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apache / maven-shared-utils / refs/heads/MSHARED-826 / . / src / main / java / org / apache / maven / shared / utils / io / FileUtils.java
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package org.apache.maven.shared.utils.io;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
import org.apache.maven.shared.utils.Os;
import org.apache.maven.shared.utils.StringUtils;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.WillClose;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.net.URL;
import java.nio.channels.FileChannel;
import java.nio.file.Files;
import java.security.SecureRandom;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Random;
/**
* This class provides basic facilities for manipulating files and file paths.
* <p/>
* <h3>Path-related methods</h3>
* <p/>
* <p>Methods exist to retrieve the components of a typical file path. For example
* <code>/www/hosted/mysite/index.html</code>, can be broken into:
* <ul>
* <li><code>/www/hosted/mysite/index</code> -- retrievable through {@link #removeExtension}</li>
* <li><code>html</code> -- retrievable through {@link #getExtension}</li>
* </ul>
* </p>
* <p/>
* <h3>File-related methods</h3>
* <p/>
* There are methods to create a {@link #toFile File from a URL}, copy a
* copy a {@link #copyFile File to another File},
* copy a {@link #copyURLToFile URL's contents to a File},
* as well as methods to {@link #deleteDirectory(File) delete} and {@link #cleanDirectory(File)
* clean} a directory.
* </p>
* <p/>
* Common {@link java.io.File} manipulation routines.
* <p/>
* Taken from the commons-utils repo.
* Also code from Alexandria's FileUtils.
* And from Avalon Excalibur's IO.
* And from Ant.
*
* @author <a href="mailto:burton@relativity.yi.org">Kevin A. Burton</A>
* @author <a href="mailto:sanders@apache.org">Scott Sanders</a>
* @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a>
* @author <a href="mailto:Christoph.Reck@dlr.de">Christoph.Reck</a>
* @author <a href="mailto:peter@apache.org">Peter Donald</a>
* @author <a href="mailto:jefft@apache.org">Jeff Turner</a>
*/
public class FileUtils
{
/**
* protected constructor.
*/
protected FileUtils()
{
// This is a utility class. Normally dont instantiate
}
/**
* The number of bytes in a kilobyte.
*/
private static final int ONE_KB = 1024;
/**
* The number of bytes in a megabyte.
*/
private static final int ONE_MB = ONE_KB * ONE_KB;
/**
* The file copy buffer size (30 MB)
*/
private static final long FILE_COPY_BUFFER_SIZE = ONE_MB * 30;
/**
* Non-valid Characters for naming files, folders under Windows: <code>":", "*", "?", "\"", "<", ">", "|"</code>
*
* @see <a href="http://support.microsoft.com/?scid=kb%3Ben-us%3B177506&x=12&y=13">
* http://support.microsoft.com/?scid=kb%3Ben-us%3B177506&x=12&y=13</a>
*/
private static final String[] INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME = { ":", "*", "?", "\"", "<", ">", "|" };
/**
* @return the default excludes pattern
* @see DirectoryScanner#DEFAULTEXCLUDES
*/
@Nonnull public static String[] getDefaultExcludes()
{
return DirectoryScanner.DEFAULTEXCLUDES;
}
/**
* @return the default excludes pattern as list.
* @see #getDefaultExcludes()
*/
@Nonnull public static List<String> getDefaultExcludesAsList()
{
return Arrays.asList( getDefaultExcludes() );
}
/**
* @return the default excludes pattern as comma separated string.
* @see DirectoryScanner#DEFAULTEXCLUDES
* @see StringUtils#join(Object[], String)
*/
@Nonnull public static String getDefaultExcludesAsString()
{
return StringUtils.join( DirectoryScanner.DEFAULTEXCLUDES, "," );
}
/**
* Returns the directory path portion of a file specification string.
* Matches the equally named unix command.
*
* @param filename the file path
* @return The directory portion excluding the ending file separator.
*/
@Nonnull public static String dirname( @Nonnull String filename )
{
int i = filename.lastIndexOf( File.separator );
return ( i >= 0 ? filename.substring( 0, i ) : "" );
}
/**
* Returns the filename portion of a file specification string.
*
* @param filename the file path
* @return The filename string with extension.
*/
@Nonnull public static String filename( @Nonnull String filename )
{
int i = filename.lastIndexOf( File.separator );
return ( i >= 0 ? filename.substring( i + 1 ) : filename );
}
/**
* Returns the extension portion of a file specification string.
* This everything after the last dot '.' in the filename (NOT including
* the dot).
*
* @param filename the file path
* @return the extension of the file
*/
@Nonnull public static String extension( @Nonnull String filename )
{
// Ensure the last dot is after the last file separator
int lastSep = filename.lastIndexOf( File.separatorChar );
int lastDot;
if ( lastSep < 0 )
{
lastDot = filename.lastIndexOf( '.' );
}
else
{
lastDot = filename.substring( lastSep + 1 ).lastIndexOf( '.' );
if ( lastDot >= 0 )
{
lastDot += lastSep + 1;
}
}
if ( lastDot >= 0 && lastDot > lastSep )
{
return filename.substring( lastDot + 1 );
}
return "";
}
/**
* Check if a file exits.
*
* @param fileName the file path.
* @return true if file exists.
*/
public static boolean fileExists( @Nonnull String fileName )
{
File file = new File( fileName );
return file.exists();
}
/**
* Note: the file content is read with platform encoding.
*
* @param file the file path
* @return the file content using the platform encoding.
* @throws IOException if any
*/
@Nonnull public static String fileRead( @Nonnull String file )
throws IOException
{
return fileRead( file, null );
}
/**
* @param file the file path
* @param encoding the wanted encoding
* @return the file content using the specified encoding.
* @throws IOException if any
*/
@Nonnull private static String fileRead( @Nonnull String file, @Nullable String encoding )
throws IOException
{
return fileRead( new File( file ), encoding );
}
/**
* Note: the file content is read with platform encoding
*
* @param file the file path
* @return the file content using the platform encoding.
