org.pepstock.jem.commands.util.ArgumentsParser.java Source code

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Here is the source code for org.pepstock.jem.commands.util.ArgumentsParser.java

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/**
JEM, the BEE - Job Entry Manager, the Batch Execution Environment
Copyright (C) 2012-2015   Andrea "Stock" Stocchero
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
any later version.
    
This program 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 General Public License for more details.
    
You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package org.pepstock.jem.commands.util;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.commons.cli.PosixParser;
import org.pepstock.jem.log.LogAppl;
import org.pepstock.jem.node.NodeMessage;

/**
 * Utility class to parse the arguments of command line
 * 
 * @author Andrea "Stock" Stocchero
 * 
 */
public class ArgumentsParser {

    private String commandLine = null;

    private final List<Option> options = new ArrayList<Option>();

    /**
     * Constructor with command line (used only on help message) and all
     * options.
     * 
     * @param commandLine command line
     * @param options options to check
     * 
     */
    public ArgumentsParser(String commandLine) {
        this.commandLine = commandLine;
    }

    /**
     * Returns the commnd line
     * 
     * @return the commandLine
     */
    public String getCommandLine() {
        return commandLine;
    }

    /**
     * Returns all options
     * 
     * @return the options
     */
    public List<Option> getOptions() {
        return options;
    }

    /**
     * Parses all arguments passed by command line.<br>
     * Creates all possible arguments with explanation to show in case of error.
     * 
     * @param args arguments of main method
     * @return properties with all arguments
     * @throws ParseException if same args are missing or wrong
     */
    public Properties parseArg(String[] args) throws ParseException {

        // creates all possible commands options

        // -help options
        Option help = new Option("help", "print this message");

        // loads all created options
        Options allOptions = new Options();
        allOptions.addOption(help);

        for (Option opt : options) {
            allOptions.addOption(opt);
        }
        // creates command line parser
        CommandLineParser parser = new PosixParser();
        CommandLine line;
        try {
            Properties properties = new Properties();
            // parses line
            line = parser.parse(allOptions, args);
            // checks if asked for help. If yes, prints help
            if ((line.getOptions().length == 1) && line.hasOption("help")) {
                StringWriter writer = new StringWriter();
                HelpFormatter formatter = new HelpFormatter();
                formatter.printHelp(new PrintWriter(writer), HelpFormatter.DEFAULT_WIDTH, getCommandLine(), "",
                        allOptions, HelpFormatter.DEFAULT_LEFT_PAD, HelpFormatter.DEFAULT_DESC_PAD, "");
                LogAppl.getInstance().emit(NodeMessage.JEMC056I, writer.getBuffer());
            } else {
                Option[] optionsLine = line.getOptions();
                for (int i = 0; i < optionsLine.length; i++) {
                    String key = optionsLine[i].getArgName();
                    String value;
                    // to avoid null pointer exception in case of option line
                    // with no arg
                    if (optionsLine[i].hasArg()) {
                        value = optionsLine[i].getValue();
                    } else {
                        value = "";
                    }

                    properties.setProperty(key, value);
                }
            }
            return properties;
        } catch (ParseException e) {
            // if exception, returns -help command
            // because if is here has found an error on arguments
            StringWriter writer = new StringWriter();
            HelpFormatter formatter = new HelpFormatter();
            formatter.printHelp(new PrintWriter(writer), HelpFormatter.DEFAULT_WIDTH, getCommandLine(), "",
                    allOptions, HelpFormatter.DEFAULT_LEFT_PAD, HelpFormatter.DEFAULT_DESC_PAD, "");
            LogAppl.getInstance().emit(NodeMessage.JEMC056I, writer.getBuffer());
            throw e;
        }

    }

}