FileUtils (SciJava Javadocs 0-SNAPSHOT API)

java.lang.Object
- org.scijava.util.FileUtils

```
public final class FileUtils
extends Object
```
Useful methods for working with file paths.

Author:

Johannes Schindelin, Curtis Rueden, Grant Harris

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_SHORTENER_THRESHOLD`
`static String`	`SHORTENER_BACKSLASH`
`static String`	`SHORTENER_BACKSLASH_REGEX`
`static String`	`SHORTENER_ELLIPSE`
`static String`	`SHORTENER_SLASH`
`static String`	`SHORTENER_SLASH_REGEX`

Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`static Collection<URL>`	`appendContents(Collection<URL> result, URL directory)` Recursively adds contents from the referenced directory to an existing collection.
`static Collection<URL>`	`appendContents(Collection<URL> result, URL directory, boolean recurse, boolean filesOnly)` Add contents from the referenced directory to an existing collection.
`static File`	`createTemporaryDirectory(String prefix)` Creates a temporary directory.
`static File`	`createTemporaryDirectory(String prefix, String suffix)` Creates a temporary directory.
`static File`	`createTemporaryDirectory(String prefix, String suffix, File directory)` Creates a temporary directory.
`static boolean`	`deleteRecursively(File directory)` Deletes a directory recursively.
`static Map<String,URL>`	`findResources(String regex, Iterable<URL> urls)` Finds `URL`s of resources known to the system.
`static Map<String,URL>`	`findResources(String regex, String pathPrefix, File baseDirectory)` Finds `URL`s of available resources.
`static File[]`	`getAllVersions(File directory, String filename)` Lists all versions of a given (possibly versioned) file name.
`static String`	`getExtension(File file)` Extracts the file extension from a file.
`static String`	`getExtension(String path)` Extracts the file extension from a file path.
`static Date`	`getModifiedTime(File file)` Gets the `Date` of the file's last modification.
`static String`	`getPath(File file)` Gets the absolute path to the given file, with the directory separator standardized to forward slash, like most platforms use.
`static String`	`getPath(String path, String separator)` Gets a standardized path based on the given one, with the directory separator standardized from the specific separator to forward slash, like most platforms use.
`static String`	`limitPath(String path, int limit)` Compacts a path into a given number of characters.
`static Collection<URL>`	`listContents(URL directory)` Recursively lists the contents of the referenced directory.
`static Collection<URL>`	`listContents(URL directory, boolean recurse, boolean filesOnly)` Lists all contents of the referenced directory.
`static Matcher`	`matchVersionedFilename(String filename)` Deprecated. see `stripFilenameVersion(String)`
`static byte[]`	`readFile(File file)` Reads the contents of the given file into a new byte array.
`static String`	`shortenPath(String path)` Shortens the path to a maximum of 4 path elements.
`static String`	`shortenPath(String path, int threshold)` Shortens the path based on the given maximum number of path elements.
`static String`	`stripFilenameVersion(String filename)`
`static File`	`urlToFile(String url)` Converts the given URL string to its corresponding `File`.
`static File`	`urlToFile(URL url)` Converts the given `URL` to its corresponding `File`.
`static void`	`writeFile(File file, byte[] bytes)` Writes the given byte array to the specified file.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_SHORTENER_THRESHOLD
```
public static final int DEFAULT_SHORTENER_THRESHOLD
```
    See Also:
    
    Constant Field Values
  - SHORTENER_BACKSLASH_REGEX
```
public static final String SHORTENER_BACKSLASH_REGEX
```
    See Also:
    
    Constant Field Values
  - SHORTENER_SLASH_REGEX
```
public static final String SHORTENER_SLASH_REGEX
```
    See Also:
    
    Constant Field Values
  - SHORTENER_BACKSLASH
```
public static final String SHORTENER_BACKSLASH
```
    See Also:
    
    Constant Field Values
  - SHORTENER_SLASH
```
public static final String SHORTENER_SLASH
```
    See Also:
    
    Constant Field Values
  - SHORTENER_ELLIPSE
```
public static final String SHORTENER_ELLIPSE
```
    See Also:
    
    Constant Field Values
- Method Detail
  - getPath
```
public static String getPath(File file)
```
    Gets the absolute path to the given file, with the directory separator standardized to forward slash, like most platforms use.
    
    Parameters:
    
    file - The file whose path will be obtained and standardized.
    
    Returns:
    
    The file's standardized absolute path.
  - getPath
```
public static String getPath(String path,
                             String separator)
```
    Gets a standardized path based on the given one, with the directory separator standardized from the specific separator to forward slash, like most platforms use.
    
    Parameters:
    
    path - The path to standardize.
    
    separator - The directory separator to be standardized.
    
    Returns:
    
    The standardized path.
  - getExtension
```
public static String getExtension(File file)
```
    Extracts the file extension from a file.
    
    Parameters:
    
    file - the file object
    
    Returns:
    
    the file extension (excluding the dot), or the empty string when the file name does not contain dots
  - getExtension
```
public static String getExtension(String path)
```
    Extracts the file extension from a file path.
    
    Parameters:
    
    path - the path to the file (relative or absolute)
    
    Returns:
    
    the file extension (excluding the dot), or the empty string when the file name does not contain dots
  - getModifiedTime
```
public static Date getModifiedTime(File file)
```
    Gets the Date of the file's last modification.
  - readFile
```
public static byte[] readFile(File file)
                       throws IOException
```
    Reads the contents of the given file into a new byte array.
    
    Throws:
    
    IOException - If the file cannot be read.
    
    See Also:
    
    To convert a byte array to a string.
  - writeFile
```
public static void writeFile(File file,
                             byte[] bytes)
                      throws IOException
```
    Writes the given byte array to the specified file.
    