* @throws IOException if any
*/
@Nonnull public static String fileRead( @Nonnull File file )
throws IOException
{
return fileRead( file, null );
}
/**
* @param file the file path
* @param encoding the wanted encoding
* @return the file content using the specified encoding.
* @throws IOException if any
*/
@Nonnull public static String fileRead( @Nonnull File file, @Nullable String encoding )
throws IOException
{
StringBuilder buf = new StringBuilder();
try ( Reader reader = getReader( file, encoding ) )
{
int count;
char[] b = new char[512];
while ( ( count = reader.read( b ) ) >= 0 ) // blocking read
{
buf.append( b, 0, count );
}
}
return buf.toString();
}
private static Reader getReader( @Nonnull File file, @Nullable String encoding ) throws IOException
{
if ( encoding != null )
{
return new InputStreamReader( new FileInputStream( file ), encoding );
}
else
{
return new InputStreamReader( new FileInputStream( file ) );
}
}
/**
* @param file the file path
* @return the file content lines as String[] using the systems default encoding.
* An empty List if the file didn't exist.
* @throws IOException in case of failure.
*/
@Nonnull public static String[] fileReadArray( @Nonnull File file )
throws IOException
{
List<String> lines = loadFile( file );
return lines.toArray( new String[lines.size()] );
}
/**
* Appends data to a file. The file will be created if it does not exist.
* Note: the data is written with platform encoding
*
* @param fileName The path of the file to write.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileAppend( @Nonnull String fileName, @Nonnull String data )
throws IOException
{
fileAppend( fileName, null, data );
}
/**
* Appends data to a file. The file will be created if it does not exist.
*
* @param fileName The path of the file to write.
* @param encoding The encoding of the file.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileAppend( @Nonnull String fileName, @Nullable String encoding, @Nonnull String data )
throws IOException
{
try ( FileOutputStream out = new FileOutputStream( fileName, true ) )
{
if ( encoding != null )
{
out.write( data.getBytes( encoding ) );
}
else
{
out.write( data.getBytes() );
}
}
}
/**
* Writes data to a file. The file will be created if it does not exist.
* Note: the data is written with platform encoding
*
* @param fileName The path of the file to write.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileWrite( @Nonnull String fileName, @Nonnull String data )
throws IOException
{
fileWrite( fileName, null, data );
}
/**
* Writes data to a file. The file will be created if it does not exist.
*
* @param fileName The path of the file to write.
* @param encoding The encoding of the file.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileWrite( @Nonnull String fileName, @Nullable String encoding, @Nonnull String data )
throws IOException
{
File file = new File( fileName );
fileWrite( file, encoding, data );
}
/**
* Writes data to a file. The file will be created if it does not exist.
*
* @param file The path of the file to write.
* @param encoding The encoding of the file.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileWrite( @Nonnull File file, @Nullable String encoding, @Nonnull String data )
throws IOException
{
try ( Writer writer = getWriter( file, encoding ) )
{
writer.write( data );
}
}
private static Writer getWriter( @Nonnull File file, @Nullable String encoding ) throws IOException
{
if ( encoding != null )
{
return new OutputStreamWriter( new FileOutputStream( file ), encoding );
}
else
{
return new OutputStreamWriter( new FileOutputStream( file ) );
}
}
/**
* Writes String array data to a file in the systems default encoding.
* The file will be created if it does not exist.
*
* @param file The path of the file to write.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileWriteArray( @Nonnull File file, @Nullable String... data )
throws IOException
{
fileWriteArray( file, null, data );
}
/**
* Writes String array data to a file. The file will be created if it does not exist.
*
* @param file The path of the file to write.
* @param encoding The encoding of the file.
* @param data The content to write to the file.
* @throws IOException if any
*/
public static void fileWriteArray( @Nonnull File file, @Nullable String encoding, @Nullable String... data )
throws IOException
{
try ( Writer writer = getWriter( file, encoding ) )
{
for ( int i = 0; data != null && i < data.length; i++ )
{
writer.write( data[i] );
if ( i < data.length )
{
writer.write( "\n" );
}
}
}
}
/**
* Deletes a file.
*
* @param fileName The path of the file to delete.
*/
public static void fileDelete( @Nonnull String fileName )
{
File file = new File( fileName );
//noinspection ResultOfMethodCallIgnored
deleteLegacyStyle( file );
}
/**
* Given a directory and an array of extensions return an array of compliant files.
* <p/>
* The given extensions should be like "java" and not like ".java"
*
* @param directory The path of the directory.
* @param extensions an array of expected extensions.
* @return An array of files for the wanted extensions.
*/
public static String[] getFilesFromExtension( @Nonnull String directory, @Nonnull String... extensions )
{
List<String> files = new ArrayList<>();
File currentDir = new File( directory );
String[] unknownFiles = currentDir.list();
if ( unknownFiles == null )
{
return new String[0];
}
for ( String unknownFile : unknownFiles )
{
String currentFileName = directory + File.separator + unknownFile;
File currentFile = new File( currentFileName );
if ( currentFile.isDirectory() )
{
// ignore all CVS directories...
if ( currentFile.getName().equals( "CVS" ) )
{
continue;
}
// ok... transverse into this directory and get all the files... then combine
// them with the current list.
String[] fetchFiles = getFilesFromExtension( currentFileName, extensions );
files = blendFilesToList( files, fetchFiles );
}
else
{
// ok... add the file
String add = currentFile.getAbsolutePath();
if ( isValidFile( add, extensions ) )
{
files.add( add );
}
}
}
// ok... move the Vector into the files list...
String[] foundFiles = new String[files.size()];
files.toArray( foundFiles );
return foundFiles;
}
/**
* Private helper method for getFilesFromExtension()
*/
@Nonnull private static List<String> blendFilesToList( @Nonnull List<String> v, @Nonnull String... files )
{
Collections.addAll( v, files );
return v;
}
/**
* Checks to see if a file is of a particular type(s).
* Note that if the file does not have an extension, an empty string
* (&quot;&quot;) is matched for.
