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b6d9cca67e
yacy_search_server/source/de/anomic/plasma/plasmaSnippetCache.java
orbiter 89e1848db6 fixed problem with favicons: 
target servers had been able to see search words from the referrer of the favicon fetch.
This has been removed by using the getImage - servlet for favicon fetch.
Since java does not support loading of bmp and ico-Images, such parsers had been added.
The image parser had been coded from their original microsoft documentation.
This influences also the image-search functionality: there can now be a preview
of found bmp-images. Another benefit: favicons for search results are now cached with the HTCACHE.

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@3965 6c8d7289-2bf4-0310-a012-ef5d649a1542
2007-07-15 01:34:01 +00:00

896 lines
40 KiB
Java
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// plasmaSnippetCache.java
// -----------------------
// part of YaCy
// (C) by Michael Peter Christen; mc@anomic.de
// first published on http://www.anomic.de
// Frankfurt, Germany, 2005
// last major change: 09.10.2006
//
// contributions by Marc Nause [MN]
//
// 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
//
// Using this software in any meaning (reading, learning, copying, compiling,
// running) means that you agree that the Author(s) is (are) not responsible
// for cost, loss of data or any harm that may be caused directly or indirectly
// by usage of this softare or this documentation. The usage of this software
// is on your own risk. The installation and usage (starting/running) of this
// software may allow other people or application to access your computer and
// any attached devices and is highly dependent on the configuration of the
// software which must be done by the user of the software; the author(s) is
// (are) also not responsible for proper configuration and usage of the
// software, even if provoked by documentation provided together with
// the software.
//
// Any changes to this file according to the GPL as documented in the file
// gpl.txt aside this file in the shipment you received can be done to the
// lines that follows this copyright notice here, but changes must not be
// done inside the copyright notive above. A re-distribution must contain
// the intact and unchanged copyright notice.
// Contributions and changes to the program code must be marked as such.
package de.anomic.plasma;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;
import de.anomic.htmlFilter.htmlFilterImageEntry;
import de.anomic.http.httpHeader;
import de.anomic.http.httpc;
import de.anomic.plasma.plasmaURL;
import de.anomic.kelondro.kelondroMScoreCluster;
import de.anomic.kelondro.kelondroMSetTools;
import de.anomic.net.URL;
import de.anomic.plasma.cache.IResourceInfo;
import de.anomic.plasma.crawler.plasmaCrawlerException;
import de.anomic.plasma.parser.ParserException;
import de.anomic.server.logging.serverLog;
import de.anomic.yacy.yacySearch;
import de.anomic.yacy.yacyCore;
public class plasmaSnippetCache {
private static final int maxCache = 500;
public static final int SOURCE_CACHE = 0;
public static final int SOURCE_FILE = 1;
public static final int SOURCE_WEB = 2;
public static final int ERROR_NO_HASH_GIVEN = 11;
public static final int ERROR_SOURCE_LOADING = 12;
public static final int ERROR_RESOURCE_LOADING = 13;
public static final int ERROR_PARSER_FAILED = 14;
public static final int ERROR_PARSER_NO_LINES = 15;
public static final int ERROR_NO_MATCH = 16;
private int snippetsScoreCounter;
private kelondroMScoreCluster snippetsScore;
private HashMap snippetsCache;
/**
* a cache holding URLs to favicons specified by the page content, e.g. by using the html link-tag. e.g.
