es.emergya.tools.JarSearcher.java Source code

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Here is the source code for es.emergya.tools.JarSearcher.java

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/*
 * Copyright (C) 2010, Emergya (http://www.emergya.es)
 *
 * @author <a href="mailto:jlrodriguez@emergya.es">Juan Lus Rodrguez</a>
 * @author <a href="mailto:marias@emergya.es">Mara Arias</a>
 *
 * This file is part of GoFleet
 *
 * This software 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 2 of the License, or
 * (at your option) any later version.
 *
 * This software 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 library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * As a special exception, if you link this library with other files to
 * produce an executable, this library does not by itself cause the
 * resulting executable to be covered by the GNU General Public License.
 * This exception does not however invalidate any other reasons why the
 * executable file might be covered by the GNU General Public License.
 */
package es.emergya.tools;

import java.io.File;
import java.net.URL;

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

/**
 * Returns the path in which the .jar-Archive which contains this class is
 * located
 * 
 * @author nigjo
 */
public class JarSearcher {
    private final static Log LOG = LogFactory.getLog(JarSearcher.class);
    private Class<? extends Object> searchClass;

    public JarSearcher() {
    }

    public static File getJar(Object obj) {
        JarSearcher searcher = new JarSearcher();

        searcher.setClass(obj.getClass());

        return searcher.findJar();
    }

    public static File getJar(Class<?> clazz) {
        JarSearcher searcher = new JarSearcher();
        searcher.setClass(clazz);
        return searcher.findJar();
    }

    /**
     * 
     * Returns the File Object of the .jar file
     * 
     * @return <code>null</code> if this class isn't stored in a .jar file
     */
    private File findJar() {
        String klasse = this.getClassURL().getFile();

        if (klasse.indexOf(".jar!") >= 0) {
            String jar = klasse.substring(0, klasse.indexOf(".jar!") + 4);

            return new File(jar);
        }

        // no jar found
        return null;
    }

    private URL getClassURL() {
        String name = this.searchClass.getName();

        name = name.replaceAll("\\.", "/");

        return this.searchClass.getClassLoader().getResource(name + ".class");
    }

    private void setClass(Class<? extends Object> toSearch) {
        this.searchClass = toSearch;
    }

    /**
     * Returns the path to the .jar-Datei containing the class of the object
     * given
     * 
     * @param obj
     * @return <code>null</code> if the class of the object is not in a .jar
     *         file
     */
    public static File getJarDirectory(Object obj) {
        // Search for .jar file
        File jar = JarSearcher.getJar(obj);
        if (jar != null)
            // .jar found
            return jar.getParentFile();
        // ... not found
        return null;
    }

    public static File getJarDirectory(Class<?> clazz) {
        File jar = JarSearcher.getJar(clazz);
        if (jar != null) {
            // .jar found
            if (JarSearcher.LOG.isTraceEnabled())
                JarSearcher.LOG.trace("getJarDirectory: " + jar.getParentFile().getAbsolutePath());
            return jar.getParentFile();
        }
        // ... not found
        return null;
    }
}