*/
private static boolean isValidFile( @Nonnull String file, @Nonnull String... extensions )
{
String extension = extension( file );
// ok.. now that we have the "extension" go through the current know
// excepted extensions and determine if this one is OK.
for ( String extension1 : extensions )
{
if ( extension1.equals( extension ) )
{
return true;
}
}
return false;
}
/**
* Simple way to make a directory
*
* @param dir the directory to create
* @throws IllegalArgumentException if the dir contains illegal Windows characters under Windows OS.
* @see #INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME
*/
public static void mkdir( @Nonnull String dir )
{
File file = new File( dir );
if ( Os.isFamily( Os.FAMILY_WINDOWS ) && !isValidWindowsFileName( file ) )
{
throw new IllegalArgumentException(
"The file (" + dir + ") cannot contain any of the following characters: \n" + StringUtils.join(
INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME, " " ) );
}
if ( !file.exists() )
{
//noinspection ResultOfMethodCallIgnored
file.mkdirs();
}
}
/**
* Compare the contents of two files to determine if they are equal or not.
*
* @param file1 the first file
* @param file2 the second file
* @return true if the content of the files are equal or they both don't exist, false otherwise
* @throws IOException if any
*/
public static boolean contentEquals( @Nonnull final File file1, @Nonnull final File file2 )
throws IOException
{
final boolean file1Exists = file1.exists();
if ( file1Exists != file2.exists() )
{
return false;
}
if ( !file1Exists )
{
// two not existing files are equal
return true;
}
if ( file1.isDirectory() || file2.isDirectory() )
{
// don't want to compare directory contents
return false;
}
try ( InputStream input1 = new FileInputStream( file1 );
InputStream input2 = new FileInputStream( file2 ) )
{
return IOUtil.contentEquals( input1, input2 );
}
}
/**
* Convert from a <code>URL</code> to a <code>File</code>.
*
* @param url File URL.
* @return The equivalent <code>File</code> object, or <code>null</code> if the URL's protocol
* is not <code>file</code>
*/
@Nullable public static File toFile( @Nullable final URL url )
{
if ( url == null || !url.getProtocol().equalsIgnoreCase( "file" ) )
{
return null;
}
String filename = url.getFile().replace( '/', File.separatorChar );
int pos = -1;
while ( ( pos = filename.indexOf( '%', pos + 1 ) ) >= 0 )
{
if ( pos + 2 < filename.length() )
{
String hexStr = filename.substring( pos + 1, pos + 3 );
char ch = (char) Integer.parseInt( hexStr, 16 );
filename = filename.substring( 0, pos ) + ch + filename.substring( pos + 3 );
}
}
return new File( filename );
}
/**
* Convert the array of Files into a list of URLs.
*
* @param files the array of files
* @return the array of URLs
* @throws IOException if an error occurs
*/
@Nonnull public static URL[] toURLs( @Nonnull final File... files )
throws IOException
{
final URL[] urls = new URL[files.length];
for ( int i = 0; i < urls.length; i++ )
{
urls[i] = files[i].toURI().toURL();
}
return urls;
}
/**
* Remove extension from filename.
* ie
* <pre>
* foo.txt --> foo
* a\b\c.jpg --> a\b\c
* a\b\c --> a\b\c
* </pre>
*
* @param filename the path of the file
* @return the filename minus extension
*/
@Nonnull public static String removeExtension( @Nonnull final String filename )
{
String ext = extension( filename );
if ( "".equals( ext ) )
{
return filename;
}
final int index = filename.lastIndexOf( ext ) - 1;
return filename.substring( 0, index );
}
/**
* Get extension from filename.
* ie
* <pre>
* foo.txt --> "txt"
* a\b\c.jpg --> "jpg"
* a\b\c --> ""
* </pre>
*
* @param filename the path of the file
* @return the extension of filename or "" if none
*/
@Nonnull public static String getExtension( @Nonnull final String filename )
{
return extension( filename );
}
/**
* Copy file from source to destination. If <code>destinationDirectory</code> does not exist, it
* (and any parent directories) will be created. If a file <code>source</code> in
* <code>destinationDirectory</code> exists, it will be overwritten.
*
* @param source An existing <code>File</code> to copy.
* @param destinationDirectory A directory to copy <code>source</code> into.
* @throws java.io.FileNotFoundException if <code>source</code> isn't a normal file.
* @throws IllegalArgumentException if <code>destinationDirectory</code> isn't a directory.
* @throws IOException if <code>source</code> does not exist, the file in
* <code>destinationDirectory</code> cannot be written to, or an IO error
* occurs during copying.
*/
public static void copyFileToDirectory( @Nonnull final File source, @Nonnull final File destinationDirectory )
throws IOException
{
if ( destinationDirectory.exists() && !destinationDirectory.isDirectory() )
{
throw new IllegalArgumentException( "Destination is not a directory" );
}
copyFile( source, new File( destinationDirectory, source.getName() ) );
}
/**
* Copy file from source to destination only if source is newer than the target file.
* If <code>destinationDirectory</code> does not exist, it
* (and any parent directories) will be created. If a file <code>source</code> in
* <code>destinationDirectory</code> exists, it will be overwritten.
*
* @param source An existing <code>File</code> to copy.
* @param destinationDirectory A directory to copy <code>source</code> into.
* @throws java.io.FileNotFoundException if <code>source</code> isn't a normal file.
* @throws IllegalArgumentException if <code>destinationDirectory</code> isn't a directory.
* @throws IOException if <code>source</code> does not exist, the file in
* <code>destinationDirectory</code> cannot be written to, or an IO error
* occurs during copying.
*/
private static void copyFileToDirectoryIfModified( @Nonnull final File source,
@Nonnull final File destinationDirectory )
throws IOException
{
if ( destinationDirectory.exists() && !destinationDirectory.isDirectory() )
{
throw new IllegalArgumentException( "Destination is not a directory" );
}
copyFileIfModified( source, new File( destinationDirectory, source.getName() ) );
}
/**
* Copy file from source to destination. The directories up to <code>destination</code> will be
* created if they don't already exist. <code>destination</code> will be overwritten if it
* already exists.
