org.opencastproject.util

Class FileSupport

java.lang.Object

org.opencastproject.util.FileSupport

public final class FileSupport
extends Object

Utility class, dealing with files.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DELETE_CONTENT Delete all content but keep the root directory.
static int	DELETE_FILES Only files will be deleted, the directory structure remains untouched.
static int	DELETE_ROOT Delete everything including the root directory.

Method Summary

Modifier and Type	Method and Description
static File	copy(File sourceLocation, File targetLocation) Copies the specified file from sourceLocation to targetLocation and returns a reference to the newly created file or directory.
static File	copy(File sourceFile, File targetFile, boolean overwrite) Copies the specified sourceLocation to targetLocation and returns a reference to the newly created file or directory.
static void	copyContent(File sourceDirectory, File targetDirectory) Copies recursively the content of the specified sourceDirectory to targetDirectory.
static void	copyContent(File sourceDirectory, File targetDirectory, boolean overwrite) Copies recursively the content of the specified sourceDirectory to targetDirectory.
static boolean	delete(File f) Deletes the specified file and returns true if the file was deleted.
static boolean	delete(File f, boolean recurse) Deletes the specified file and returns true if the file was deleted.
static boolean	delete(File dir, int mode) Deletes the content of directory dir and, if specified, the directory itself.
static boolean	deleteHierarchyIfEmpty(File limit, File start) Delete all directories from start up to directory limit if they are empty.
static boolean	deleteQuietly(File f) Like delete(File) but does not throw any IO exceptions.
static boolean	deleteQuietly(File f, boolean recurse) Like delete(File, boolean) but does not throw any IO exceptions.
static boolean	equals(File a, File b) Returns true if both canonical file paths are equal.
static File	getTempDirectory() Returns the webapp's temporary work directory.
static File	getTempDirectory(String subdir) Returns a directory subdir inside the webapp's temporary work directory.
static boolean	isEqual(File a, File b) Compare two files by their canonical paths.
static boolean	isParent(File a, File b) Check if a is a parent of b.
static File	link(File sourceLocation, File targetLocation) Links the specified file or directory from sourceLocation to targetLocation.
static File	link(File sourceLocation, File targetLocation, boolean overwrite) Links the specified file or directory from sourceLocation to targetLocation.
static File	move(File sourceLocation, File targetDirectory) Moves the specified file or directory from sourceLocation to targetDirectory.
static void	setTempDirectory(File tmpDir) Sets the webapp's temporary directory.
static boolean	supportsLinking(File sourceLocation, File targetLocation) Returns true if the operating system as well as the disk layout support creating a hard link from src to dest.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DELETE_FILES

public static final int DELETE_FILES

Only files will be deleted, the directory structure remains untouched.

See Also:

Constant Field Values

DELETE_ROOT

public static final int DELETE_ROOT

Delete everything including the root directory.

See Also:

Constant Field Values

DELETE_CONTENT

public static final int DELETE_CONTENT

Delete all content but keep the root directory.

See Also:

Constant Field Values

Method Detail

move

public static File move(File sourceLocation,
                        File targetDirectory)
                 throws IOException

Moves the specified file or directory from sourceLocation to targetDirectory. If targetDirectory does not exist, it will be created.

Parameters:

sourceLocation - the source file or directory

targetDirectory - the target directory

Returns:

the moved file

Throws:

IOException

copy

public static File copy(File sourceLocation,
                        File targetLocation)
                 throws IOException

Copies the specified file from sourceLocation to targetLocation and returns a reference to the newly created file or directory.

If targetLocation is an existing directory, then the source file or directory will be copied into this directory, otherwise the source file will be copied to the file identified by targetLocation.

Note that existing files and directories will be overwritten.

Also note that if targetLocation is a directory than the directory itself, not only its content is copied.

Parameters:

sourceLocation - the source file or directory

targetLocation - the directory to copy the source file or directory to

Returns:

the created copy

Throws:

IOException - if copying of the file or directory failed

copy

public static File copy(File sourceFile,
                        File targetFile,
                        boolean overwrite)
                 throws IOException

Copies the specified sourceLocation to targetLocation and returns a reference to the newly created file or directory.

If targetLocation is an existing directory, then the source file or directory will be copied into this directory, otherwise the source file will be copied to the file identified by targetLocation.

If overwrite is set to false, this method throws an IOException if the target file already exists.

Note that if targetLocation is a directory than the directory itself, not only its content is copied.

Parameters:

sourceFile - the source file or directory

targetFile - the directory to copy the source file or directory to

overwrite - true to overwrite existing files

Returns:

the created copy

Throws:

IOException - if copying of the file or directory failed

copyContent

public static void copyContent(File sourceDirectory,
                               File targetDirectory,
                               boolean overwrite)
                        throws IOException

Copies recursively the content of the specified sourceDirectory to targetDirectory.

