de.ailis.wlandsuite.cli.CLIProg.java Source code

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Here is the source code for de.ailis.wlandsuite.cli.CLIProg.java

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/*
 * $Id$
 * Copyright (C) 2006 Klaus Reimer <k@ailis.de>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

package de.ailis.wlandsuite.cli;

import gnu.getopt.Getopt;
import gnu.getopt.LongOpt;

import java.io.IOException;
import java.util.logging.Handler;
import java.util.logging.Logger;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import de.ailis.wlandsuite.utils.ResourceUtils;

/**
 * CLI program base class
 *
 * @author Klaus Reimer (k@ailis.de)
 * @version $Revision$
 */

public abstract class CLIProg {
    /** The logger */
    private static final Log log = LogFactory.getLog(CLIProg.class);

    /** The help text resource */
    private String help = "help/launcher.txt";

    /** The version information text resource */
    private final String version = "version.txt";

    /** The program name */
    private String progName = "wlandsuite";

    /** The long options of the program */
    private LongOpt[] longOpts = new LongOpt[0];

    /** Debug flag */
    private boolean debug = false;

    /**
     * Display command line help
     */

    private void help() {
        System.out.print(ResourceUtils.getText(this.help));
        System.exit(0);
    }

    /**
     * Display version information
     */

    private void version() {
        System.out.print(ResourceUtils.getText(this.version));
        System.exit(0);
    }

    /**
     * Outputs a usage error message
     *
     * @param message
     *            The error message
     */

    protected void wrongUsage(final String message) {
        log.error(message + "\nTry '" + this.progName + " --help' for more information.");
        System.exit(2);
    }

    /**
     * Process command line options
     *
     * @param args
     *            Command line arguments
     * @return The parameters which are left after processing the options
     */

    private String[] processOptions(final String[] args) {
        int c;
        LongOpt[] allLongOpts;
        String[] params;
        Getopt getopt;
        int i, p;
        StringBuilder shortOpts;

        // Setup long options
        allLongOpts = new LongOpt[3 + this.longOpts.length];
        allLongOpts[0] = new LongOpt("help", LongOpt.NO_ARGUMENT, null, 'h');
        allLongOpts[1] = new LongOpt("version", LongOpt.NO_ARGUMENT, null, 'V');
        allLongOpts[2] = new LongOpt("debug", LongOpt.NO_ARGUMENT, null, 'd');
        i = 3;
        for (final LongOpt longOpt : this.longOpts) {
            allLongOpts[i] = longOpt;
            i++;
        }

        // Build the shortOpts
        shortOpts = new StringBuilder();
        for (final LongOpt longOpt : allLongOpts) {
            shortOpts.append((char) longOpt.getVal());
            if (longOpt.getHasArg() == LongOpt.REQUIRED_ARGUMENT) {
                shortOpts.append(':');
            }
        }

        // Setup short options
        getopt = new Getopt(this.progName, args, shortOpts.toString(), allLongOpts);

        // Process options
        while ((c = getopt.getopt()) != -1) {
            switch (c) {
            case 'd':
                this.debug = true;
                break;
            case 'h':
                help();
                break;
            case 'V':
                version();
                break;
            default:
                processOption(c, getopt);
            }
        }

        // Generate parameters,
        params = new String[args.length - getopt.getOptind()];
        p = 0;
        for (i = getopt.getOptind(); i < args.length; i++) {
            params[p] = args[i];
            p++;
        }
        return params;
    }

    /**
     * Processes a single option.
     *
     * @param opt
     *            The option
     * @param getopt
     *            The Getopt object
     */

    protected void processOption(final int opt, final Getopt getopt) {
        // Empty
    }

    /**
     * The code which should be executed when the program is run
     *
     * @param params
     *            The parameters without the already processed options
     * @throws IOException
     *             When some file could not be read or written.
     */

    protected abstract void run(String[] params) throws IOException;

    /**
     * Runs the program
     *
     * @param args
     *            The command line arguments.
     */

    protected void start(final String[] args) {
        setupLogging();
        try {
            // Process command line arguments and run the program
            run(processOptions(args));
            log.info("Success");
        } catch (final Exception e) {
            if (this.debug || e.getMessage() == null) {
                e.printStackTrace();
                System.exit(1);
            } else {
                log.error(e.getMessage());
                System.exit(1);
            }
        }
    }

    /**
     * Setups loggings.
     */

    private void setupLogging() {
        Logger logger;

        logger = Logger.getLogger("");
        for (final Handler handler : logger.getHandlers()) {
            logger.removeHandler(handler);
        }
        logger.addHandler(new LogHandler(this.progName));
    }

    /**
     * Sets the help resource.
     *
     * @param help
     *            The help resource to set
     */

    public void setHelp(final String help) {
        this.help = help;
    }

    /**
     * Sets the long options.
     *
     * @param longOpts
     *            The long options to set
     */

    public void setLongOpts(final LongOpt[] longOpts) {
        this.longOpts = longOpts;
    }

    /**
     * Sets the program name
     *
     * @param progName
     *            The program name to set
     */

    public void setProgName(final String progName) {
        this.progName = progName;
    }
}