*
* @param source An existing non-directory <code>File</code> to copy bytes from.
* @param destination A non-directory <code>File</code> to write bytes to (possibly
* overwriting).
* @throws IOException if <code>source</code> does not exist, <code>destination</code> cannot be
* written to, or an IO error occurs during copying.
* @throws java.io.FileNotFoundException if <code>destination</code> is a directory
*/
public static void copyFile( @Nonnull final File source, @Nonnull final File destination )
throws IOException
{
//check source exists
if ( !source.exists() )
{
final String message = "File " + source + " does not exist";
throw new IOException( message );
}
if ( Files.isSymbolicLink( source.toPath() ) )
{
File target = Files.readSymbolicLink( source.toPath() ).toFile();
Java7Support.createSymbolicLink( destination, target );
return;
}
//check source != destination, see PLXUTILS-10
if ( source.getCanonicalPath().equals( destination.getCanonicalPath() ) )
{
//if they are equal, we can exit the method without doing any work
return;
}
mkdirsFor( destination );
doCopyFile( source, destination );
if ( source.length() != destination.length() )
{
final String message = "Failed to copy full contents from " + source + " to " + destination;
throw new IOException( message );
}
}
private static void mkdirsFor( @Nonnull File destination )
{
//does destination directory exist ?
if ( destination.getParentFile() != null && !destination.getParentFile().exists() )
{
//noinspection ResultOfMethodCallIgnored
destination.getParentFile().mkdirs();
}
}
private static void doCopyFile( @Nonnull File source, @Nonnull File destination )
throws IOException
{
try ( FileInputStream fis = new FileInputStream( source );
FileOutputStream fos = new FileOutputStream( destination );
FileChannel input = fis.getChannel();
FileChannel output = fos.getChannel(); )
{
long size = input.size();
long pos = 0;
long count;
while ( pos < size )
{
count = size - pos > FILE_COPY_BUFFER_SIZE ? FILE_COPY_BUFFER_SIZE : size - pos;
pos += output.transferFrom( input, pos, count );
}
}
}
/**
* Copy file from source to destination only if source timestamp is later than the destination timestamp.
* The directories up to <code>destination</code> will be created if they don't already exist.
* <code>destination</code> will be overwritten if it already exists.
*
* @param source An existing non-directory <code>File</code> to copy bytes from.
* @param destination A non-directory <code>File</code> to write bytes to (possibly
* overwriting).
* @return true if no problem occured
* @throws IOException if <code>source</code> does not exist, <code>destination</code> cannot be
* written to, or an IO error occurs during copying.
*/
private static boolean copyFileIfModified( @Nonnull final File source, @Nonnull final File destination )
throws IOException
{
if ( destination.lastModified() < source.lastModified() )
{
copyFile( source, destination );
return true;
}
return false;
}
/**
* Copies bytes from the URL <code>source</code> to a file <code>destination</code>.
* The directories up to <code>destination</code> will be created if they don't already exist.
* <code>destination</code> will be overwritten if it already exists.
*
* @param source A <code>URL</code> to copy bytes from.
* @param destination A non-directory <code>File</code> to write bytes to (possibly
* overwriting).
* @throws IOException if
* <ul>
* <li><code>source</code> URL cannot be opened</li>
* <li><code>destination</code> cannot be written to</li>
* <li>an IO error occurs during copying</li>
* </ul>
*/
public static void copyURLToFile( @Nonnull final URL source, @Nonnull final File destination )
throws IOException
{
copyStreamToFile( source.openStream(), destination );
}
/**
* Copies bytes from the {@link InputStream} <code>source</code> to a file <code>destination</code>.
* The directories up to <code>destination</code> will be created if they don't already exist.
* <code>destination</code> will be overwritten if it already exists.
*
* @param source An {@link InputStream} to copy bytes from. This stream is
* guaranteed to be closed.
* @param destination A non-directory <code>File</code> to write bytes to (possibly
* overwriting).
* @throws IOException if
* <ul>
* <li><code>source</code> URL cannot be opened</li>
* <li><code>destination</code> cannot be written to</li>
* <li>an IO error occurs during copying</li>
* </ul>
*/
private static void copyStreamToFile( @Nonnull @WillClose final InputStream source,
@Nonnull final File destination )
throws IOException
{
//does destination directory exist ?
if ( destination.getParentFile() != null && !destination.getParentFile().exists() )
{
//noinspection ResultOfMethodCallIgnored
destination.getParentFile().mkdirs();
}
//make sure we can write to destination
if ( destination.exists() && !destination.canWrite() )
{
final String message = "Unable to open file " + destination + " for writing.";
throw new IOException( message );
}
try ( InputStream in = source;
OutputStream out = new FileOutputStream( destination ) )
{
IOUtil.copy( in, out );
}
}
/**
* Normalize a path.
* Eliminates "/../" and "/./" in a string. Returns <code>null</code> if the ..'s went past the
* root.
* Eg:
* <pre>
* /foo// --> /foo/
* /foo/./ --> /foo/
* /foo/../bar --> /bar
* /foo/../bar/ --> /bar/
* /foo/../bar/../baz --> /baz
* //foo//./bar --> /foo/bar
* /../ --> null
* </pre>
*
* @param path the path to normalize
* @return the normalized String, or <code>null</code> if too many ..'s.
*/
@Nonnull public static String normalize( @Nonnull final String path )
{
String normalized = path;
// Resolve occurrences of "//" in the normalized path
while ( true )
{
int index = normalized.indexOf( "//" );
if ( index < 0 )
{
break;
}
normalized = normalized.substring( 0, index ) + normalized.substring( index + 1 );
}
// Resolve occurrences of "/./" in the normalized path
while ( true )
{
int index = normalized.indexOf( "/./" );
if ( index < 0 )
{
break;
}
normalized = normalized.substring( 0, index ) + normalized.substring( index + 2 );
}
// Resolve occurrences of "/../" in the normalized path
while ( true )
{
int index = normalized.indexOf( "/../" );
if ( index < 0 )
{
break;
}
if ( index == 0 )
{
return null; // Trying to go outside our context
}
int index2 = normalized.lastIndexOf( '/', index - 1 );
normalized = normalized.substring( 0, index2 ) + normalized.substring( index + 3 );
}
// Return the normalized path that we have completed
return normalized;
}
/**
* Resolve a file <code>filename</code> to it's canonical form. If <code>filename</code> is
* relative (doesn't start with <code>/</code>), it will be resolved relative to
* <code>baseFile</code>, otherwise it is treated as a normal root-relative path.