* <pre>
* &lt;link rel="shortcut icon" type="image/x-icon" href="../src/favicon.ico"&gt;
* </pre>
*/
private HashMap faviconCache;
private plasmaHTCache cacheManager;
private plasmaParser parser;
private serverLog log;
private plasmaSwitchboard sb;
public plasmaSnippetCache(
plasmaSwitchboard theSb,
plasmaHTCache cacheManager,
plasmaParser parser,
serverLog log
) {
this.cacheManager = cacheManager;
this.parser = parser;
this.log = log;
this.sb = theSb;
this.snippetsScoreCounter = 0;
this.snippetsScore = new kelondroMScoreCluster();
this.snippetsCache = new HashMap();
this.faviconCache = new HashMap();
}
public class TextSnippet {
private URL url;
private String line;
private String error;
private int errorCode;
private Set remaingHashes;
private URL favicon;
public TextSnippet(URL url, String line, int errorCode, Set remaingHashes, String errortext) {
this(url,line,errorCode,remaingHashes,errortext,null);
}
public TextSnippet(URL url, String line, int errorCode, Set remaingHashes, String errortext, URL favicon) {
this.url = url;
this.line = line;
this.errorCode = errorCode;
this.error = errortext;
this.remaingHashes = remaingHashes;
this.favicon = favicon;
}
public URL getUrl() {
return this.url;
}
public boolean exists() {
return line != null;
}
public String toString() {
return (line == null) ? "" : line;
}
public String getLineRaw() {
return (line == null) ? "" : line;
}
public String getError() {
return (error == null) ? "" : error.trim();
}
public int getErrorCode() {
return errorCode;
}
public Set getRemainingHashes() {
return this.remaingHashes;
}
public String getLineMarked(Set queryHashes) {
if (line == null) return "";
if ((queryHashes == null) || (queryHashes.size() == 0)) return line.trim();
if (line.endsWith(".")) line = line.substring(0, line.length() - 1);
Iterator i = queryHashes.iterator();
String h;
String[] w = line.split(" ");
String prefix = "";
String postfix = "";
int len = 0;
while (i.hasNext()) {
h = (String) i.next();
for (int j = 0; j < w.length; j++) {
//ignore punctuation marks (contrib [MN])
//note to myself:
//For details on regex see "Mastering regular expressions" by J.E.F. Friedl
//especially p. 123 and p. 390/391 (in the German version of the 2nd edition)
prefix = "";
postfix = "";
// cut off prefix if it contains of non-characters or non-numbers
while(w[j].matches("\\A[^\\p{L}\\p{N}].+")) {
prefix = prefix + w[j].substring(0,1);
w[j] = w[j].substring(1);
}
// cut off postfix if it contains of non-characters or non-numbers
while(w[j].matches(".+[^\\p{L}\\p{N}]\\Z")) {
len = w[j].length();
postfix = w[j].substring(len-1,len) + postfix;
w[j] = w[j].substring(0,len-1);
}
//special treatment if there is a special character in the word
if(w[j].matches("\\A[\\p{L}\\p{N}]+[^\\p{L}\\p{N}].+\\Z")) {
String out = "";
String temp = "";
for(int k=0; k < w[j].length(); k++) {
//is character a special character?
if(w[j].substring(k,k+1).matches("[^\\p{L}\\p{N}]")) {
if (plasmaCondenser.word2hash(temp).equals(h)) temp = "<b>" + temp + "</b>";
out = out + temp + w[j].substring(k,k+1);
temp = "";
}
//last character
else if(k == (w[j].length()-1)) {
temp = temp + w[j].substring(k,k+1);
if (plasmaCondenser.word2hash(temp).equals(h)) temp = "<b>" + temp + "</b>";
out = out + temp;
temp = "";
}
else temp = temp + w[j].substring(k,k+1);
}
w[j] = out;
}
//end contrib [MN]
else if (plasmaCondenser.word2hash(w[j]).equals(h)) w[j] = "<b>" + w[j] + "</b>";
w[j] = prefix + w[j] + postfix;
}
}
StringBuffer l = new StringBuffer(line.length() + queryHashes.size() * 8);
for (int j = 0; j < w.length; j++) {
l.append(w[j]);
l.append(' ');
}
return l.toString().trim();
}
public URL getFavicon() {
return this.favicon;
}
}
public class MediaSnippet {
public String type, href, name, attr;
public MediaSnippet(String type, String href, String name, String attr) {
this.type = type;
this.href = href;
this.name = name;
this.attr = attr;
if ((this.name == null) || (this.name.length() == 0)) this.name = "_";
if ((this.attr == null) || (this.attr.length() == 0)) this.attr = "_";
}
}
public boolean existsInCache(URL url, Set queryhashes) {
