at.newmedialab.ldpath.backend.linkeddata.LDQuery.java Source code

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Here is the source code for at.newmedialab.ldpath.backend.linkeddata.LDQuery.java

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/*
 * Copyright (c) 2011 Salzburg Research.
 *
 * Licensed 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 at.newmedialab.ldpath.backend.linkeddata;

import at.newmedialab.ldpath.LDPath;
import at.newmedialab.ldpath.backend.sesame.GenericSesameBackend;
import at.newmedialab.ldpath.exception.LDPathParseException;
import ch.qos.logback.classic.Level;
import org.apache.commons.cli.*;
import org.openrdf.model.Resource;
import org.openrdf.model.Value;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;

/**
 * Command line application for querying input from files.
 * <p/>
 * Author: Sebastian Schaffert
 */
public class LDQuery {

    private static final Logger log = LoggerFactory.getLogger(LDQuery.class);

    public static void main(String[] args) {
        Options options = buildOptions();

        CommandLineParser parser = new PosixParser();
        try {
            CommandLine cmd = parser.parse(options, args);

            Level logLevel = Level.WARN;

            if (cmd.hasOption("loglevel")) {
                String logLevelName = cmd.getOptionValue("loglevel");
                if ("DEBUG".equals(logLevelName.toUpperCase())) {
                    logLevel = Level.DEBUG;
                } else if ("INFO".equals(logLevelName.toUpperCase())) {
                    logLevel = Level.INFO;
                } else if ("WARN".equals(logLevelName.toUpperCase())) {
                    logLevel = Level.WARN;
                } else if ("ERROR".equals(logLevelName.toUpperCase())) {
                    logLevel = Level.ERROR;
                } else {
                    log.error("unsupported log level: {}", logLevelName);
                }
            }

            if (logLevel != null) {
                for (String logname : new String[] { "at", "org", "net", "com" }) {

                    ch.qos.logback.classic.Logger logger = (ch.qos.logback.classic.Logger) LoggerFactory
                            .getLogger(logname);
                    logger.setLevel(logLevel);
                }
            }

            String format = null;
            if (cmd.hasOption("format")) {
                format = cmd.getOptionValue("format");
            }

            GenericSesameBackend backend;
            if (cmd.hasOption("store")) {
                backend = new LDPersistentBackend(new File(cmd.getOptionValue("store")));
            } else {
                backend = new LDMemoryBackend();
            }

            Resource context = null;
            if (cmd.hasOption("context")) {
                context = backend.getRepository().getValueFactory().createURI(cmd.getOptionValue("context"));
            }

            if (backend != null && context != null) {
                LDPath<Value> ldpath = new LDPath<Value>(backend);

                if (cmd.hasOption("path")) {
                    String path = cmd.getOptionValue("path");

                    for (Value v : ldpath.pathQuery(context, path, null)) {
                        System.out.println(v.stringValue());
                    }
                } else if (cmd.hasOption("program")) {
                    File file = new File(cmd.getOptionValue("program"));

                    Map<String, Collection<?>> result = ldpath.programQuery(context, new FileReader(file));

                    for (String field : result.keySet()) {
                        StringBuilder line = new StringBuilder();
                        line.append(field);
                        line.append(" = ");
                        line.append("{");
                        for (Iterator it = result.get(field).iterator(); it.hasNext();) {
                            line.append(it.next().toString());
                            if (it.hasNext()) {
                                line.append(", ");
                            }
                        }
                        line.append("}");
                        System.out.println(line);

                    }
                }
            }

            if (backend instanceof LDPersistentBackend) {
                ((LDPersistentBackend) backend).shutdown();
            }

        } catch (ParseException e) {
            System.err.println("invalid arguments");
            HelpFormatter formatter = new HelpFormatter();
            formatter.printHelp("LDQuery", options, true);
        } catch (LDPathParseException e) {
            System.err.println("path or program could not be parsed");
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            System.err.println("file or program could not be found");
            HelpFormatter formatter = new HelpFormatter();
            formatter.printHelp("LDQuery", options, true);
        } catch (IOException e) {
            System.err.println("could not access cache data directory");
            HelpFormatter formatter = new HelpFormatter();
            formatter.printHelp("LDQuery", options, true);
        }

    }

    private static Options buildOptions() {
        Options result = new Options();

        OptionGroup query = new OptionGroup();
        Option path = OptionBuilder.withArgName("path").hasArg()
                .withDescription("LD Path to evaluate on the file starting from the context").create("path");
        Option program = OptionBuilder.withArgName("file").hasArg()
                .withDescription("LD Path program to evaluate on the file starting from the context")
                .create("program");
        query.addOption(path);
        query.addOption(program);
        query.setRequired(true);
        result.addOptionGroup(query);

        Option context = OptionBuilder.withArgName("uri").hasArg()
                .withDescription("URI of the context node to start from").create("context");
        context.setRequired(true);
        result.addOption(context);

        Option loglevel = OptionBuilder.withArgName("level").hasArg()
                .withDescription("set the log level; default is 'warn'").create("loglevel");
        result.addOption(loglevel);

        Option store = OptionBuilder.withArgName("dir").hasArg()
                .withDescription("cache the retrieved data in this directory").create("store");
        result.addOption(store);

        return result;
    }

}