*
* @param baseFile Where to resolve <code>filename</code> from, if <code>filename</code> is
* relative.
* @param filename Absolute or relative file path to resolve.
* @return The canonical <code>File</code> of <code>filename</code>.
*/
@Nonnull public static File resolveFile( final File baseFile, @Nonnull String filename )
{
String filenm = filename;
if ( '/' != File.separatorChar )
{
filenm = filename.replace( '/', File.separatorChar );
}
if ( '\\' != File.separatorChar )
{
filenm = filename.replace( '\\', File.separatorChar );
}
// deal with absolute files
if ( filenm.startsWith( File.separator ) || ( Os.isFamily( Os.FAMILY_WINDOWS ) && filenm.indexOf( ":" ) > 0 ) )
{
File file = new File( filenm );
try
{
file = file.getCanonicalFile();
}
catch ( final IOException ioe )
{
// nop
}
return file;
}
// FIXME: I'm almost certain this // removal is unnecessary, as getAbsoluteFile() strips
// them. However, I'm not sure about this UNC stuff. (JT)
final char[] chars = filename.toCharArray();
final StringBuilder sb = new StringBuilder();
//remove duplicate file separators in succession - except
//on win32 at start of filename as UNC filenames can
//be \\AComputer\AShare\myfile.txt
int start = 0;
if ( '\\' == File.separatorChar )
{
sb.append( filenm.charAt( 0 ) );
start++;
}
for ( int i = start; i < chars.length; i++ )
{
final boolean doubleSeparator = File.separatorChar == chars[i] && File.separatorChar == chars[i - 1];
if ( !doubleSeparator )
{
sb.append( chars[i] );
}
}
filenm = sb.toString();
//must be relative
File file = ( new File( baseFile, filenm ) ).getAbsoluteFile();
try
{
file = file.getCanonicalFile();
}
catch ( final IOException ioe )
{
// nop
}
return file;
}
/**
* Delete a file. If file is directory delete it and all sub-directories.
*
* @param file the file path
* @throws IOException if any
*/
public static void forceDelete( @Nonnull final String file )
throws IOException
{
forceDelete( new File( file ) );
}
/**
* Delete a file. If file is directory delete it and all sub-directories.
*
* @param file a file
* @throws IOException if any
*/
public static void forceDelete( @Nonnull final File file )
throws IOException
{
if ( file.isDirectory() )
{
deleteDirectory( file );
}
else
{
/*
* NOTE: Always try to delete the file even if it appears to be non-existent. This will ensure that a
* symlink whose target does not exist is deleted, too.
*/
boolean filePresent = file.getCanonicalFile().exists();
if ( !deleteFile( file ) && filePresent )
{
final String message = "File " + file + " unable to be deleted.";
throw new IOException( message );
}
}
}
/**
* deletes a file.
*
* @param file The file to delete
* @throws IOException If the file cannot be delted.
*/
public static void delete( @Nonnull File file )
throws IOException
{
if ( Java7Support.isAtLeastJava7() )
{
Java7Support.delete( file );
}
else
{
if ( !file.delete() )
{
throw new IOException( "Could not delete " + file.getName() );
}
}
}
/**
* @param file The file.
* @return true / false
*/
public static boolean deleteLegacyStyle( @Nonnull File file )
{
if ( Java7Support.isAtLeastJava7() )
{
try
{
Java7Support.delete( file );
return true;
}
catch ( IOException e )
{
return false;
}
}
else
{
return file.delete();
}
}
/**
* Accommodate Windows bug encountered in both Sun and IBM JDKs.
* Others possible. If the delete does not work, call System.gc(),
* wait a little and try again.
*
* @param file a file
* @throws IOException if any
*/
private static boolean deleteFile( @Nonnull File file )
throws IOException
{
if ( file.isDirectory() )
{
throw new IOException( "File " + file + " isn't a file." );
}
if ( !deleteLegacyStyle( file ) )
{
if ( Os.isFamily( Os.FAMILY_WINDOWS ) )
{
file = file.getCanonicalFile();
}
try
{
Thread.sleep( 10 );
return deleteLegacyStyle( file );
}
catch ( InterruptedException ex )
{
return deleteLegacyStyle( file );
}
}
return true;
}
/**
* Make a directory.
*
* @param file not null
* @throws IOException If there already exists a file with specified name or
* the directory is unable to be created
* @throws IllegalArgumentException if the file contains illegal Windows characters under Windows OS.
* @see #INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME
*/
public static void forceMkdir( @Nonnull final File file )
throws IOException
{
if ( Os.isFamily( Os.FAMILY_WINDOWS ) && !isValidWindowsFileName( file ) )
{
throw new IllegalArgumentException(
"The file (" + file.getAbsolutePath() + ") cannot contain any of the following characters: \n"
+ StringUtils.join( INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME, " " ) );
}
if ( file.exists() )
{
if ( file.isFile() )
{
final String message =
"File " + file + " exists and is " + "not a directory. Unable to create directory.";
throw new IOException( message );
}
}
else
{
if ( !file.mkdirs() )
{
final String message = "Unable to create directory " + file;
throw new IOException( message );
}
}
}
/**
* Recursively delete a directory.
*
* @param directory a directory
* @throws IOException if any
*/
public static void deleteDirectory( @Nonnull final String directory )
throws IOException
{
deleteDirectory( new File( directory ) );
}
/**
* Recursively delete a directory.
*
* @param directory a directory
* @throws IOException if any
*/
public static void deleteDirectory( @Nonnull final File directory )
throws IOException
{
if ( !directory.exists() )
{
return;
}
/* try delete the directory before its contents, which will take
* care of any directories that are really symbolic links.