String hashes = yacySearch.set2string(queryhashes);
return retrieveFromCache(hashes, plasmaURL.urlHash(url)) != null;
}
public TextSnippet retrieveTextSnippet(URL url, Set queryhashes, boolean fetchOnline, boolean pre, int snippetMaxLength, int timeout) {
// heise = "0OQUNU3JSs05"
if (queryhashes.size() == 0) {
//System.out.println("found no queryhashes for URL retrieve " + url);
return new TextSnippet(url, null, ERROR_NO_HASH_GIVEN, queryhashes, "no query hashes given");
}
String urlhash = plasmaURL.urlHash(url);
// try to get snippet from snippetCache
int source = SOURCE_CACHE;
String wordhashes = yacySearch.set2string(queryhashes);
String line = retrieveFromCache(wordhashes, urlhash);
if (line != null) {
//System.out.println("found snippet for URL " + url + " in cache: " + line);
return new TextSnippet(url, line, source, null, null,(URL)this.faviconCache.get(urlhash));
}
/* ===========================================================================
* LOADING RESOURCE DATA
* =========================================================================== */
// if the snippet is not in the cache, we can try to get it from the htcache
long resContentLength = 0;
InputStream resContent = null;
IResourceInfo resInfo = null;
try {
// trying to load the resource from the cache
resContent = this.cacheManager.getResourceContentStream(url);
if (resContent != null) {
// if the content was found
resContentLength = this.cacheManager.getResourceContentLength(url);
} else if (fetchOnline) {
// if not found try to download it
// download resource using the crawler and keep resource in memory if possible
plasmaHTCache.Entry entry = loadResourceFromWeb(url, timeout, true, true);
// getting resource metadata (e.g. the http headers for http resources)
if (entry != null) {
resInfo = entry.getDocumentInfo();
// read resource body (if it is there)
byte []resourceArray = entry.cacheArray();
if (resourceArray != null) {
resContent = new ByteArrayInputStream(resourceArray);
resContentLength = resourceArray.length;
} else {
resContent = this.cacheManager.getResourceContentStream(url);
resContentLength = this.cacheManager.getResourceContentLength(url);
}
}
// if it is still not available, report an error
if (resContent == null) return new TextSnippet(url, null, ERROR_RESOURCE_LOADING, queryhashes, "error loading resource, plasmaHTCache.Entry cache is NULL");
source = SOURCE_WEB;
} else {
return new TextSnippet(url, null, ERROR_SOURCE_LOADING, queryhashes, "no resource available");
}
} catch (Exception e) {
if (!(e instanceof plasmaCrawlerException)) e.printStackTrace();
return new TextSnippet(url, null, ERROR_SOURCE_LOADING, queryhashes, "error loading resource: " + e.getMessage());
}
/* ===========================================================================
* PARSING RESOURCE
* =========================================================================== */
plasmaParserDocument document = null;
try {
document = parseDocument(url, resContentLength, resContent, resInfo);
} catch (ParserException e) {
return new TextSnippet(url, null, ERROR_PARSER_FAILED, queryhashes, e.getMessage()); // cannot be parsed
} finally {
try { resContent.close(); } catch (Exception e) {/* ignore this */}
}
if (document == null) return new TextSnippet(url, null, ERROR_PARSER_FAILED, queryhashes, "parser error/failed"); // cannot be parsed
/* ===========================================================================
* COMPUTE SNIPPET
* =========================================================================== */
URL resFavicon = document.getFavicon();
if (resFavicon != null) this.faviconCache.put(urlhash,resFavicon);
// we have found a parseable non-empty file: use the lines
// compute snippet from text
final Iterator sentences = document.getSentences(pre);
if (sentences == null) return new TextSnippet(url, null, ERROR_PARSER_NO_LINES, queryhashes, "parser returned no sentences",resFavicon);
Object[] tsr = computeTextSnippet(sentences, queryhashes, snippetMaxLength);
String textline = (tsr == null) ? null : (String) tsr[0];