If overwrite is set to false, this method throws an IOException if the target file already exists.

Parameters:

sourceDirectory - the source directory

targetDirectory - the target directory to copy the content of the source directory to

overwrite - true to overwrite existing files

Throws:

IOException - if copying fails

copyContent

public static void copyContent(File sourceDirectory,
                               File targetDirectory)
                        throws IOException

Copies recursively the content of the specified sourceDirectory to targetDirectory.

Note that existing files and directories will be overwritten.

Parameters:

sourceDirectory - the source directory

targetDirectory - the target directory to copy the content of the source directory to

Throws:

IOException - if copying fails

link

public static File link(File sourceLocation,
                        File targetLocation)
                 throws IOException

Links the specified file or directory from sourceLocation to targetLocation. If targetLocation does not exist, it will be created, if the target file already exists, an IOException will be thrown.

If this fails (because linking is not supported on the current filesystem, then a copy is made.

Parameters:

sourceLocation - the source file or directory

targetLocation - the targetLocation

Returns:

the created link

Throws:

IOException - if linking of the file or directory failed

link

public static File link(File sourceLocation,
                        File targetLocation,
                        boolean overwrite)
                 throws IOException

Links the specified file or directory from sourceLocation to targetLocation. If targetLocation does not exist, it will be created.

If this fails (because linking is not supported on the current filesystem, then a copy is made.

If overwrite is set to false, this method throws an IOException if the target file already exists.

Parameters:

sourceLocation - the source file or directory

targetLocation - the targetLocation

overwrite - true to overwrite existing files

Returns:

the created link

Throws:

IOException - if linking of the file or directory failed

supportsLinking

public static boolean supportsLinking(File sourceLocation,
                                      File targetLocation)

Returns true if the operating system as well as the disk layout support creating a hard link from src to dest. Note that this implementation requires two files rather than directories and will overwrite any existing file that might already be present at the destination.

Parameters:

sourceLocation - the source file

targetLocation - the target file

Returns:

true if the link was created, false otherwhise

deleteHierarchyIfEmpty

public static boolean deleteHierarchyIfEmpty(File limit,
                                             File start)

Delete all directories from start up to directory limit if they are empty. Directory limit is exclusive and will not be deleted.

Returns:

true if the complete hierarchy has been deleted. false in any other case.

isEqual

public static boolean isEqual(File a,
                              File b)

Compare two files by their canonical paths.

isParent

public static boolean isParent(File a,
                               File b)

Check if a is a parent of b. This can only be the case if a is a directory and a sub path of b. isParent(a, a) == true.

delete

public static boolean delete(File f)
                      throws IOException

Deletes the specified file and returns true if the file was deleted.

If f is a directory, it will only be deleted if it doesn't contain any other files or directories. To do a recursive delete, you may use delete(File, boolean).

Parameters:

f - the file or directory

Throws:

IOException

See Also:

delete(File, boolean)

deleteQuietly

public static boolean deleteQuietly(File f)

Like delete(File) but does not throw any IO exceptions. In case of an IOException it will only be logged at warning level and the method returns false.

deleteQuietly

public static boolean deleteQuietly(File f,
                                    boolean recurse)

Like delete(File, boolean) but does not throw any IO exceptions. In case of an IOException it will only be logged at warning level and the method returns false.

delete

public static boolean delete(File f,
                             boolean recurse)
                      throws IOException

Deletes the specified file and returns true if the file was deleted.

In the case that f references a directory, it will only be deleted if it doesn't contain other files or directories, unless recurse is set to true.

Parameters:

f - the file or directory

recurse - true to do a recursive deletes for directories

Throws:

IOException

delete

public static boolean delete(File dir,
                             int mode)

Deletes the content of directory dir and, if specified, the directory itself. If dir is a normal file it will always be deleted.

Returns:

true everthing was deleted, false otherwise

setTempDirectory

public static void setTempDirectory(File tmpDir)
                             throws IllegalArgumentException,
                                    IllegalStateException

Sets the webapp's temporary directory. Make sure that directory exists and has write permissions turned on.

Parameters:

tmpDir - the new temporary directory

Throws:

IllegalArgumentException - if the file object doesn't represent a directory

IllegalStateException - if the directory is write protected

getTempDirectory

public static File getTempDirectory()

Returns the webapp's temporary work directory.

Returns:

the temp directory

getTempDirectory

public static File getTempDirectory(String subdir)

Returns a directory subdir inside the webapp's temporary work directory.

Parameters:

subdir - name of the subdirectory

Returns:

the ready to use temp directory

equals

public static boolean equals(File a,
                             File b)

Returns true if both canonical file paths are equal.

Parameters:

a - the first file or null

b - the second file or null