uk.org.retep.util.app.ApplicationUtil Maven / Gradle / Ivy
/*
* Copyright (c) 1998-2007, Peter T Mount
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the retep.org.uk nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
*
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package uk.org.retep.util.app;
import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
/**
*
* @author peter
*/
public final class ApplicationUtil
{
private ApplicationUtil()
{
}
/**
* Return the jar file URL containing the given class
*
* @param clazz Class who's jar URL is required
* @return URL
* @throws MalformedURLException on error
*/
public static URL getJarURL( Class clazz )
throws MalformedURLException
{
URL classURL = clazz.getResource( clazz.getSimpleName() + ".class" );
if( classURL==null )
{
return null;
}
String path = classURL.toString();
int i=path.indexOf('!');
if( i>-1 )
{
path=path.substring( 0, i );
}
if( path.startsWith( "jar:" ) )
{
path = path.substring( 4 );
}
return new URL( path );
}
/**
* Return a java.io.File representing the jar containing the supplied Class.
* Note This only works for applications
* @param clazz Class
* @return File containing the Class, null if not resolvable
*/
public static File getJarFile( Class clazz )
{
try
{
URL jarURL = getJarURL( clazz );
if( jarURL!=null )
{
return new File( jarURL.getPath() ).getAbsoluteFile();
}
return null;
}
catch( MalformedURLException ex )
{
ex.printStackTrace();
return null;
}
}
/**
* Return a java.io.File representing the directory containing the jar
* containing the supplied Class - in otherwords the application's
* installation directory.
*
* Note This only works for applications
* @param clazz Class
* @return File representing the applications installation directory or
* null if not resolvable
*/
public static File getApplicationDirectory( Class clazz )
{
File jarFile = getJarFile( clazz );
if( jarFile==null )
{
return null;
}
jarFile = jarFile.getParentFile();
// If the directory is lib then return it's parent
if( jarFile!=null && "lib".equals( jarFile.getName() ) )
{
jarFile = jarFile.getParentFile();
}
return jarFile;
}
/**
* Return a java.net.URL representing the directory containing the jar
* containing the supplied Class - in otherwords the application's
* installation directory.
*
* Note This only works for applications
* @param clazz Class
* @return URL representing the applications installation directory or
* null if not resolvable
*/
public static URL getApplicationDirectoryURL( Class clazz )
{
File dir = getApplicationDirectory( clazz );
try
{
return dir==null ? null : dir.toURI().toURL();
}
catch( MalformedURLException ex )
{
return null;
}
}
}