| /* |
| * 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 org.apache.lucene.index.LeafReaderContext; |
| import org.apache.lucene.queries.function.FunctionValues; |
| import org.apache.lucene.queries.function.ValueSource; |
| import org.apache.lucene.queries.function.docvalues.FloatDocValues; |
| import org.apache.lucene.search.IndexSearcher; |
| |
| import java.io.IOException; |
| import java.util.Map; |
| |
| /** |
| * <code>LinearFloatFunction</code> implements a linear function over |
| * another {@link ValueSource}. |
| * <br> |
| * Normally Used as an argument to a {@link org.apache.lucene.queries.function.FunctionQuery} |
| * |
| * |
| */ |
| public class LinearFloatFunction extends ValueSource { |
| protected final ValueSource source; |
| protected final float slope; |
| protected final float intercept; |
| |
| public LinearFloatFunction(ValueSource source, float slope, float intercept) { |
| this.source = source; |
| this.slope = slope; |
| this.intercept = intercept; |
| } |
| |
| @Override |
| public String description() { |
| return slope + "*float(" + source.description() + ")+" + intercept; |
| } |
| |
| @Override |
| public FunctionValues getValues(Map context, LeafReaderContext readerContext) throws IOException { |
| final FunctionValues vals = source.getValues(context, readerContext); |
| return new FloatDocValues(this) { |
| @Override |
| public float floatVal(int doc) throws IOException { |
| return vals.floatVal(doc) * slope + intercept; |
| } |
| @Override |
| public boolean exists(int doc) throws IOException { |
| return vals.exists(doc); |
| } |
| @Override |
| public String toString(int doc) throws IOException { |
| return slope + "*float(" + vals.toString(doc) + ")+" + intercept; |
| } |
| }; |
| } |
| |
| @Override |
| public void createWeight(Map context, IndexSearcher searcher) throws IOException { |
| source.createWeight(context, searcher); |
| } |
| |
| @Override |
| public int hashCode() { |
| int h = Float.floatToIntBits(slope); |
| h = (h >>> 2) | (h << 30); |
| h += Float.floatToIntBits(intercept); |
| h ^= (h << 14) | (h >>> 19); |
| return h + source.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (LinearFloatFunction.class != o.getClass()) return false; |
| LinearFloatFunction other = (LinearFloatFunction)o; |
| return this.slope == other.slope |
| && this.intercept == other.intercept |
| && this.source.equals(other.source); |
| } |
| } |