Java tutorial
/* * 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.document; /** * Syntactic sugar for encoding doubles as NumericDocValues * via {@link Double#doubleToRawLongBits(double)}. * <p> * Per-document double values can be retrieved via * {@link org.apache.lucene.index.LeafReader#getNumericDocValues(String)}. * <p> * <b>NOTE</b>: In most all cases this will be rather inefficient, * requiring eight bytes per document. Consider encoding double * values yourself with only as much precision as you require. */ public class DoubleDocValuesField extends NumericDocValuesField { /** * Creates a new DocValues field with the specified 64-bit double value * @param name field name * @param value 64-bit double value * @throws IllegalArgumentException if the field name is null */ public DoubleDocValuesField(String name, double value) { super(name, Double.doubleToRawLongBits(value)); } @Override public void setDoubleValue(double value) { super.setLongValue(Double.doubleToRawLongBits(value)); } @Override public void setLongValue(long value) { throw new IllegalArgumentException("cannot change value type from Double to Long"); } }