Set remainingHashes = (tsr == null) ? queryhashes : (Set) tsr[1];
// compute snippet from media
String audioline = computeMediaSnippet(document.getAudiolinks(), queryhashes);
String videoline = computeMediaSnippet(document.getVideolinks(), queryhashes);
String appline = computeMediaSnippet(document.getApplinks(), queryhashes);
//String hrefline = computeMediaSnippet(document.getAnchors(), queryhashes);
//String imageline = computeMediaSnippet(document.getAudiolinks(), queryhashes);
line = "";
if (audioline != null) line += (line.length() == 0) ? audioline : "<br />" + audioline;
if (videoline != null) line += (line.length() == 0) ? videoline : "<br />" + videoline;
if (appline != null) line += (line.length() == 0) ? appline : "<br />" + appline;
//if (hrefline != null) line += (line.length() == 0) ? hrefline : "<br />" + hrefline;
if (textline != null) line += (line.length() == 0) ? textline : "<br />" + textline;
if ((line == null) || (remainingHashes.size() > 0)) return new TextSnippet(url, null, ERROR_NO_MATCH, remainingHashes, "no matching snippet found",resFavicon);
if (line.length() > snippetMaxLength) line = line.substring(0, snippetMaxLength);
// finally store this snippet in our own cache
storeToCache(wordhashes, urlhash, line);
document.close();
return new TextSnippet(url, line, source, null, null, resFavicon);
}
/**
* Tries to load and parse a resource specified by it's URL.
* If the resource is not stored in cache and if fetchOnline is set the
* this function tries to download the resource from web.
*
* @param url the URL of the resource
* @param fetchOnline specifies if the resource should be loaded from web if it'as not available in the cache
* @return the parsed document as {@link plasmaParserDocument}
*/
public plasmaParserDocument retrieveDocument(URL url, boolean fetchOnline, int timeout, boolean forText) {
// load resource
long resContentLength = 0;
InputStream resContent = null;
IResourceInfo resInfo = null;
try {
// trying to load the resource from the cache
resContent = this.cacheManager.getResourceContentStream(url);
if (resContent != null) {
// if the content was found
resContentLength = this.cacheManager.getResourceContentLength(url);
} else if (fetchOnline) {
// if not found try to download it
// download resource using the crawler and keep resource in memory if possible
plasmaHTCache.Entry entry = loadResourceFromWeb(url, timeout, true, forText);
// getting resource metadata (e.g. the http headers for http resources)
if (entry != null) {
resInfo = entry.getDocumentInfo();
// read resource body (if it is there)
byte []resourceArray = entry.cacheArray();
if (resourceArray != null) {
resContent = new ByteArrayInputStream(resourceArray);
resContentLength = resourceArray.length;
} else {
resContent = this.cacheManager.getResourceContentStream(url);
resContentLength = this.cacheManager.getResourceContentLength(url);
}
}
// if it is still not available, report an error
if (resContent == null) {
serverLog.logFine("snippet fetch", "plasmaHTCache.Entry cache is NULL for url " + url);
return null;
}
} else {
serverLog.logFine("snippet fetch", "no resource available for url " + url);
return null;
}
} catch (Exception e) {
serverLog.logFine("snippet fetch", "error loading resource: " + e.getMessage() + " for url " + url);
return null;
}
// parse resource
plasmaParserDocument document = null;
try {
document = parseDocument(url, resContentLength, resContent, resInfo);
} catch (ParserException e) {
serverLog.logFine("snippet fetch", "parser error " + e.getMessage() + " for url " + url);
return null;
} finally {
try { resContent.close(); } catch (Exception e) {}
}
return document;
}
public void storeToCache(String wordhashes, String urlhash, String snippet) {
// generate key
String key = urlhash + wordhashes;
// do nothing if snippet is known
if (snippetsCache.containsKey(key)) return;
// learn new snippet
snippetsScore.addScore(key, snippetsScoreCounter++);
snippetsCache.put(key, snippet);
// care for counter
if (snippetsScoreCounter == java.lang.Integer.MAX_VALUE) {
snippetsScoreCounter = 0;
snippetsScore = new kelondroMScoreCluster();