*/
if ( deleteLegacyStyle( directory ) )
{
return;
}
cleanDirectory( directory );
if ( !deleteLegacyStyle( directory ) )
{
final String message = "Directory " + directory + " unable to be deleted.";
throw new IOException( message );
}
}
/**
* Clean a directory without deleting it.
*
* @param directory a directory
* @throws IOException if any
*/
public static void cleanDirectory( @Nonnull final File directory )
throws IOException
{
if ( !directory.exists() )
{
final String message = directory + " does not exist";
throw new IllegalArgumentException( message );
}
if ( !directory.isDirectory() )
{
final String message = directory + " is not a directory";
throw new IllegalArgumentException( message );
}
IOException exception = null;
final File[] files = directory.listFiles();
if ( files == null )
{
return;
}
for ( final File file : files )
{
try
{
forceDelete( file );
}
catch ( final IOException ioe )
{
exception = ioe;
}
}
if ( null != exception )
{
throw exception;
}
}
/**
* Recursively count size of a directory.
*
* @param directory a directory
* @return size of directory in bytes.
*/
public static long sizeOfDirectory( @Nonnull final String directory )
{
return sizeOfDirectory( new File( directory ) );
}
/**
* Recursively count size of a directory.
*
* @param directory a directory
* @return size of directory in bytes.
*/
public static long sizeOfDirectory( @Nonnull final File directory )
{
if ( !directory.exists() )
{
final String message = directory + " does not exist";
throw new IllegalArgumentException( message );
}
if ( !directory.isDirectory() )
{
final String message = directory + " is not a directory";
throw new IllegalArgumentException( message );
}
long size = 0;
final File[] files = directory.listFiles();
if ( files == null )
{
throw new IllegalArgumentException( "Problems reading directory" );
}
for ( final File file : files )
{
if ( file.isDirectory() )
{
size += sizeOfDirectory( file );
}
else
{
size += file.length();
}
}
return size;
}
/**
* Return the files contained in the directory, using inclusion and exclusion Ant patterns,
* including the directory name in each of the files
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @return a list of File objects
* @throws IOException in case of failure.
* @see #getFileNames(File, String, String, boolean)
*/
@Nonnull
public static List<File> getFiles( @Nonnull File directory, @Nullable String includes, @Nullable String excludes )
throws IOException
{
return getFiles( directory, includes, excludes, true );
}
/**
* Return the files contained in the directory, using inclusion and exclusion Ant patterns
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @param includeBasedir true to include the base dir in each file
* @return a list of File objects
* @throws IOException in case of failure.
* @see #getFileNames(File, String, String, boolean)
*/
@Nonnull
public static List<File> getFiles( @Nonnull File directory, @Nullable String includes, @Nullable String excludes,
boolean includeBasedir )
throws IOException
{
List<String> fileNames = getFileNames( directory, includes, excludes, includeBasedir );
List<File> files = new ArrayList<>();
for ( String filename : fileNames )
{
files.add( new File( filename ) );
}
return files;
}
/**
* Return a list of files as String depending options.
* This method use case sensitive file name.
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @param includeBasedir true to include the base dir in each String of file
* @return a list of files as String
* @throws IOException in case of failure.
*/
@Nonnull public static List<String> getFileNames( @Nonnull File directory, @Nullable String includes,
@Nullable String excludes, boolean includeBasedir )
throws IOException
{
return getFileNames( directory, includes, excludes, includeBasedir, true );
}
/**
* Return a list of files as String depending options.
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @param includeBasedir true to include the base dir in each String of file
* @param isCaseSensitive true if case sensitive
* @return a list of files as String
* @throws IOException
*/
@Nonnull private static List<String> getFileNames( @Nonnull File directory, @Nullable String includes,
@Nullable String excludes, boolean includeBasedir,
boolean isCaseSensitive )
throws IOException
{
return getFileAndDirectoryNames( directory, includes, excludes, includeBasedir, isCaseSensitive, true, false );
}
/**
* Return a list of directories as String depending options.
* This method use case sensitive file name.
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @param includeBasedir true to include the base dir in each String of file
* @return a list of directories as String
* @throws IOException in case of failure.
*/
@Nonnull public static List<String> getDirectoryNames( @Nonnull File directory, @Nullable String includes,
@Nullable String excludes, boolean includeBasedir )
throws IOException
{
return getDirectoryNames( directory, includes, excludes, includeBasedir, true );
}
/**
* Return a list of directories as String depending options.
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @param includeBasedir true to include the base dir in each String of file
* @param isCaseSensitive true if case sensitive
* @return a list of directories as String
* @throws IOException in case of failure.
*/
@Nonnull public static List<String> getDirectoryNames( @Nonnull File directory, @Nullable String includes,
@Nullable String excludes, boolean includeBasedir,
boolean isCaseSensitive )
throws IOException
{
return getFileAndDirectoryNames( directory, includes, excludes, includeBasedir, isCaseSensitive, false, true );
}
/**
* Return a list of files as String depending options.
*
* @param directory the directory to scan
* @param includes the includes pattern, comma separated
* @param excludes the excludes pattern, comma separated
* @param includeBasedir true to include the base dir in each String of file
* @param isCaseSensitive true if case sensitive
* @param getFiles true if get files
* @param getDirectories true if get directories
* @return a list of files as String
*/
@Nonnull public static List<String> getFileAndDirectoryNames( File directory, @Nullable String includes,
@Nullable String excludes, boolean includeBasedir,
boolean isCaseSensitive, boolean getFiles,
boolean getDirectories )
{
DirectoryScanner scanner = new DirectoryScanner();
scanner.setBasedir( directory );
if ( includes != null )
{
scanner.setIncludes( StringUtils.split( includes, "," ) );
}
if ( excludes != null )
{
scanner.setExcludes( StringUtils.split( excludes, "," ) );
}
scanner.setCaseSensitive( isCaseSensitive );
scanner.scan();
List<String> list = new ArrayList<>();
if ( getFiles )
{
String[] files = scanner.getIncludedFiles();
for ( String file : files )
{
if ( includeBasedir )
{
list.add( directory + File.separator + file );
}
else
{
list.add( file );
}
}
}
if ( getDirectories )
{
String[] directories = scanner.getIncludedDirectories();
for ( String directory1 : directories )
{
if ( includeBasedir )
{
list.add( directory + File.separator + directory1 );
}
else
{
list.add( directory1 );
}
}
}
return list;
}
/**
* Copy a directory to an other one.
