org.deegree.commons.tools.CommandUtils.java Source code

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Here is the source code for org.deegree.commons.tools.CommandUtils.java

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//$HeadURL$
/*----------------------------------------------------------------------------
 This file is part of deegree, http://deegree.org/
 Copyright (C) 2001-2009 by:
 Department of Geography, University of Bonn
 and
 lat/lon GmbH
    
 This library is free software; you can redistribute it and/or modify it under
 the terms of the GNU Lesser General Public License as published by the Free
 Software Foundation; either version 2.1 of the License, or (at your option)
 any later version.
 This library 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 Lesser General Public License for more
 details.
 You should have received a copy of the GNU Lesser General Public License
 along with this library; if not, write to the Free Software Foundation, Inc.,
 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
    
 Contact information:
    
 lat/lon GmbH
 Aennchenstr. 19, 53177 Bonn
 Germany
 http://lat-lon.de/
    
 Department of Geography, University of Bonn
 Prof. Dr. Klaus Greve
 Postfach 1147, 53001 Bonn
 Germany
 http://www.geographie.uni-bonn.de/deegree/
    
 e-mail: info@deegree.org
 ----------------------------------------------------------------------------*/
package org.deegree.commons.tools;

import java.io.PrintWriter;
import java.io.StringWriter;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;

/**
 * This class contains some static convenience methods for commandline tools.
 * 
 * @author <a href="mailto:tonnhofer@lat-lon.de">Oliver Tonnhofer</a>
 * @author last edited by: $Author$
 * 
 * @version $Revision$, $Date$
 */
public class CommandUtils {

    /**
     * The width of the help text, for automatic text wrap.
     */
    public static int HELP_TEXT_WIDTH = 80;

    public static final String OPT_VERBOSE = "verbose";

    /**
     * Prints a help message for a apache commons-cli based command line tool and <b>terminates the programm</b>.
     * 
     * @param options
     *            the options to generate help/usage information for
     * @param toolName
     *            the name of the command line tool
     * @param helpMsg
     *            some further information
     * @param otherUsageInfo
     *            an optional string to append to the usage information (e.g. for additional arguments like input files)
     */
    public static void printHelp(Options options, String toolName, String helpMsg, String otherUsageInfo) {
        HelpFormatter formatter = new HelpFormatter();

        StringWriter helpWriter = new StringWriter();
        StringBuffer helpBuffer = helpWriter.getBuffer();
        PrintWriter helpPrintWriter = new PrintWriter(helpWriter);

        helpPrintWriter.println();

        if (helpMsg != null && helpMsg.length() != 0) {
            formatter.printWrapped(helpPrintWriter, HELP_TEXT_WIDTH, helpMsg);
            helpPrintWriter.println();
        }
        formatter.printUsage(helpPrintWriter, HELP_TEXT_WIDTH, toolName, options);
        if (otherUsageInfo != null) {
            helpBuffer.deleteCharAt(helpBuffer.length() - 1); // append additional arguments
            helpBuffer.append(' ').append(otherUsageInfo).append("\n");
        }

        helpBuffer.append("\n");
        formatter.printOptions(helpPrintWriter, HELP_TEXT_WIDTH, options, 3, 5);
        System.err.print(helpBuffer.toString());
        System.exit(1);
    }

    /**
     * Parse a command line argument as integer.
     * 
     * @param line
     *            the parsed command line
     * @param optName
     *            the option name
     * @param defaultValue
     *            the default value
     * @return the parsed integer argument or <code>defaulValue</code>, if the argument is missing
     * @throws ParseException
     *             if the argument is not a number
     */
    public static int getIntOption(CommandLine line, String optName, int defaultValue) throws ParseException {
        String stringValue = line.getOptionValue(optName);
        if (stringValue == null) {
            return defaultValue;
        }
        try {
            return Integer.parseInt(stringValue);
        } catch (NumberFormatException ex) {
            throw new ParseException(optName + " is not a number");
        }
    }

    /**
     * Parse a command line argument as float.
     * 
     * @param line
     *            the parsed command line
     * @param optName
     *            the option name
     * @param defaultValue
     *            the default value
     * @return the parsed float argument or <code>defaulValue</code>, if the argument is missing
     * @throws ParseException
     *             if the argument is not a number
     */
    public static float getFloatOption(CommandLine line, String optName, float defaultValue) throws ParseException {
        String stringValue = line.getOptionValue(optName);
        if (stringValue == null) {
            return defaultValue;
        }
        try {
            return Float.parseFloat(stringValue);
        } catch (NumberFormatException ex) {
            throw new ParseException(optName + " is not a number");
        }
    }

    /**
     * @param options
     */
    public static void addDefaultOptions(Options options) {
        options.addOption("v", OPT_VERBOSE, false, "be verbose on errors");
        options.addOption("?", "help", false, "print (this) usage information");
    }
}