| /* |
| * 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.analytics.function.reduction; |
| |
| import java.util.function.UnaryOperator; |
| |
| import org.apache.solr.analytics.ExpressionFactory.CreatorFunction; |
| import org.apache.solr.analytics.function.ReductionFunction; |
| import org.apache.solr.analytics.function.reduction.data.CountCollector; |
| import org.apache.solr.analytics.function.reduction.data.CountCollector.ExpressionCountCollector; |
| import org.apache.solr.analytics.function.reduction.data.CountCollector.TotalCountCollector; |
| import org.apache.solr.analytics.value.AnalyticsValueStream; |
| import org.apache.solr.analytics.value.LongValue.AbstractLongValue; |
| import org.apache.solr.analytics.function.reduction.data.ReductionDataCollector; |
| import org.apache.solr.common.SolrException; |
| import org.apache.solr.common.SolrException.ErrorCode; |
| |
| /** |
| * A reduction function which either counts the number of Solr Documents for which the parameter expression exists, |
| * or the number of documents returned if no parameter is given. |
| */ |
| public class DocCountFunction extends AbstractLongValue implements ReductionFunction { |
| private CountCollector collector; |
| public static final String name = "doc_count"; |
| private final String exprStr; |
| public static final CreatorFunction creatorFunction = (params -> { |
| if (params.length == 0) { |
| return new DocCountFunction(); |
| } |
| if (params.length == 1) { |
| return new DocCountFunction(params[0]); |
| } |
| throw new SolrException(ErrorCode.BAD_REQUEST,"The "+name+" function accepts at most 1 paramater, " + params.length + " given."); |
| }); |
| |
| public DocCountFunction() { |
| this.collector = new TotalCountCollector(); |
| this.exprStr = AnalyticsValueStream.createExpressionString(name); |
| } |
| |
| public DocCountFunction(AnalyticsValueStream param) { |
| this.collector = new ExpressionCountCollector(param); |
| this.exprStr = AnalyticsValueStream.createExpressionString(name,param); |
| } |
| |
| @Override |
| public long getLong() { |
| return collector.docCount(); |
| } |
| @Override |
| public boolean exists() { |
| return true; |
| } |
| |
| @Override |
| public void synchronizeDataCollectors(UnaryOperator<ReductionDataCollector<?>> sync) { |
| collector = (CountCollector)sync.apply(collector); |
| } |
| |
| @Override |
| public String getExpressionStr() { |
| return exprStr; |
| } |
| @Override |
| public String getName() { |
| return name; |
| } |
| |
| @Override |
| public ExpressionType getExpressionType() { |
| return ExpressionType.REDUCTION; |
| } |
| } |