/*
 * 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.lucene.queries.function.valuesource;

import java.io.IOException;
import java.util.Map;

import org.apache.lucene.index.DocValues;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.NumericDocValues;
import org.apache.lucene.queries.function.FunctionValues;
import org.apache.lucene.queries.function.docvalues.FloatDocValues;
import org.apache.lucene.search.SortField.Type;
import org.apache.lucene.search.SortField;
import org.apache.lucene.util.mutable.MutableValue;
import org.apache.lucene.util.mutable.MutableValueFloat;

Obtains float field values from LeafReader.getNumericDocValues and makes those values available as other numeric types, casting as needed.
/** * Obtains float field values from {@link org.apache.lucene.index.LeafReader#getNumericDocValues} and makes those * values available as other numeric types, casting as needed. */
public class FloatFieldSource extends FieldCacheSource { public FloatFieldSource(String field) { super(field); } @Override public String description() { return "float(" + field + ')'; } @Override public SortField getSortField(boolean reverse) { return new SortField(field, Type.FLOAT, reverse); } @Override public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException { final NumericDocValues arr = getNumericDocValues(context, readerContext); return new FloatDocValues(this) { int lastDocID; private float getValueForDoc(int doc) throws IOException { if (doc < lastDocID) { throw new IllegalArgumentException("docs were sent out-of-order: lastDocID=" + lastDocID + " vs docID=" + doc); } lastDocID = doc; int curDocID = arr.docID(); if (doc > curDocID) { curDocID = arr.advance(doc); } if (doc == curDocID) { return Float.intBitsToFloat((int)arr.longValue()); } else { return 0f; } } @Override public float floatVal(int doc) throws IOException { return getValueForDoc(doc); } @Override public boolean exists(int doc) throws IOException { getValueForDoc(doc); return arr.docID() == doc; } @Override public ValueFiller getValueFiller() { return new ValueFiller() { private final MutableValueFloat mval = new MutableValueFloat(); @Override public MutableValue getValue() { return mval; } @Override public void fillValue(int doc) throws IOException { mval.value = floatVal(doc); mval.exists = arr.docID() == doc; } }; } }; } protected NumericDocValues getNumericDocValues(Map context, LeafReaderContext readerContext) throws IOException { return DocValues.getNumeric(readerContext.reader(), field); } @Override public boolean equals(Object o) { if (o.getClass() != FloatFieldSource.class) return false; FloatFieldSource other = (FloatFieldSource)o; return super.equals(other); } @Override public int hashCode() { int h = Float.class.hashCode(); h += super.hashCode(); return h; } }