*
* @param sourceDirectory the source dir
* @param destinationDirectory the target dir
* @throws IOException if any
*/
public static void copyDirectory( @Nonnull File sourceDirectory, @Nonnull File destinationDirectory )
throws IOException
{
copyDirectory( sourceDirectory, destinationDirectory, "**", null );
}
/**
* Copy a directory to an other one.
*
* @param sourceDirectory the source dir
* @param destinationDirectory the target dir
* @param includes include pattern
* @param excludes exlucde pattern
* @throws IOException if any
* @see #getFiles(File, String, String)
*/
public static void copyDirectory( @Nonnull File sourceDirectory, @Nonnull File destinationDirectory,
@Nullable String includes, @Nullable String excludes )
throws IOException
{
if ( !sourceDirectory.exists() )
{
return;
}
List<File> files = getFiles( sourceDirectory, includes, excludes );
for ( File file : files )
{
copyFileToDirectory( file, destinationDirectory );
}
}
/**
* Copies a entire directory structure.
* <p/>
* Note:
* <ul>
* <li>It will include empty directories.
* <li>The <code>sourceDirectory</code> must exists.
* </ul>
*
* @param sourceDirectory the source dir
* @param destinationDirectory the target dir
* @throws IOException if any
*/
public static void copyDirectoryStructure( @Nonnull File sourceDirectory, @Nonnull File destinationDirectory )
throws IOException
{
copyDirectoryStructure( sourceDirectory, destinationDirectory, destinationDirectory, false );
}
private static void copyDirectoryStructure( @Nonnull File sourceDirectory, @Nonnull File destinationDirectory,
File rootDestinationDirectory, boolean onlyModifiedFiles )
throws IOException
{
//noinspection ConstantConditions
if ( sourceDirectory == null )
{
throw new IOException( "source directory can't be null." );
}
//noinspection ConstantConditions
if ( destinationDirectory == null )
{
throw new IOException( "destination directory can't be null." );
}
if ( sourceDirectory.equals( destinationDirectory ) )
{
throw new IOException( "source and destination are the same directory." );
}
if ( !sourceDirectory.exists() )
{
throw new IOException( "Source directory doesn't exists (" + sourceDirectory.getAbsolutePath() + ")." );
}
File[] files = sourceDirectory.listFiles();
if ( files == null )
{
return;
}
String sourcePath = sourceDirectory.getAbsolutePath();
for ( File file : files )
{
if ( file.equals( rootDestinationDirectory ) )
{
// We don't copy the destination directory in itself
continue;
}
String dest = file.getAbsolutePath();
dest = dest.substring( sourcePath.length() + 1 );
File destination = new File( destinationDirectory, dest );
if ( file.isFile() )
{
destination = destination.getParentFile();
if ( onlyModifiedFiles )
{
copyFileToDirectoryIfModified( file, destination );
}
else
{
copyFileToDirectory( file, destination );
}
}
else if ( file.isDirectory() )
{
if ( !destination.exists() && !destination.mkdirs() )
{
throw new IOException(
"Could not create destination directory '" + destination.getAbsolutePath() + "'." );
}
copyDirectoryStructure( file, destination, rootDestinationDirectory, onlyModifiedFiles );
}
else
{
throw new IOException( "Unknown file type: " + file.getAbsolutePath() );
}
}
}
/**
* Renames a file, even if that involves crossing file system boundaries.
* <p/>
* <p>This will remove <code>to</code> (if it exists), ensure that
* <code>to</code>'s parent directory exists and move
* <code>from</code>, which involves deleting <code>from</code> as
* well.</p>
*
* @param from the file to move
* @param to the new file name
* @throws IOException if anything bad happens during this process.
* Note that <code>to</code> may have been deleted already when this happens.
*/
public static void rename( @Nonnull File from, @Nonnull File to )
throws IOException
{
if ( to.exists() && !deleteLegacyStyle( to ) )
{
throw new IOException( "Failed to delete " + to + " while trying to rename " + from );
}
File parent = to.getParentFile();
if ( parent != null && !parent.exists() && !parent.mkdirs() )
{
throw new IOException( "Failed to create directory " + parent + " while trying to rename " + from );
}
if ( !from.renameTo( to ) )
{
copyFile( from, to );
if ( !deleteLegacyStyle( from ) )
{
throw new IOException( "Failed to delete " + from + " while trying to rename it." );
}
}
}
/**
* Create a temporary file in a given directory.
* <p/>
* <p>The file denoted by the returned abstract pathname did not
* exist before this method was invoked, any subsequent invocation
* of this method will yield a different file name.</p>
* <p/>
* The filename is prefixNNNNNsuffix where NNNN is a random number
* </p>
* <p>This method is different to {@link File#createTempFile(String, String, File)} of JDK 1.2
* as it doesn't create the file itself.
* It uses the location pointed to by java.io.tmpdir
* when the parentDir attribute is
* null.</p>
* <p>To delete automatically the file created by this method, use the
* {@link File#deleteOnExit()} method.</p>
*
* @param prefix prefix before the random number
* @param suffix file extension; include the '.'
* @param parentDir Directory to create the temporary file in <code>-java.io.tmpdir</code>
* used if not specificed
* @return a File reference to the new temporary file.
