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

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Here is the source code for org.pepstock.jem.commands.util.Factory.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.IOException;
import java.io.StringWriter;
import java.net.URL;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.pepstock.jem.Job;
import org.pepstock.jem.PreJob;
import org.pepstock.jem.log.LogAppl;
import org.pepstock.jem.node.NodeMessage;

/**
 * Creates an PreJob object to put in JEM cluster.<br>
 * To do it, it must read the JCL content from a URL and normalize the format of job id. 
 * 
 * @author Andrea "Stock" Stocchero
 *
 */
public class Factory {

    //Max length for a long value. It uses numbers of digits of Long.MAX_VALUE
    private static final int LONG_LENGTH = String.valueOf(Long.MAX_VALUE).length();

    /**
     * Job id Format
     */
    public static final String JOBID_FORMAT = "{0,number}-{1,number}";

    /**
     * To avoid any instantiations
     */
    private Factory() {

    }

    /**
     * Creates the unique id for the job, normalizing generated id joined to started time stamp of job.<br>
     * it pads (on left) with '0' string representation of both id and timestamp
     * 
     * @param job job instance, needs to extract started timestamp 
     * @param id job id
     * @return job id in job format
     */
    public static String createJobId(Job job, long id) {
        StringBuilder sb = new StringBuilder();
        sb.append(StringUtils.leftPad(String.valueOf(id), LONG_LENGTH, "0")).append('-')
                .append(StringUtils.leftPad(String.valueOf(job.getSubmittedTime().getTime()), LONG_LENGTH, "0"));
        return sb.toString();
    }

    /**
     * Creates a PreJob instance, loading JCL content by URL
     *  
     * @param url JCL URL to load
     * @return PreJob instance to put on JEM cluster for submitting
     * @throws InstantiationException if IOException occurs
     */
    public static PreJob createPreJob(URL url) throws InstantiationException {
        try {
            // load JCL content from url
            String content = load(url);
            // create PreJob and load content
            PreJob job = new PreJob();
            job.setJclContent(content);
            return job;
        } catch (IOException e) {
            // debug
            LogAppl.getInstance().debug(e.getMessage(), e);
            throw new InstantiationException(e.getMessage());
        }
    }

    /**
     * Reads JCL content from URL and returns it in string format
     * 
     * @param url JCL URL
     * @return JCL content
     * @throws IOException if IOExcetion occurs during reading JCL file
     */
    private static String load(URL url) throws IOException {
        // checks if null. If yes, exception occurs
        if (url == null) {
            throw new IOException(NodeMessage.JEMC97E.toMessage().getFormattedMessage());
        }

        StringWriter sw = new StringWriter();
        IOUtils.copy(url.openStream(), sw);
        return sw.getBuffer().toString();
    }

}