snippetsCache = new HashMap();
}
// flush cache if cache is full
while (snippetsCache.size() > maxCache) {
key = (String) snippetsScore.getMinObject();
snippetsScore.deleteScore(key);
snippetsCache.remove(key);
}
}
private String retrieveFromCache(String wordhashes, String urlhash) {
// generate key
String key = urlhash + wordhashes;
return (String) snippetsCache.get(key);
}
private String computeMediaSnippet(Map media, Set queryhashes) {
Iterator i = media.entrySet().iterator();
Map.Entry entry;
String url, desc;
Set s;
String result = "";
while (i.hasNext()) {
entry = (Map.Entry) i.next();
url = (String) entry.getKey();
desc = (String) entry.getValue();
s = removeAppearanceHashes(url, queryhashes);
if (s.size() == 0) {
result += "<br /><a href=\"" + url + "\">" + ((desc.length() == 0) ? url : desc) + "</a>";
continue;
}
s = removeAppearanceHashes(desc, s);
if (s.size() == 0) {
result += "<br /><a href=\"" + url + "\">" + ((desc.length() == 0) ? url : desc) + "</a>";
continue;
}
}
if (result.length() == 0) return null;
return result.substring(6);
}
private Object[] /*{String - the snippet, Set - remaining hashes}*/
computeTextSnippet(Iterator sentences, Set queryhashes, int maxLength) {
try {
if (sentences == null) return null;
if ((queryhashes == null) || (queryhashes.size() == 0)) return null;
Iterator j;
HashMap hs;
StringBuffer sentence;
TreeMap os = new TreeMap();
int uniqCounter = 9999;
int score;
while (sentences.hasNext()) {
sentence = (StringBuffer) sentences.next();
hs = hashSentence(sentence.toString());
j = queryhashes.iterator();
score = 0;
while (j.hasNext()) {if (hs.containsKey((String) j.next())) score++;}
if (score > 0) {
os.put(new Integer(1000000 * score - sentence.length() * 10000 + uniqCounter--), sentence);
}
}
String result;
Set remaininghashes;
while (os.size() > 0) {
sentence = (StringBuffer) os.remove((Integer) os.lastKey()); // sentence with the biggest score
Object[] tsr = computeTextSnippet(sentence.toString(), queryhashes, maxLength);
if (tsr == null) continue;
result = (String) tsr[0];
if ((result != null) && (result.length() > 0)) {
remaininghashes = (Set) tsr[1];
if (remaininghashes.size() == 0) {
// we have found the snippet
return new Object[]{result, remaininghashes};
} else if (remaininghashes.size() < queryhashes.size()) {
// the result has not all words in it.
// find another sentence that represents the missing other words
// and find recursively more sentences
maxLength = maxLength - result.length();
if (maxLength < 20) maxLength = 20;
tsr = computeTextSnippet(os.values().iterator(), remaininghashes, maxLength);
if (tsr == null) return null;
String nextSnippet = (String) tsr[0];
if (nextSnippet == null) return tsr;
return new Object[]{result + (" / " + nextSnippet), tsr[1]};
} else {
// error
//assert remaininghashes.size() < queryhashes.size() : "remaininghashes.size() = " + remaininghashes.size() + ", queryhashes.size() = " + queryhashes.size() + ", sentence = '" + sentence + "', result = '" + result + "'";
continue;
}
}
}
return null;
} catch (IndexOutOfBoundsException e) {
log.logSevere("computeSnippet: error with string generation", e);
return new Object[]{null, queryhashes};
}
}
private Object[] /*{String - the snippet, Set - remaining hashes}*/
computeTextSnippet(String sentence, Set queryhashes, int maxLength) {
try {
if (sentence == null) return null;
if ((queryhashes == null) || (queryhashes.size() == 0)) return null;
Iterator j;
HashMap hs;
String hash;
// find all hashes that appear in the sentence
hs = hashSentence(sentence);
j = queryhashes.iterator();
Integer pos;
int p, minpos = sentence.length(), maxpos = -1;
HashSet remainingHashes = new HashSet();
while (j.hasNext()) {
hash = (String) j.next();
pos = (Integer) hs.get(hash);
if (pos == null) {
remainingHashes.add(hash);
} else {
p = pos.intValue();
if (p > maxpos) maxpos = p;
if (p < minpos) minpos = p;
}
}
// check result size
maxpos = maxpos + 10;
if (maxpos > sentence.length()) maxpos = sentence.length();
if (minpos < 0) minpos = 0;
// we have a result, but is it short enough?
