org.azyva.dragom.tool.GenericModelVisitorJobInvokerTool.java Source code

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Here is the source code for org.azyva.dragom.tool.GenericModelVisitorJobInvokerTool.java

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/*
 * Copyright 2015 - 2017 AZYVA INC. INC.
 *
 * This file is part of Dragom.
 *
 * Dragom is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Dragom is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with Dragom.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.azyva.dragom.tool;

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.DefaultParser;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.commons.io.IOUtils;
import org.azyva.dragom.cliutil.CliUtil;
import org.azyva.dragom.execcontext.support.ExecContextHolder;
import org.azyva.dragom.job.ModelVisitorJob;
import org.azyva.dragom.model.NodePath;
import org.azyva.dragom.util.RuntimeExceptionUserError;
import org.azyva.dragom.util.Util;

/**
 * Generic tool wrapper for classes which implement {@link ModelVisitorJob}.
 *
 * <p>Many jobs which implement ModelVisitorJob, do not require complex invocation
 * arguments and can be invoked by this generic tool wrapper and avoid having to
 * introduce specific tool classes.
 * <p>
 * This tool first expects the following arguments:
 * <ul>
 * <li>Fully qualified name of the ModelVisitorJob implementation class
 * <li>Text resource for the help file
 * </ul>
 * These arguments are not validated as if they were specified by the user. They
 * are expected to be specified by a script that invokes the tool.
 * <p>
 * After these arguments, the regular user-level options and arguments are
 * expected.
 *
 * @author David Raymond
 */
public class GenericModelVisitorJobInvokerTool {
    /**
     * Indicates that the class has been initialized.
     */
    private static boolean indInit;

    /**
     * Options for parsing the command line.
     */
    private static Options options;

    /**
     * Method main.
     *
     * @param args Arguments.
     */
    public static void main(String[] args) {
        String modelVisitorJobClass;
        String helpResource;
        DefaultParser defaultParser;
        CommandLine commandLine = null;
        Constructor<? extends ModelVisitorJob> constructor;
        ModelVisitorJob modelVisitorJob;
        int exitStatus;

        modelVisitorJobClass = args[0];
        helpResource = args[1];

        args = Arrays.copyOfRange(args, 2, args.length);

        GenericModelVisitorJobInvokerTool.init();

        modelVisitorJob = null;

        try {
            defaultParser = new DefaultParser();

            try {
                commandLine = defaultParser.parse(GenericModelVisitorJobInvokerTool.options, args);
            } catch (ParseException pe) {
                throw new RuntimeExceptionUserError(MessageFormat.format(
                        CliUtil.getLocalizedMsgPattern(CliUtil.MSG_PATTERN_KEY_ERROR_PARSING_COMMAND_LINE),
                        pe.getMessage(), CliUtil.getHelpCommandLineOption()));
            }

            if (CliUtil.hasHelpOption(commandLine)) {
                GenericModelVisitorJobInvokerTool.help(helpResource);
            } else {
                List<NodePath> listNodePathBase;

                args = commandLine.getArgs();

                CliUtil.setupExecContext(commandLine, true);

                if (args.length != 0) {
                    listNodePathBase = new ArrayList<>();

                    for (String arg : args) {
                        try {
                            listNodePathBase.add(NodePath.parse(arg));
                        } catch (java.text.ParseException pe) {
                            throw new RuntimeExceptionUserError(MessageFormat.format(
                                    CliUtil.getLocalizedMsgPattern(
                                            CliUtil.MSG_PATTERN_KEY_ERROR_PARSING_COMMAND_LINE),
                                    pe.getMessage(), CliUtil.getHelpCommandLineOption()));
                        }
                    }
                } else {
                    listNodePathBase = null;
                }

                try {
                    constructor = Class.forName(modelVisitorJobClass).asSubclass(ModelVisitorJob.class)
                            .getConstructor(List.class);
                    modelVisitorJob = constructor.newInstance(listNodePathBase);
                } catch (ClassNotFoundException | NoSuchMethodException | InvocationTargetException
                        | IllegalAccessException | InstantiationException e) {
                    throw new RuntimeException(e);
                }

                modelVisitorJob.performJob();
            }

            // Need to call before ExecContextHolder.endToolAndUnset.
            exitStatus = Util.getExitStatusAndShowReason();
        } catch (RuntimeExceptionUserError reue) {
            System.err.println(
                    CliUtil.getLocalizedMsgPattern(CliUtil.MSG_PATTERN_KEY_USER_ERROR_PREFIX) + reue.getMessage());
            exitStatus = 1;
        } catch (RuntimeException re) {
            re.printStackTrace();
            exitStatus = 1;
        } finally {
            ExecContextHolder.endToolAndUnset();
        }

        System.exit(exitStatus);
    }

    /**
     * Initializes the class.
     */
    private synchronized static void init() {
        if (!GenericModelVisitorJobInvokerTool.indInit) {
            Option option;
            GenericModelVisitorJobInvokerTool.options = new Options();

            CliUtil.initJavaUtilLogging();

            CliUtil.addStandardOptions(GenericModelVisitorJobInvokerTool.options);

            GenericModelVisitorJobInvokerTool.indInit = true;
        }
    }

    /**
     * Displays help information.
     *
     * @param resource Base name of the resource containing the help file.
     */
    private static void help(String resource) {
        try {
            IOUtils.copy(CliUtil.getLocalizedTextResourceReader(GenericModelVisitorJobInvokerTool.class, resource),
                    System.out);
        } catch (IOException ioe) {
            throw new RuntimeException(ioe);
        }
    }
}