| /* |
| * 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 arq.examples.riot; |
| |
| import java.util.concurrent.ExecutorService ; |
| import java.util.concurrent.Executors ; |
| |
| import org.apache.jena.graph.Triple ; |
| import org.apache.jena.riot.RDFParser ; |
| import org.apache.jena.riot.lang.PipedRDFIterator ; |
| import org.apache.jena.riot.lang.PipedRDFStream ; |
| import org.apache.jena.riot.lang.PipedTriplesStream ; |
| |
| /** |
| * Example of using RIOT : iterate over output of parser run using a |
| * {@link PipedRDFStream} and a {@link PipedRDFIterator} |
| * |
| */ |
| public class ExRIOT7_ParserPiped { |
| |
| public static void main(String... argv) { |
| final String filename = "data.ttl"; |
| |
| // Create a PipedRDFStream to accept input and a PipedRDFIterator to |
| // consume it |
| // You can optionally supply a buffer size here for the |
| // PipedRDFIterator, see the documentation for details about recommended |
| // buffer sizes |
| PipedRDFIterator<Triple> iter = new PipedRDFIterator<>(); |
| final PipedRDFStream<Triple> inputStream = new PipedTriplesStream(iter); |
| |
| // PipedRDFStream and PipedRDFIterator need to be on different threads |
| ExecutorService executor = Executors.newSingleThreadExecutor(); |
| |
| // Create a runnable for our parser thread |
| Runnable parser = new Runnable() { |
| |
| @Override |
| public void run() { |
| RDFParser.source(filename).parse(inputStream); |
| } |
| }; |
| |
| // Start the parser on another thread |
| executor.submit(parser); |
| |
| // We will consume the input on the main thread here |
| |
| // We can now iterate over data as it is parsed, parsing only runs as |
| // far ahead of our consumption as the buffer size allows |
| while (iter.hasNext()) { |
| Triple next = iter.next(); |
| // Do something with each triple |
| } |
| } |
| |
| } |