(hosthash) ) {
hosthashes.put(sentry.hosthash, sentry.references.get(hosthash));
}
}
i = new StructureIterator(true);
while ( i.hasNext() ) {
sentry = i.next();
if ( sentry.references.containsKey(hosthash) ) {
hosthashes.put(sentry.hosthash, sentry.references.get(hosthash));
}
}
// construct a new structureEntry Object
return new StructureEntry(
hosthash,
hostname,
GenericFormatter.SHORT_DAY_FORMATTER.format(),
hosthashes);
}
public static class HostReferenceFactory implements ReferenceFactory<HostReference>, Serializable {
private static final long serialVersionUID=7461135579006223155L;
private static final Row hostReferenceRow = new Row(
"String h-6, Cardinal m-4 {b256}, Cardinal c-4 {b256}",
Base64Order.enhancedCoder);
public HostReferenceFactory() {
}
@Override
public Row getRow() {
return hostReferenceRow;
}
@Override
public HostReference produceSlow(final Entry e) {
return new HostReference(e);
}
@Override
public HostReference produceFast(final HostReference e, final boolean local) {
return e;
}
}
public static class HostReference extends AbstractReference implements Reference, Serializable {
private static final long serialVersionUID=-9170091435821206765L;
private final Row.Entry entry;
private HostReference(final byte[] hostHash, final long modified, final int count) {
assert (hostHash.length == 6) : "hostHash = " + ASCII.String(hostHash);
this.entry = hostReferenceFactory.getRow().newEntry();
this.entry.setCol(0, hostHash);
this.entry.setCol(1, MicroDate.microDateDays(modified));
this.entry.setCol(2, count);
}
public HostReference(final String json) {
this.entry = hostReferenceFactory.getRow().newEntry(json, true);
}
private HostReference(final Row.Entry entry) {
this.entry = entry;
}
@Override
public String toPropertyForm() {
return this.entry.toPropertyForm(':', true, true, false, true);
}
@Override
public Entry toKelondroEntry() {
return this.entry;
}
@Override
public byte[] urlhash() {
return this.entry.getPrimaryKeyBytes();
}
private int count() {
return (int) this.entry.getColLong(2);
}
@Override
public long lastModified() {
return MicroDate.reverseMicroDateDays((int) this.entry.getColLong(1));
}
@Override
public void join(final Reference r) {
// joins two entries into one entry
final HostReference oe = (HostReference) r;
// combine date
final long o = oe.lastModified();
if ( lastModified() < o ) {
this.entry.setCol(1, MicroDate.microDateDays(o));
}
// combine count
final int c = oe.count();
if ( count() < c ) {
this.entry.setCol(2, c);
}
}
@Override
public Collection<Integer> positions() {
return null;
}
@Override
public int posintext() {
throw new UnsupportedOperationException();
}
}
public static final HostReferenceFactory hostReferenceFactory = new HostReferenceFactory();
private static ReferenceContainerCache<HostReference> hostReferenceIndexCache = null;
private static long hostReferenceIndexCacheTime = 0;
private static final long hostReferenceIndexCacheTTL = 1000 * 60 * 60 * 12; // 12 hours time to live for cache
public synchronized ReferenceContainerCache<HostReference> incomingReferences() {
// we return a cache if the cache is filled and not stale
if ( hostReferenceIndexCache != null
&& hostReferenceIndexCacheTime + hostReferenceIndexCacheTTL > System.currentTimeMillis() ) {
return hostReferenceIndexCache;
}
// collect the references
final ReferenceContainerCache<HostReference> idx =
new ReferenceContainerCache<HostReference>(hostReferenceFactory, Base64Order.enhancedCoder, 6);
// we iterate over all structure entries.
// one structure entry has information that a specific host links to a list of other hosts
incomingReferencesEnrich(idx, new StructureIterator(false), 3000);
incomingReferencesEnrich(idx, new StructureIterator(true), 3000);
// fill the cache again and set fill time
hostReferenceIndexCache = idx;
hostReferenceIndexCacheTime = System.currentTimeMillis();
//incomingReferencesTest(hostReferenceIndexCache);
return hostReferenceIndexCache;
}
private void incomingReferencesEnrich(
final ReferenceContainerCache<HostReference> idx,
final Iterator<WebStructureGraph.StructureEntry> structureIterator,
final long time) {
// we iterate over all structure entries.
