/**
* 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.
*/
package org.apache.solr.search.function;
import org.apache.lucene.search.FieldCache;
import org.apache.lucene.index.IndexReader;
import java.io.IOException;
/** Internal class, subject to change.
* Serves as base class for DocValues based on StringIndex
**/
public abstract class StringIndexDocValues extends DocValues {
protected final FieldCache.StringIndex index;
protected final int[] order;
protected final String[] lookup;
protected final ValueSource vs;
public StringIndexDocValues(ValueSource vs, IndexReader reader, String field) throws IOException {
try {
index = FieldCache.DEFAULT.getStringIndex(reader, field);
} catch (RuntimeException e) {
throw new StringIndexException(field, e);
}
order = index.order;
lookup = index.lookup;
this.vs = vs;
}
protected abstract String toTerm(String readableValue);
@Override
public ValueSourceScorer getRangeScorer(IndexReader reader, String lowerVal, String upperVal, boolean includeLower, boolean includeUpper) {
// TODO: are lowerVal and upperVal in indexed form or not?
lowerVal = lowerVal == null ? null : toTerm(lowerVal);
upperVal = upperVal == null ? null : toTerm(upperVal);
int lower = Integer.MIN_VALUE;
if (lowerVal != null) {
lower = index.binarySearchLookup(lowerVal);
if (lower < 0) {
lower = -lower-1;
} else if (!includeLower) {
lower++;
}
}
int upper = Integer.MAX_VALUE;
if (upperVal != null) {
upper = index.binarySearchLookup(upperVal);
if (upper < 0) {
upper = -upper-2;
} else if (!includeUpper) {
upper--;
}
}
final int ll = lower;
final int uu = upper;
return new ValueSourceScorer(reader, this) {
@Override
public boolean matchesValue(int doc) {
int ord = order[doc];
return ord >= ll && ord <= uu;
}
};
}
@Override
public String toString(int doc) {
return vs.description() + '=' + strVal(doc);
}
public static final class StringIndexException extends RuntimeException {
public StringIndexException(final String fieldName,
final RuntimeException cause) {
super("Can't initialize StringIndex to generate (function) " +
"DocValues for field: " + fieldName, cause);
}
}
}