| /* |
| * 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.facet.compare; |
| |
| import org.apache.solr.analytics.facet.SortableFacet.FacetBucket; |
| |
| /** |
| * A comparator used to sort the facet-value buckets of facet. |
| */ |
| public class ExpressionComparator<T extends Comparable<T>> extends FacetResultsComparator { |
| private final String expression; |
| |
| /** |
| * Create an entry comparator comparing the given expression. |
| * |
| * @param expression the name of the expression results to compare |
| */ |
| public ExpressionComparator(String expression) { |
| this.expression = expression; |
| } |
| |
| @SuppressWarnings("unchecked") |
| public int compare(FacetBucket b1, FacetBucket b2) { |
| T t1 = (T)b1.getResult(expression); |
| T t2 = (T)b2.getResult(expression); |
| if (t1 == null || t2 == null) { |
| return Boolean.compare(t2 == null, t1 == null) * resultMult; |
| } else { |
| return t1.compareTo(t2) * resultMult; |
| } |
| } |
| } |