org.apache.lucene.search.suggest.FileDictionary Maven / Gradle / Ivy
package org.apache.lucene.search.suggest;
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.*;
import java.util.Comparator;
import org.apache.lucene.search.spell.Dictionary;
import org.apache.lucene.search.spell.TermFreqIterator;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.IOUtils;
/**
* Dictionary represented by a text file.
*
* Format allowed: 1 string per line, optionally with a tab-separated integer value:
* word1 TAB 100
* word2 word3 TAB 101
* word4 word5 TAB 102
*/
public class FileDictionary implements Dictionary {
private BufferedReader in;
private String line;
private boolean done = false;
public FileDictionary(InputStream dictFile) {
in = new BufferedReader(new InputStreamReader(dictFile));
}
/**
* Creates a dictionary based on a reader.
*/
public FileDictionary(Reader reader) {
in = new BufferedReader(reader);
}
public TermFreqIterator getWordsIterator() {
return new FileIterator();
}
final class FileIterator implements TermFreqIterator {
private long curFreq;
private final BytesRef spare = new BytesRef();
public long weight() {
return curFreq;
}
//@Override - not until Java 6
public BytesRef next() throws IOException {
if (done) {
return null;
}
line = in.readLine();
if (line != null) {
String[] fields = line.split("\t");
if (fields.length > 1) {
// keep reading floats for bw compat
try {
curFreq = Long.parseLong(fields[1]);
} catch (NumberFormatException e) {
curFreq = (long)Double.parseDouble(fields[1]);
}
spare.copyChars(fields[0]);
} else {
spare.copyChars(line);
curFreq = 1;
}
return spare;
} else {
done = true;
IOUtils.close(in);
return null;
}
}
//@Override - not until Java 6
public Comparator getComparator() {
return null;
}
}
}