// one structure entry has information that a specific host links to a list of other hosts
final long timeout = time == Long.MAX_VALUE ? Long.MAX_VALUE : System.currentTimeMillis() + time;
byte[] term;
HostReference hr;
WebStructureGraph.StructureEntry sentry;
structureLoop: while ( structureIterator.hasNext() ) {
sentry = structureIterator.next();
// then we loop over all the hosts that are linked from sentry.hosthash
refloop: for ( final Map.Entry<String, Integer> refhosthashandcounter : sentry.references
.entrySet() ) {
term = UTF8.getBytes(refhosthashandcounter.getKey());
try {
hr =
new HostReference(
ASCII.getBytes(sentry.hosthash),
GenericFormatter.SHORT_DAY_FORMATTER.parse(sentry.date, 0).getTime().getTime(),
refhosthashandcounter.getValue().intValue());
} catch (final ParseException e ) {
continue refloop;
}
// each term refers to an index entry. look if we already have such an entry
ReferenceContainer<HostReference> r = idx.get(term, null);
try {
if ( r == null ) {
r = new ReferenceContainer<HostReference>(hostReferenceFactory, term);
r.add(hr);
idx.add(r);
} else {
r.put(hr);
}
} catch (final SpaceExceededException e ) {
continue refloop;
}
}
if ( System.currentTimeMillis() > timeout ) {
break structureLoop;
}
}
}
/**
*
* @param hosthash
* @return the number of hosts that are referenced by this hosthash
*/
public int referencesCount(final String hosthash) {
assert hosthash.length() == 6 : "hosthash = " + hosthash;
if (hosthash == null || hosthash.length() != 6) return 0;
SortedMap<String, byte[]> tailMap;
int c = 0;
try {
synchronized ( this.structure_old ) {
tailMap = this.structure_old.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
c = refstr2count(UTF8.String(tailMap.get(key)));
}
}
}
synchronized ( this.structure_new ) {
tailMap = this.structure_new.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
c += refstr2count(UTF8.String(tailMap.get(key)));
}
}
}
} catch (final Throwable t) {
this.clear();
}
return c;
}
/**
* @param hosthash host name hash
* @return the host name corresponding to the given hash or null when the hash is not known
*/
public String hostHash2hostName(final String hosthash) {
// returns the host as string, null if unknown
assert hosthash.length() == 6;
SortedMap<String, byte[]> tailMap;
synchronized ( this.structure_old ) {
tailMap = this.structure_old.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
return key.substring(7);
}
}
}
synchronized ( this.structure_new ) {
tailMap = this.structure_new.tailMap(hosthash);
if ( !tailMap.isEmpty() ) {
final String key = tailMap.firstKey();
if ( key.startsWith(hosthash) ) {
return key.substring(7);
}
}
}
return null;
}
/**
* Look for host hashes corresponding to the given host name. There can be
* multiple host hashes for one host name as the used hash function
* {@link DigestURL#hosthash()} returns a different result for each
* different protocol or port with a same host name.
*
* @param hostName
* host name
* @return the host hashes corresponding to the given host name or an emtpy set when
* the host name is not known
*/
public Set<String> hostName2HostHashes(final String hostName) {
Set<String> hashes = new HashSet<>();
synchronized (this.structure_old) {
String keyHostName, hash;
for (String key : structure_old.keySet()) {
hash = key.substring(0, 6);
keyHostName = key.substring(7);
if (keyHostName.equalsIgnoreCase(hostName)) {
hashes.add(hash);
}
}
}
synchronized (this.structure_new) {
String keyHostName, hash;
for (String key : structure_new.keySet()) {
hash = key.substring(0, 6);
keyHostName = key.substring(7);
if (keyHostName.equalsIgnoreCase(hostName)) {
hashes.add(hash);
}
}
}
return hashes;
}
protected void learnrefs(final LearnObject lro) {
final DigestURL url = lro.url;
final String sourceHosthash = url.hosthash();
// parse the new reference string and join it with the stored references
final StructureEntry structure = outgoingReferences(sourceHosthash);
final Map<String, Integer> refs = (structure == null) ? new HashMap<String, Integer>() : structure.references;
int c;
