Locating files by path or URL
/*
* JBoss, Home of Professional Open Source
* Copyright 2006, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags.
* See the copyright.txt in the distribution for a
* full listing of individual contributors.
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License, v. 2.1.
* This program is distributed in the hope that it will be useful, but WITHOUT A
* 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,
* v.2.1 along with this distribution; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA.
*
* (C) 2005-2006,
* @author JBoss Inc.
*/
/*
* Copyright (C) 1998, 1999, 2000, 2001,
*
* Arjuna Solutions Limited,
* Newcastle upon Tyne,
* Tyne and Wear,
* UK.
*
* $Id: FileLocator.java 2342 2006-03-30 13:06:17Z $
*/
import java.io.File;
import java.net.URL;
import java.io.FileNotFoundException;
import java.net.MalformedURLException;
/**
* The FileLocator class provides a common method for locating files.
* If not passed an absolute filename (starting with the string "abs://"),
* it searches for the file in the order:
* in the directory specified by the system property user.dir
* in the directory specified by the system property user.home
* in the directory specified by the system property java.home
* using the getResource() method
*
* @author Julian Coleman
* @version $Id: FileLocator.java 2342 2006-03-30 13:06:17Z $
* @since JTS 3.0.
*/
public class FileLocator
{
/**
* Locate the specific file.
* Return the (URL decoded) abolute pathname to the file or null.
*/
public static String locateFile (String findFile) throws FileNotFoundException
{
URL url;
String fullPathName;
StringBuffer decodedPathName;
int pos, len, start;
if (findFile == null)
throw new FileNotFoundException("locateFile: null file name");
if (findFile.startsWith(absolutePath))
return findFile.substring(absolutePath.length());
if ((fullPathName = locateByProperty(findFile)) != null)
return fullPathName;
if ((url = locateByResource(findFile)) != null)
{
/*
* The URL that we receive from getResource /might/ have ' '
* (space) characters converted to "%20" strings. However,
* it doesn't have other URL encoding (e.g '+' characters are
* kept intact), so we'll just convert all "%20" strings to
* ' ' characters and hope for the best.
*/
fullPathName = url.getFile();
pos = 0;
len = fullPathName.length();
start = 0;
decodedPathName = new StringBuffer();
while ((pos = fullPathName.indexOf(pct20, start)) != -1) {
decodedPathName.append(fullPathName.substring(start, pos));
decodedPathName.append(' ');
start = pos + pct20len;
}
if (start < len)
decodedPathName.append(fullPathName.substring(start, len));
fullPathName=decodedPathName.toString();
if (platformIsWindows())
fullPathName = fullPathName.substring(1, fullPathName.length());
return fullPathName;
}
throw new FileNotFoundException("locateFile: file not found: " + findFile);
}
/**
* Locate the specific file.
* Return the file name in URL form or null.
*/
public static URL locateURL (String findFile) throws FileNotFoundException
{
URL url;
String fullPathName;
if (findFile == null)
throw new FileNotFoundException("locateURL: null file name");
try {
if (findFile.startsWith(absolutePath))
{
return (new URL("file:/" + findFile.substring(absolutePath.length())));
}
if ((fullPathName = locateByProperty(findFile)) != null)
{
if(platformIsWindows())
url = new URL("file:/" + fullPathName);
else
url = new URL("file:" + fullPathName);
return url;
}
//TODO: TR: used for testing: return new URL(findFile);
}
catch (MalformedURLException e)
{
System.err.println("locateURL: URL creation problem");
throw new FileNotFoundException("locateURL: URL creation problem");
}
if ((url = locateByResource(findFile)) != null)
return url;
throw new FileNotFoundException("locateURL: file not found: " + findFile);
}
/**
* Search for a file using the properties: user.dir, user.home, java.home
* Returns absolute path name or null.
*/
private static synchronized String locateByProperty(String findFile)
{
String fullPathName = null;
String dir = null;
File f = null;
if (findFile == null)
return null;
try
{
// System.err.println("Searching in user.dir for: " + findFile);
dir = System.getProperty("user.dir");
if (dir != null) {
fullPathName = dir + File.separatorChar + findFile;
f = new File(fullPathName);
}
if (f != null && f.exists())
{
// System.err.println("Found in user.dir");
return fullPathName;
}
dir = System.getProperty("user.home");
if (dir != null) {
fullPathName = dir + File.separatorChar + findFile;
f = new File(fullPathName);
}
if (f != null && f.exists())
{
// System.err.println("Found in user.home");
return fullPathName;
}
dir = System.getProperty("java.home");
if (dir != null) {
fullPathName = dir + File.separatorChar + findFile;
f = new File(fullPathName);
}
if (f != null && f.exists())
{
// System.err.println("Found in java.home");
return fullPathName;
}
}
catch (Exception e)
{
return null;
}
return null;
}
/**
* Search for a file using the properties: user.dir, user.home, java.home
* Returns URL or null.
*/
private static URL locateByResource(String findFile)
{
ClassLoader loader = Thread.currentThread().getContextClassLoader();
URL url = loader.getResource(findFile);
if (url == null)
{
url = FileLocator.class.getResource("/" + findFile);
}
// System.err.println("Search succeeded via getResource()");
return url;
}
/*
* Check the file separator to see if we're on a Windows platform.
*
* @return boolean True if the platform is Windows, false otherwise.
*/
private static boolean platformIsWindows()
{
if(File.separatorChar == '\\')
{
return true;
}
return false;
}
private static final String absolutePath = "abs://";
private static final String pct20 = "%20";
private static final int pct20len = 3;
}
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