if (maxpos - minpos + 10 > maxLength) {
// the string is too long, even if we cut at both ends
// so cut here in the middle of the string
int lenb = sentence.length();
sentence = sentence.substring(0, (minpos + 20 > sentence.length()) ? sentence.length() : minpos + 20).trim() +
" [..] " +
sentence.substring((maxpos + 26 > sentence.length()) ? sentence.length() : maxpos + 26).trim();
maxpos = maxpos + lenb - sentence.length() + 6;
}
if (maxpos > maxLength) {
// the string is too long, even if we cut it at the end
// so cut it here at both ends at once
int newlen = maxpos - minpos + 10;
int around = (maxLength - newlen) / 2;
sentence = "[..] " + sentence.substring(minpos - around, ((maxpos + around) > sentence.length()) ? sentence.length() : (maxpos + around)).trim() + " [..]";
minpos = around;
maxpos = sentence.length() - around - 5;
}
if (sentence.length() > maxLength) {
// trim sentence, 1st step (cut at right side)
sentence = sentence.substring(0, maxpos).trim() + " [..]";
}
if (sentence.length() > maxLength) {
// trim sentence, 2nd step (cut at left side)
sentence = "[..] " + sentence.substring(minpos).trim();
}
if (sentence.length() > maxLength) {
// trim sentence, 3rd step (cut in the middle)
sentence = sentence.substring(6, 20).trim() + " [..] " + sentence.substring(sentence.length() - 26, sentence.length() - 6).trim();
}
return new Object[] {sentence, remainingHashes};
} catch (IndexOutOfBoundsException e) {
log.logSevere("computeSnippet: error with string generation", e);
return null;
}
}
public ArrayList retrieveMediaSnippets(URL url, Set queryhashes, String mediatype, boolean fetchOnline, int timeout) {
if (queryhashes.size() == 0) {
serverLog.logFine("snippet fetch", "no query hashes given for url " + url);
return new ArrayList();
}
if (mediatype == null) mediatype = "";
plasmaParserDocument document = retrieveDocument(url, fetchOnline, timeout, false);
ArrayList a = new ArrayList();
if (document != null) {
if ((mediatype.length() == 0) || (mediatype.equals("audio"))) a.addAll(computeMediaSnippets(document, queryhashes, "audio"));
if ((mediatype.length() == 0) || (mediatype.equals("video"))) a.addAll(computeMediaSnippets(document, queryhashes, "video"));
if ((mediatype.length() == 0) || (mediatype.equals("app" ))) a.addAll(computeMediaSnippets(document, queryhashes, "app"));
if ((mediatype.length() == 0) || (mediatype.equals("image"))) a.addAll(computeImageSnippets(document, queryhashes));
}
return a;
}
public ArrayList computeMediaSnippets(plasmaParserDocument document, Set queryhashes, String mediatype) {
if (document == null) return new ArrayList();
Map media = null;
if (mediatype.equals("audio")) media = document.getAudiolinks();
else if (mediatype.equals("video")) media = document.getVideolinks();
else if (mediatype.equals("app")) media = document.getApplinks();
if (media == null) return null;
Iterator i = media.entrySet().iterator();
Map.Entry entry;
String url, desc;
Set s;
ArrayList result = new ArrayList();
while (i.hasNext()) {
entry = (Map.Entry) i.next();
url = (String) entry.getKey();
desc = (String) entry.getValue();
//result.add(new MediaSnippet(mediatype, url, (desc.length() == 0) ? url : desc, null));
s = removeAppearanceHashes(url, queryhashes);
if (s.size() == 0) {
result.add(new MediaSnippet(mediatype, url, desc, null));
continue;
}
s = removeAppearanceHashes(desc, s);
if (s.size() == 0) {
result.add(new MediaSnippet(mediatype, url, desc, null));
continue;
}
}
return result;
}
public ArrayList computeImageSnippets(plasmaParserDocument document, Set queryhashes) {
TreeSet images = document.getImages();
Iterator i = images.iterator();
htmlFilterImageEntry ientry;
