infinispan.com.mchange.v2.io.FileUtils Maven / Gradle / Ivy
/*
* Distributed as part of mchange-commons-java 0.2.7
*
* Copyright (C) 2014 Machinery For Change, Inc.
*
* Author: Steve Waldman
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of EITHER:
*
* 1) The GNU Lesser General Public License (LGPL), version 2.1, as
* published by the Free Software Foundation
*
* OR
*
* 2) The Eclipse Public License (EPL), version 1.0
*
* You may choose which license to accept if you wish to redistribute
* or modify this work. You may offer derivatives of this work
* under the license you have chosen, or you may provide the same
* choice of license which you have been offered here.
*
* 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.
*
* You should have received copies of both LGPL v2.1 and EPL v1.0
* along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
* If not, the text of these licenses are currently available at
*
* LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php
*
*/
package com.mchange.v2.io;
import java.io.*;
public final class FileUtils
{
public static File findRelativeToParent(File parentDir, File file) throws IOException
{
String parentPath = parentDir.getPath();
String filePath = file.getPath();
if (! filePath.startsWith( parentPath ) )
throw new IllegalArgumentException( filePath + " is not a child of " + parentPath + " [no transformations or canonicalizations tried]" );
String maybeRelative = filePath.substring( parentPath.length() );
File out = new File( maybeRelative );
if ( out.isAbsolute() )
out = new File( out.getPath().substring(1) );
return out;
}
public static long diskSpaceUsed( File maybeDir ) throws IOException
{
long sum = 0;
for (FileIterator ff = DirectoryDescentUtils.depthFirstEagerDescent( maybeDir ); ff.hasNext();)
{
File addMe = ff.nextFile();
//System.err.println("diskSpacedUsed() -- checking: " + addMe);
if (! addMe.isFile())
continue;
sum += addMe.length();
}
return sum;
}
public static void touchExisting( File file ) throws IOException
{
if ( file.exists() )
unguardedTouch( file );
}
public static void touch( File file ) throws IOException
{
if (! file.exists() )
createEmpty( file );
unguardedTouch( file );
}
public static void createEmpty( File file ) throws IOException
{
RandomAccessFile raf = null;
try
{
raf = new RandomAccessFile( file, "rws" );
raf.setLength( 0 );
}
finally
{
try { if (raf != null) raf.close(); }
catch ( IOException e )
{ e.printStackTrace(); }
}
}
private static void unguardedTouch( File file ) throws IOException
{ file.setLastModified( System.currentTimeMillis() ); }
private FileUtils()
{}
}