RootFolder.java
/*
* Copyright (C) 2016 essobedo.
*
* This 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 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package com.github.essobedo.appma.core.io;
import java.io.File;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
/**
* Class allowing to get the root folder that contains a given class.
*
* @author Nicolas Filotto (nicolas.filotto@gmail.com)
* @version $Id$
* @since 1.0
*/
public final class RootFolder {
/**
* The class for which we want to know its parent folder.
*/
private final Class<?> clazz;
/**
* Constructs a {@code RootFolder} with the specified class.
* @param clazz the class for which we want to know its parent folder.
*/
public RootFolder(final Class<?> clazz) {
this.clazz = clazz;
}
/**
* Gives the folder that contains the class. In case the class is located in a folder
* it will give the folder from which the packages start. In case the class is located
* in a jar file it will give the folder that contains the jar file.
* @return the {@code File} corresponding to the folder that contains the class.
*/
public File getLocation() {
final String name = clazz.getName();
final String resource = String.format("/%s.class", name.replace('.', '/'));
final URL url = clazz.getResource(resource);
if (url == null) {
throw new IllegalStateException(String.format("Cannot locate the class '%s'", name));
}
try {
if ("file".equals(url.getProtocol())) {
final String urlStr = url.toString();
final String root = urlStr.substring(0, urlStr.length() - resource.length() + 1);
return new File(new URI(root));
} else if ("jar".equals(url.getProtocol())) {
String urlStr = url.getPath();
int index = urlStr.lastIndexOf('!');
urlStr = urlStr.substring(0, index);
index = urlStr.lastIndexOf('/');
final String root = urlStr.substring(0, index + 1);
return new File(new URI(root));
}
} catch (URISyntaxException e) {
throw new IllegalStateException(String.format("Could not manage the path '%s'", url), e);
}
throw new IllegalStateException(String.format("Cannot manage the protocol '%s'", url.getProtocol()));
}
}