String url, desc;
Set s;
ArrayList result = new ArrayList();
while (i.hasNext()) {
ientry = (htmlFilterImageEntry) i.next();
url = (String) ientry.url().toNormalform();
desc = (String) ientry.alt();
//result.add(new MediaSnippet("image", url, (desc.length() == 0) ? url : desc, ientry.width() + " x " + ientry.height()));
s = removeAppearanceHashes(url, queryhashes);
if (s.size() == 0) {
result.add(new MediaSnippet("image", url, desc, ientry.width() + " x " + ientry.height()));
continue;
}
s = removeAppearanceHashes(desc, s);
if (s.size() == 0) {
result.add(new MediaSnippet("image", url, desc, ientry.width() + " x " + ientry.height()));
continue;
}
}
return result;
}
private Set removeAppearanceHashes(String sentence, Set queryhashes) {
// remove all hashes that appear in the sentence
if (sentence == null) return queryhashes;
HashMap hs = hashSentence(sentence);
Iterator j = queryhashes.iterator();
String hash;
Integer pos;
Set remaininghashes = new HashSet();
while (j.hasNext()) {
hash = (String) j.next();
pos = (Integer) hs.get(hash);
if (pos == null) {
remaininghashes.add(new String(hash));
}
}
return remaininghashes;
}
private HashMap hashSentence(String sentence) {
// generates a word-wordPos mapping
HashMap map = new HashMap();
Enumeration words = plasmaCondenser.wordTokenizer(sentence, "UTF-8", 0);
int pos = 0;
StringBuffer word;
while (words.hasMoreElements()) {
word = (StringBuffer) words.nextElement();
map.put(plasmaCondenser.word2hash(new String(word)), new Integer(pos));
pos += word.length() + 1;
}
return map;
}
public plasmaParserDocument parseDocument(URL url, long contentLength, InputStream resourceStream) throws ParserException {
return parseDocument(url, contentLength, resourceStream, null);
}
/**
* Parse the resource
* @param url the URL of the resource
* @param contentLength the contentLength of the resource
* @param resourceStream the resource body as stream
* @param docInfo metadata about the resource
* @return the extracted data
* @throws ParserException
*/
public plasmaParserDocument parseDocument(URL url, long contentLength, InputStream resourceStream, IResourceInfo docInfo) throws ParserException {
try {
if (resourceStream == null) return null;
// STEP 1: if no resource metadata is available, try to load it from cache
if (docInfo == null) {
// try to get the header from the htcache directory
try {
docInfo = this.cacheManager.loadResourceInfo(url);
} catch (Exception e) {
// ignore this. resource info loading failed
}
}
// STEP 2: if the metadata is still null try to download it from web
if ((docInfo == null) && (url.getProtocol().startsWith("http"))) {
// TODO: we need a better solution here
// e.g. encapsulate this in the crawlLoader class
// getting URL mimeType
try {
httpHeader header = httpc.whead(url, url.getHost(), 10000, null, null, this.sb.remoteProxyConfig);
docInfo = this.cacheManager.getResourceInfoFactory().buildResourceInfoObj(url, header);
} catch (Exception e) {
// ingore this. http header download failed
}
}
// STEP 3: if the metadata is still null try to guess the mimeType of the resource
if (docInfo == null) {
String filename = this.cacheManager.getCachePath(url).getName();
int p = filename.lastIndexOf('.');
if ( // if no extension is available
(p < 0) ||
// or the extension is supported by one of the parsers
((p >= 0) && (plasmaParser.supportedFileExtContains(filename.substring(p + 1))))
) {
String supposedMime = "text/html";
// if the mimeType Parser is installed we can set the mimeType to null to force
// a mimetype detection
if (plasmaParser.supportedMimeTypesContains("application/octet-stream")) {
supposedMime = null;
} else if (p != -1){
