package org.apache.lucene.queries.function.valuesource;
/*
* 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.IOException;
import java.util.Map;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.index.BinaryDocValues;
import org.apache.lucene.index.FieldInfo;
import org.apache.lucene.index.FieldInfo.DocValuesType;
import org.apache.lucene.queries.function.FunctionValues;
import org.apache.lucene.queries.function.docvalues.DocTermsIndexDocValues;
import org.apache.lucene.search.FieldCache;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
/**
* An implementation for retrieving {@link FunctionValues} instances for string based fields.
*/
public class BytesRefFieldSource extends FieldCacheSource {
public BytesRefFieldSource(String field) {
super(field);
}
@Override
public FunctionValues getValues(Map context, AtomicReaderContext readerContext) throws IOException {
final FieldInfo fieldInfo = readerContext.reader().getFieldInfos().fieldInfo(field);
// To be sorted or not to be sorted, that is the question
// TODO: do it cleaner?
if (fieldInfo != null && fieldInfo.getDocValuesType() == DocValuesType.BINARY) {
final BinaryDocValues binaryValues = FieldCache.DEFAULT.getTerms(readerContext.reader(), field);
return new FunctionValues() {
@Override
public boolean exists(int doc) {
return true; // doc values are dense
}
@Override
public boolean bytesVal(int doc, BytesRef target) {
binaryValues.get(doc, target);
return target.length > 0;
}
public String strVal(int doc) {
final BytesRef bytes = new BytesRef();
return bytesVal(doc, bytes)
? bytes.utf8ToString()
: null;
}
@Override
public Object objectVal(int doc) {
return strVal(doc);
}
@Override
public String toString(int doc) {
return description() + '=' + strVal(doc);
}
};
} else {
return new DocTermsIndexDocValues(this, readerContext, field) {
@Override
protected String toTerm(String readableValue) {
return readableValue;
}
@Override
public Object objectVal(int doc) {
return strVal(doc);
}
@Override
public String toString(int doc) {
return description() + '=' + strVal(doc);
}
};
}
}
}