for (final DigestURL u : lro.globalRefURLs) {
String domain = u.hosthash();
if (Switchboard.getSwitchboard() != null && Switchboard.getSwitchboard().shallTerminate()) break;
if (!exists(domain)) {
// this must be recorded as an host with no references
synchronized ( this.structure_new ) {
this.structure_new.put(domain + "," + u.getHost(), UTF8.getBytes(none2refstr()));
}
}
c = 0;
Integer existingCount = refs.get(domain);
if ( existingCount != null) {
c = existingCount.intValue();
}
refs.put(domain, Integer.valueOf(++c));
}
// check if the maxref is exceeded
if ( refs.size() > maxref ) {
int shrink = refs.size() - (maxref * 9 / 10);
delloop: while ( shrink > 0 ) {
// shrink the references: the entry with the smallest number of references is removed
int minrefcount = Integer.MAX_VALUE;
String minrefkey = null;
findloop: for ( final Map.Entry<String, Integer> entry : refs.entrySet() ) {
if ( entry.getValue().intValue() < minrefcount ) {
minrefcount = entry.getValue().intValue();
minrefkey = entry.getKey();
}
if ( minrefcount == 1 ) {
break findloop;
}
}
// remove the smallest
if ( minrefkey == null ) {
break delloop;
}
refs.remove(minrefkey);
shrink--;
}
}
// store the map back to the structure
synchronized ( this.structure_new ) {
this.structure_new.put(sourceHosthash + "," + url.getHost(), UTF8.getBytes(map2refstr(refs)));
}
}
private static void joinStructure(final TreeMap<String, byte[]> into, final TreeMap<String, byte[]> from) {
for ( final Map.Entry<String, byte[]> e : from.entrySet() ) {
if ( into.containsKey(e.getKey()) ) {
final Map<String, Integer> s0 = refstr2map(UTF8.String(into.get(e.getKey())));
final Map<String, Integer> s1 = refstr2map(UTF8.String(e.getValue()));
for ( final Map.Entry<String, Integer> r : s1.entrySet() ) {
if ( s0.containsKey(r.getKey()) ) {
s0.put(r.getKey(), s0.get(r.getKey()).intValue() + r.getValue().intValue());
} else {
s0.put(r.getKey(), r.getValue().intValue());
}
}
into.put(e.getKey(), UTF8.getBytes(map2refstr(s0)));
} else {
into.put(e.getKey(), e.getValue());
}
}
}
/**
* Feed the elder entries structure map with latest computed entries map and then clear this last one.
*/
public void joinOldNew() {
synchronized ( this.structure_new ) {
joinStructure(this.structure_old, this.structure_new);
this.structure_new.clear();
}
}
/**
* @return the host name having the most outgoing references or null when the structure is empty
*/
public String hostWithMaxReferences() {
// find host with most references
Map<String, Integer> hostNamesToRefsNb = new TreeMap<>();
int refsize, maxref = 0;
String hostName, maxHostName = null;
Integer refsNb;
synchronized ( this.structure_old ) {
for ( final Map.Entry<String, byte[]> entry : this.structure_old.entrySet() ) {
refsize = entry.getValue().length;
hostName = entry.getKey().substring(7);
refsNb = hostNamesToRefsNb.get(hostName);
if(refsNb == null) {
refsNb = refsize;
} else {
refsNb += refsize;
}
if ( refsNb > maxref ) {
maxref = refsNb;
maxHostName = hostName;
}
hostNamesToRefsNb.put(hostName, refsNb);
}
}
synchronized ( this.structure_new ) {
for ( final Map.Entry<String, byte[]> entry : this.structure_new.entrySet() ) {
refsize = entry.getValue().length;
hostName = entry.getKey().substring(7);
refsNb = hostNamesToRefsNb.get(hostName);
if(refsNb == null) {
refsNb = refsize;
} else {
refsNb += refsize;
}
if ( refsNb > maxref ) {
maxref = refsNb;
maxHostName = hostName;
}
hostNamesToRefsNb.put(hostName, refsNb);
}
}
return maxHostName;
}
public ReversibleScoreMap<String> hostReferenceScore() {
ReversibleScoreMap<String> result = new ClusteredScoreMap<String>(ASCII.identityASCIIComparator);
synchronized ( this.structure_old ) {
for ( final Map.Entry<String, byte[]> entry : this.structure_old.entrySet() ) {
result.set(entry.getKey().substring(7), (entry.getValue().length - 8) / 10);
}
}
synchronized ( this.structure_new ) {
for ( final Map.Entry<String, byte[]> entry : this.structure_new.entrySet() ) {
result.set(entry.getKey().substring(7), (entry.getValue().length - 8) / 10);
}
}
return result;
}
/**