// otherwise we try to determine the mimeType per file Extension
supposedMime = plasmaParser.getMimeTypeByFileExt(filename.substring(p + 1));
}
return this.parser.parseSource(url, supposedMime, null, contentLength, resourceStream);
}
return null;
}
if (plasmaParser.supportedMimeTypesContains(docInfo.getMimeType())) {
return this.parser.parseSource(url, docInfo.getMimeType(), docInfo.getCharacterEncoding(), contentLength, resourceStream);
}
return null;
} catch (InterruptedException e) {
// interruption of thread detected
return null;
}
}
/**
*
* @param url
* @param fetchOnline
* @param socketTimeout
* @return an Object array containing
* <table>
* <tr><td>[0]</td><td>the content as {@link InputStream}</td></tr>
* <tr><td>[1]</td><td>the content-length as {@link Integer}</td></tr>
* </table>
*/
public Object[] getResource(URL url, boolean fetchOnline, int socketTimeout, boolean forText) {
// load the url as resource from the web
try {
long contentLength = -1;
// trying to load the resource body from cache
InputStream resource = this.cacheManager.getResourceContentStream(url);
if (resource != null) {
contentLength = this.cacheManager.getResourceContentLength(url);
} else if (fetchOnline) {
// if the content is not available in cache try to download it from web
// try to download the resource using a crawler
plasmaHTCache.Entry entry = loadResourceFromWeb(url, (socketTimeout < 0) ? -1 : socketTimeout, true, forText);
// read resource body (if it is there)
byte[] resourceArray = entry.cacheArray();
// in case that the reosurce was not in ram, read it from disk
if (resourceArray == null) {
resource = this.cacheManager.getResourceContentStream(url);
contentLength = this.cacheManager.getResourceContentLength(url);
} else {
resource = new ByteArrayInputStream(resourceArray);
contentLength = resourceArray.length;
}
} else {
return null;
}
return new Object[]{resource,new Long(contentLength)};
} catch (IOException e) {
return null;
}
}
public plasmaHTCache.Entry loadResourceFromWeb(
URL url,
int socketTimeout,
boolean keepInMemory,
boolean forText
) throws plasmaCrawlerException {
plasmaHTCache.Entry result = this.sb.cacheLoader.loadSync(
url, // the url
"", // name of the url, from anchor tag <a>name</a>
null, // referer
yacyCore.seedDB.mySeed.hash, // initiator
0, // depth
(forText) ? sb.defaultTextSnippetProfile : sb.defaultMediaSnippetProfile, // crawl profile
socketTimeout,
keepInMemory
);
return result;
}
public String failConsequences(TextSnippet snippet, Set queryhashes) {
// problems with snippet fetch
if (yacyCore.seedDB.mySeed.isVirgin()) return snippet.getError() + " (no consequences, no network connection)"; // no consequences if we do not have a network connection
String urlHash = plasmaURL.urlHash(snippet.getUrl());
String querystring = kelondroMSetTools.setToString(snippet.getRemainingHashes(), ' ');
if ((snippet.getErrorCode() == ERROR_SOURCE_LOADING) ||
(snippet.getErrorCode() == ERROR_RESOURCE_LOADING) ||
(snippet.getErrorCode() == ERROR_PARSER_FAILED) ||
(snippet.getErrorCode() == ERROR_PARSER_NO_LINES)) {
log.logInfo("error: '" + snippet.getError() + "', remove url = " + snippet.getUrl().toNormalform() + ", cause: " + snippet.getError());
sb.wordIndex.loadedURL.remove(urlHash);
sb.wordIndex.removeHashReferences(queryhashes, urlHash);
}
if (snippet.getErrorCode() == ERROR_NO_MATCH) {
log.logInfo("error: '" + snippet.getError() + "', remove words '" + querystring + "' for url = " + snippet.getUrl().toNormalform() + ", cause: " + snippet.getError());
sb.wordIndex.removeHashReferences(snippet.remaingHashes, urlHash);
}
return snippet.getError();
}
}
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