*/
public static File createTempFile( @Nonnull String prefix, @Nonnull String suffix, @Nullable File parentDir )
{
File result;
String parent = System.getProperty( "java.io.tmpdir" );
if ( parentDir != null )
{
parent = parentDir.getPath();
}
DecimalFormat fmt = new DecimalFormat( "#####" );
SecureRandom secureRandom = new SecureRandom();
long secureInitializer = secureRandom.nextLong();
Random rand = new Random( secureInitializer + Runtime.getRuntime().freeMemory() );
do
{
result = new File( parent, prefix + fmt.format( positiveRandom( rand ) ) + suffix );
}
while ( result.exists() );
return result;
}
private static int positiveRandom( Random rand )
{
int a = rand.nextInt();
while ( a == Integer.MIN_VALUE )
{
a = rand.nextInt();
}
return Math.abs( a );
}
/**
* <b>If wrappers is null or empty, the file will be copy only if to.lastModified() < from.lastModified()</b>
*
* @param from the file to copy
* @param to the destination file
* @param encoding the file output encoding (only if wrappers is not empty)
* @param wrappers array of {@link FilterWrapper}
* @throws IOException if an IO error occurs during copying or filtering
*/
public static void copyFile( @Nonnull File from, @Nonnull File to, @Nullable String encoding,
@Nullable FilterWrapper... wrappers )
throws IOException
{
copyFile( from, to, encoding, wrappers, false );
}
/**
* Wrapper class for Filter.
*
*/
public abstract static class FilterWrapper
{
/**
* @param fileReader {@link Reader}
* @return The Reader instance.
*/
public abstract Reader getReader( Reader fileReader );
}
/**
* <b>If wrappers is null or empty, the file will be copy only if to.lastModified() < from.lastModified() or if
* overwrite is true</b>
*
* @param from the file to copy
* @param to the destination file
* @param encoding the file output encoding (only if wrappers is not empty)
* @param wrappers array of {@link FilterWrapper}
* @param overwrite if true and f wrappers is null or empty, the file will be copy enven if to.lastModified() <
* from.lastModified()
* @throws IOException if an IO error occurs during copying or filtering
*/
public static void copyFile( @Nonnull File from, @Nonnull File to, @Nullable String encoding,
@Nullable FilterWrapper[] wrappers, boolean overwrite )
throws IOException
{
if ( wrappers != null && wrappers.length > 0 )
{
// buffer so it isn't reading a byte at a time!
Reader fileReader = null;
Writer fileWriter = null;
try
{
if ( encoding == null || encoding.length() < 1 )
{
fileReader = new BufferedReader( new FileReader( from ) );
fileWriter = new FileWriter( to );
}
else
{
fileReader = new BufferedReader( new InputStreamReader( new FileInputStream( from ), encoding ) );
fileWriter = new OutputStreamWriter( new FileOutputStream( to ), encoding );
}
for ( FilterWrapper wrapper : wrappers )
{
fileReader = wrapper.getReader( fileReader );
}
IOUtil.copy( fileReader, fileWriter );
fileWriter.close();
fileWriter = null;
fileReader.close();
fileReader = null;
}
finally
{
IOUtil.close( fileReader );
IOUtil.close( fileWriter );
}
}
else
{
if ( to.lastModified() < from.lastModified() || overwrite )
{
copyFile( from, to );
}
}
}
/**
* Note: the file content is read with platform encoding
*
* @param file the file
* @return a List containing every every line not starting with # and not empty
* @throws IOException if any
*/
@Nonnull public static List<String> loadFile( @Nonnull File file )
throws IOException
{
List<String> lines = new ArrayList<>();
if ( file.exists() )
{
try ( BufferedReader reader = new BufferedReader( new FileReader( file ) ) )
{
for ( String line = reader.readLine(); line != null; line = reader.readLine() )
{
line = line.trim();
if ( !line.startsWith( "#" ) && line.length() != 0 )
{
lines.add( line );
}
}
}
}
return lines;
}
/**
* For Windows OS, check if the file name contains any of the following characters:
* <code>":", "*", "?", "\"", "<", ">", "|"</code>
*
* @param f not null file
* @return <code>false</code> if the file path contains any of forbidden Windows characters,
* <code>true</code> if the Os is not Windows or if the file path respect the Windows constraints.
* @see #INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME
*/
private static boolean isValidWindowsFileName( @Nonnull File f )
{
if ( Os.isFamily( Os.FAMILY_WINDOWS ) )
{
if ( StringUtils.indexOfAny( f.getName(), INVALID_CHARACTERS_FOR_WINDOWS_FILE_NAME ) != -1 )
{
return false;
}
if ( f.getParentFile() != null )
{
return isValidWindowsFileName( f.getParentFile() );
}
}
return true;
}
/**
* Checks whether a given file is a symbolic link.
*
* @param file the file to check
* @throws IOException in case of failure.
* @return true if symbolic link false otherwise.
* @deprecated Use {@link Files#isSymbolicLink(java.nio.file.Path)} instead
*/
@Deprecated
public static boolean isSymbolicLink( @Nonnull final File file )
throws IOException
{
return Files.isSymbolicLink( file.toPath() );
}
/**
* Checks whether a given file is a symbolic link.
*
* @param file the file to check
* @return true if and only if we reliably can say this is a symlink.
*
* @throws IOException in case of failure.
* @deprecated Use {@link Files#isSymbolicLink(java.nio.file.Path)} instead
*/
@Deprecated
public static boolean isSymbolicLinkForSure( @Nonnull final File file )
throws IOException
{
// Used to return false for Java 6 and older
return Files.isSymbolicLink( file.toPath() );
}
/**
* Checks whether a given file is a symbolic link.
* <p>
* It doesn't really test for symbolic links but whether the canonical and absolute
* paths of the file are identical - this may lead to false positives on some platforms.
*
* It also returns true for any file that has been reached via a symbolic link,
* if you decide to traverse into the symlink.
*
* As can be seen from the "return" clause of this method, there is really no
* guarantee of any sort from this method. Small wonder this ever got used for
* anything.
* </p>
*
* @param file the file to check
* @return true if the file is a symbolic link or if we're on some crappy os.
* false if the file is not a symlink or we're not able to detect it.
*/
static boolean isSymbolicLinkLegacy( @Nonnull final File file )
throws IOException
{
final File canonical = new File( file.getCanonicalPath() );
return !file.getAbsolutePath().equals( canonical.getPath() );
}
}