Java tutorial
package org.apache.tika.batch.fs; /* * 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. */ import java.io.IOException; import java.net.URL; import java.nio.file.Path; import java.nio.file.Paths; import java.util.HashMap; import java.util.Map; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.DefaultParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.Option; import org.apache.commons.cli.Options; import org.apache.commons.io.IOUtils; import org.apache.tika.batch.BatchProcess; import org.apache.tika.batch.BatchProcessDriverCLI; import org.apache.tika.batch.ParallelFileProcessingResult; import org.apache.tika.batch.builders.BatchProcessBuilder; import org.apache.tika.batch.builders.CommandLineParserBuilder; import org.apache.tika.io.TikaInputStream; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.slf4j.MarkerFactory; public class FSBatchProcessCLI { public static String FINISHED_STRING = "Main thread in TikaFSBatchCLI has finished processing."; private static final Logger LOG = LoggerFactory.getLogger(FSBatchProcessCLI.class); private final Options options; public FSBatchProcessCLI(String[] args) throws IOException { TikaInputStream configIs = null; try { configIs = getConfigInputStream(args, true); CommandLineParserBuilder builder = new CommandLineParserBuilder(); options = builder.build(configIs); } finally { IOUtils.closeQuietly(configIs); } } public void usage() { HelpFormatter helpFormatter = new HelpFormatter(); helpFormatter.printHelp("tika filesystem batch", options); } private TikaInputStream getConfigInputStream(String[] args, boolean logDefault) throws IOException { TikaInputStream is = null; Path batchConfigFile = getConfigFile(args); if (batchConfigFile != null) { //this will throw IOException if it can't find a specified config file //better to throw an exception than silently back off to default. is = TikaInputStream.get(batchConfigFile); } else { if (logDefault) { LOG.info( "No config file set via -bc, relying on tika-app-batch-config.xml or default-tika-batch-config.xml"); } //test to see if there's a tika-app-batch-config.xml on the path URL config = FSBatchProcessCLI.class.getResource("/tika-app-batch-config.xml"); if (config != null) { is = TikaInputStream.get(FSBatchProcessCLI.class.getResourceAsStream("/tika-app-batch-config.xml")); } else { is = TikaInputStream .get(FSBatchProcessCLI.class.getResourceAsStream("default-tika-batch-config.xml")); } } return is; } private void execute(String[] args) throws Exception { CommandLineParser cliParser = new DefaultParser(); CommandLine line = cliParser.parse(options, args); if (line.hasOption("help")) { usage(); System.exit(BatchProcessDriverCLI.PROCESS_NO_RESTART_EXIT_CODE); } Map<String, String> mapArgs = new HashMap<String, String>(); for (Option option : line.getOptions()) { String v = option.getValue(); if (v == null || v.equals("")) { v = "true"; } mapArgs.put(option.getOpt(), v); } BatchProcessBuilder b = new BatchProcessBuilder(); TikaInputStream is = null; BatchProcess process = null; try { is = getConfigInputStream(args, false); process = b.build(is, mapArgs); } finally { IOUtils.closeQuietly(is); } final Thread mainThread = Thread.currentThread(); ExecutorService executor = Executors.newSingleThreadExecutor(); Future<ParallelFileProcessingResult> futureResult = executor.submit(process); ParallelFileProcessingResult result = futureResult.get(); System.out.println(FINISHED_STRING); System.out.println("\n"); System.out.println(result.toString()); System.exit(result.getExitStatus()); } private Path getConfigFile(String[] args) { Path configFile = null; for (int i = 0; i < args.length; i++) { if (args[i].equals("-bc") || args[i].equals("-batch-config")) { if (i < args.length - 1) { configFile = Paths.get(args[i + 1]); } } } return configFile; } public static void main(String[] args) throws Exception { try { FSBatchProcessCLI cli = new FSBatchProcessCLI(args); cli.execute(args); } catch (Throwable t) { t.printStackTrace(); LOG.error(MarkerFactory.getMarker("FATAL"), "Fatal exception from FSBatchProcessCLI: {}", t.getMessage(), t); System.exit(BatchProcessDriverCLI.PROCESS_NO_RESTART_EXIT_CODE); } } }