* @param latest <ul>
* <li>true : iterate only the latest computed entries</li>
* <li>false : iterate only the elder computed entries, excluding the latest</li>
* </ul>
* @return an iterator over the web structure
*/
public Iterator<StructureEntry> structureEntryIterator(final boolean latest) {
return new StructureIterator(latest);
}
/**
* Iterator over the web structure
*/
private class StructureIterator extends LookAheadIterator<StructureEntry> implements Iterator<StructureEntry> {
/** Internal iterator instance */
private final Iterator<Map.Entry<String, byte[]>> i;
/**
* @param latest <ul>
* <li>true : iterate only the latest computed entries</li>
* <li>false : iterate only the elder computed entries, excluding the latest</li>
* </ul>
*/
private StructureIterator(final boolean latest) {
this.i = ((latest) ? WebStructureGraph.this.structure_new : WebStructureGraph.this.structure_old).entrySet().iterator();
}
/**
* Iterate to the next structure entry, decoding on the fly the references information from the byte array
*/
@Override
public StructureEntry next0() {
Map.Entry<String, byte[]> entry = null;
String dom = null;
byte[] ref = null;
String refs;
while ( this.i.hasNext() ) {
entry = this.i.next();
ref = entry.getValue();
if ( (ref.length - 8) % 10 != 0 ) {
continue;
}
dom = entry.getKey();
if ( dom.length() >= 8 ) {
break;
}
dom = null;
}
if ( entry == null || dom == null ) {
return null;
}
assert (ref.length - 8) % 10 == 0 : "refs = " + ref + ", length = " + ref.length;
refs = UTF8.String(ref);
return new StructureEntry(
dom.substring(0, 6),
dom.substring(7),
refs.substring(0, 8),
refstr2map(refs));
}
}
public static class StructureEntry implements Comparable<StructureEntry> {
/** 6 bytes host hash */
public String hosthash;
/** the host name */
public String hostname;
/** date of latest change */
public String date;
/** a map from the referenced host hash to the number of references to that host */
public Map<String, Integer> references;
/**
* Create a new empty (no references) entry
* @param hosthash host hash
* @param hostname host name
*/
private StructureEntry(final String hosthash, final String hostname) {
this(hosthash, hostname, GenericFormatter.SHORT_DAY_FORMATTER.format(), new HashMap<String, Integer>());
}
private StructureEntry(
final String hosthash,
final String hostname,
final String date,
final Map<String, Integer> references) {
this.hosthash = hosthash;
this.hostname = hostname;
this.date = date;
this.references = references;
}
@Override
public int compareTo(StructureEntry arg0) {
return hosthash.compareTo(arg0.hosthash);
}
@Override
public boolean equals(Object o) {
if (!(o instanceof StructureEntry)) return false;
return hosthash.equals(((StructureEntry)o).hosthash);
}
@Override
public int hashCode() {
return this.hosthash.hashCode();
}
}
public synchronized void close() {
// finish dns resolving queue
if ( this.publicRefDNSResolvingWorker.isAlive() ) {
log.info("Waiting for the DNS Resolving Queue to terminate");
try {
this.publicRefDNSResolvingQueue.put(leanrefObjectPOISON);
this.publicRefDNSResolvingWorker.join(5000);
} catch (final InterruptedException e ) {
}
}
// save to web structure file
if(this.structureFile != null) {
log.info("Saving Web Structure File: new = "
+ this.structure_new.size()
+ " entries, old = "
+ this.structure_old.size()
+ " entries");
final long time = System.currentTimeMillis();
joinOldNew();
log.info("dumping " + structure_old.size() + " entries to " + structureFile.toString());
if ( !this.structure_old.isEmpty() ) {
synchronized ( this.structure_old ) {
if ( !this.structure_old.isEmpty() ) {
FileUtils
.saveMapB(
this.structureFile,
this.structure_old,
"Web Structure Syntax: <b64hash(6)>','<host> to <date-yyyymmdd(8)>{<target-b64hash(6)><target-count-hex(4)>}*");
final long t = Math.max(1, System.currentTimeMillis() - time);
log.info("Saved Web Structure File: "
+ this.structure_old.size()
+ " entries in "
+ t
+ " milliseconds, "
+ (this.structure_old.size() * 1000 / t)
+ " entries/second");
}
this.structure_old.clear();
}
}
}
}
}