| /** |
| * 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.marmotta.ldpath.model.functions.math; |
| |
| |
| import java.net.URI; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| |
| import org.apache.marmotta.ldpath.api.backend.NodeBackend; |
| import org.apache.marmotta.ldpath.api.backend.RDFBackend; |
| import org.apache.marmotta.ldpath.model.Constants; |
| import org.apache.marmotta.ldpath.model.transformers.DoubleTransformer; |
| |
| public class MaxFunction<Node> extends MathFunction<Node> { |
| |
| protected final DoubleTransformer<Node> doubleTransformer = new DoubleTransformer<Node>(); |
| protected final URI doubleType = URI.create(Constants.NS_XSD + "double"); |
| |
| @Override |
| public Collection<Node> apply(RDFBackend<Node> backend, Node context, |
| Collection<Node>... args) throws IllegalArgumentException { |
| |
| ArrayList<Node> result = new ArrayList<Node>(); |
| for (Collection<Node> arg : args) { |
| Node res = calc(backend, arg); |
| if (res != null) { |
| result.add(res); |
| } |
| } |
| return result; |
| } |
| |
| protected Node calc(RDFBackend<Node> backend, Collection<Node> arg) { |
| /* MAX */ |
| double d = Double.MIN_VALUE; |
| Node max = null; |
| for (Node n : arg) { |
| try { |
| Double val = doubleTransformer.transform(backend, n, null); |
| if (val > d) { |
| d = val; |
| max = n; |
| } |
| } catch (IllegalArgumentException e) { |
| // we just ignore non-numeric nodes |
| } |
| } |
| |
| return max; |
| } |
| |
| @Override |
| public String getDescription() { |
| return "select the max of each argument"; |
| } |
| |
| @Override |
| public String getSignature() { |
| return "fn:max(LiteralList l [, ...]) :: NumberLiteral(s)"; |
| } |
| |
| @Override |
| public String getLocalName() { |
| return "max"; |
| } |
| |
| } |