Java tutorial
/* * Licensed to CRATE Technology GmbH ("Crate") under one or more contributor * license agreements. See the NOTICE file distributed with this work for * additional information regarding copyright ownership. Crate 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. * * However, if you have executed another commercial license agreement * with Crate these terms will supersede the license and you may use the * software solely pursuant to the terms of the relevant commercial agreement. */ package io.crate.operation.reference.doc.lucene; import io.crate.exceptions.GroupByOnArrayUnsupportedException; import org.apache.lucene.index.AtomicReaderContext; import org.apache.lucene.index.SortedNumericDocValues; import org.apache.lucene.util.BytesRef; import org.elasticsearch.index.fielddata.IndexNumericFieldData; import org.elasticsearch.index.mapper.ip.IpFieldMapper; public class IpColumnReference extends FieldCacheExpression<IndexNumericFieldData, BytesRef> { private SortedNumericDocValues values; public IpColumnReference(String columnName) { super(columnName); } @Override public BytesRef value() { switch (values.count()) { case 0: return null; case 1: return new BytesRef(IpFieldMapper.longToIp(values.valueAt(0))); default: throw new GroupByOnArrayUnsupportedException(columnName()); } } @Override public void setNextDocId(int docId) { super.setNextDocId(docId); values.setDocument(docId); } @Override public void setNextReader(AtomicReaderContext context) { super.setNextReader(context); values = indexFieldData.load(context).getLongValues(); } }