diff --git a/source/net/yacy/cora/language/synonyms/SynonymLibrary.java b/source/net/yacy/cora/language/synonyms/SynonymLibrary.java
new file mode 100644
index 000000000..63e564348
--- /dev/null
+++ b/source/net/yacy/cora/language/synonyms/SynonymLibrary.java
@@ -0,0 +1,112 @@
+/**
+ * Stemming
+ * Copyright 2012 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
+ * first published 01.10.2012 on http://yacy.net
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program in the file lgpl21.txt
+ * If not, see .
+ */
+
+package net.yacy.cora.language.synonyms;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.BlockingQueue;
+
+import org.apache.log4j.Logger;
+
+import net.yacy.cora.storage.Files;
+
+/**
+ * Stemming library: reads stemming files and creates a mapping from words to synonyms
+ * Stemming files must have a list of synonym words in each line of the input file.
+ * The words within one line must be separated by ','. Lines starting with '#' are
+ * comment files and are ignored. Each line can (but does not need to) have a '{'
+ * at the beginning of the line and '}' at the end (which would be the GSA format).
+ */
+public class SynonymLibrary {
+
+ Logger log = Logger.getLogger(SynonymLibrary.class);
+ private Map>> lib;
+
+ public SynonymLibrary(final File path) {
+ this.lib = new HashMap>>();
+ if (!path.exists() || !path.isDirectory()) return;
+ final String[] files = path.list();
+ for (final String f: files) {
+ File ff = new File(path, f);
+ String line;
+ try {
+ BlockingQueue list = Files.concurentLineReader(ff, 1000);
+ while ((line = list.take()) != Files.POISON_LINE) {
+ line = line.trim();
+ if (line.length() == 0 || line.charAt(0) == '#') continue;
+ if (line.charAt(line.length() - 1) == '}') line = line.substring(0, line.length() - 1);
+ if (line.charAt(0) == '{') line = line.substring(1);
+ String[] words = line.split(",");
+ Set synonyms = new HashSet();
+ Set keys = new HashSet();
+ for (String s: words) {
+ s = s.trim();
+ if (s.length() < 2) continue;
+ String t = s.toLowerCase();
+ synonyms.add(t);
+ keys.add(t.substring(0, 2));
+ }
+ for (String key: keys) {
+ List> symsetlist = this.lib.get(key);
+ if (symsetlist == null) {
+ symsetlist = new ArrayList>();
+ this.lib.put(key, symsetlist);
+ }
+ symsetlist.add(synonyms);
+ }
+ }
+ } catch (Throwable e) {
+ log.warn("cannot read stemming file " + f, e);
+ }
+ }
+ }
+
+ /**
+ * for a given word, return a list of synonym words
+ * @param word
+ * @return a list of synonyms bot without the requested word
+ */
+ public Set getSynonyms(String word) {
+ word = word.toLowerCase();
+ if (word.length() < 2) return null;
+ String key = word.substring(0, 2);
+ List> symsetlist = this.lib.get(key);
+ if (symsetlist == null) return null;
+ for (Set symset: symsetlist) {
+ if (symset.contains(word)) {
+ // create a new set containing all but the one word
+ Set returnSet = new HashSet();
+ for (String synonym: symset) {
+ if (synonym.equals(word)) continue;
+ returnSet.add(synonym);
+ }
+ return returnSet;
+ }
+ }
+ return null;
+ }
+
+}