    Throws:
    
    IOException - If the file cannot be written.
    
    See Also:
    
    To convert a string to a byte array.
  - stripFilenameVersion
```
public static String stripFilenameVersion(String filename)
```
  - getAllVersions
```
public static File[] getAllVersions(File directory,
                                    String filename)
```
    Lists all versions of a given (possibly versioned) file name.
    
    Parameters:
    
    directory - the directory to scan
    
    filename - the file name to use
    
    Returns:
    
    the list of matches
  - urlToFile
```
public static File urlToFile(URL url)
```
    Converts the given URL to its corresponding File.
    This method is similar to calling new File(url.toURI()) except that it also handles "jar:file:" URLs, returning the path to the JAR file.
    
    Parameters:
    
    url - The URL to convert.
    
    Returns:
    
    A file path suitable for use with e.g. FileInputStream
    
    Throws:
    
    IllegalArgumentException - if the URL does not correspond to a file.
  - urlToFile
```
public static File urlToFile(String url)
```
    Converts the given URL string to its corresponding File.
    
    Parameters:
    
    url - The URL to convert.
    
    Returns:
    
    A file path suitable for use with e.g. FileInputStream
    
    Throws:
    
    IllegalArgumentException - if the URL does not correspond to a file.
  - shortenPath
```
public static String shortenPath(String path)
```
    Shortens the path to a maximum of 4 path elements.
    
    Parameters:
    
    path - the path to the file (relative or absolute)
    
    Returns:
    
    shortened path
  - shortenPath
```
public static String shortenPath(String path,
                                 int threshold)
```
    Shortens the path based on the given maximum number of path elements. E.g., "C:/1/2/test.txt" returns "C:/1/.../test.txt" if threshold is 1.
    
    Parameters:
    
    path - the path to the file (relative or absolute)
    
    threshold - the number of directories to keep unshortened
    
    Returns:
    
    shortened path
  - limitPath
```
public static String limitPath(String path,
                               int limit)
```
    Compacts a path into a given number of characters. The result is similar to the Win32 API PathCompactPathExA.
    
    Parameters:
    
    path - the path to the file (relative or absolute)
    
    limit - the number of characters to which the path should be limited
    
    Returns:
    
    shortened path
  - createTemporaryDirectory
```
public static File createTemporaryDirectory(String prefix)
                                     throws IOException
```
    Creates a temporary directory.
    Since there is no atomic operation to do that, we create a temporary file, delete it and create a directory in its place. To avoid race conditions, we use the optimistic approach: if the directory cannot be created, we try to obtain a new temporary file rather than erroring out.
    
    It is the caller's responsibility to make sure that the directory is deleted; see deleteRecursively(File).
    
    Parameters:
    
    prefix - The prefix string to be used in generating the file's name; see File.createTempFile(String, String, File)
    
    Returns:
    
    An abstract pathname denoting a newly-created empty directory
    
    Throws:
    
    IOException
  - createTemporaryDirectory
```
public static File createTemporaryDirectory(String prefix,
                                            String suffix)
                                     throws IOException
```
    Creates a temporary directory.
    Since there is no atomic operation to do that, we create a temporary file, delete it and create a directory in its place. To avoid race conditions, we use the optimistic approach: if the directory cannot be created, we try to obtain a new temporary file rather than erroring out.
    
    It is the caller's responsibility to make sure that the directory is deleted; see deleteRecursively(File).
    
    Parameters:
    
    prefix - The prefix string to be used in generating the file's name; see File.createTempFile(String, String, File)
    
    suffix - The suffix string to be used in generating the file's name; see File.createTempFile(String, String, File)
    
    Returns:
    
    An abstract pathname denoting a newly-created empty directory
    
    Throws:
    
    IOException
  - createTemporaryDirectory
```
public static File createTemporaryDirectory(String prefix,
                                            String suffix,
                                            File directory)
                                     throws IOException
```
    Creates a temporary directory.
    Since there is no atomic operation to do that, we create a temporary file, delete it and create a directory in its place. To avoid race conditions, we use the optimistic approach: if the directory cannot be created, we try to obtain a new temporary file rather than erroring out.
    
    It is the caller's responsibility to make sure that the directory is deleted; see deleteRecursively(File).
    
    Parameters:
    
    prefix - The prefix string to be used in generating the file's name; see File.createTempFile(String, String, File)
    
    suffix - The suffix string to be used in generating the file's name; see File.createTempFile(String, String, File)
    
    directory - The directory in which the file is to be created, or null if the default temporary-file directory is to be used
    
    Throws:
    
    IOException
  - deleteRecursively
```
public static boolean deleteRecursively(File directory)
```
    Deletes a directory recursively.
    
    Parameters:
    
    directory - The directory to delete.
    
    Returns:
    
    whether it succeeded (see also File.delete())
  - listContents
```
public static Collection<URL> listContents(URL directory)
```
    Recursively lists the contents of the referenced directory. Directories are excluded from the result. Supported protocols include file and jar.
    
    Parameters:
    
    directory - The directory whose contents should be listed.
    
    Returns:
    
    A collection of URLs representing the directory's contents.
    
    See Also:
    
    listContents(URL, boolean, boolean)
  - listContents
```
public static Collection<URL> listContents(URL directory,
                                           boolean recurse,
                                           boolean filesOnly)
```
    Lists all contents of the referenced directory. Supported protocols include file and jar.
    
    Parameters:
    
    directory - The directory whose contents should be listed.
    
    recurse - Whether to list contents recursively, as opposed to only the directory's direct contents.
    
    filesOnly - Whether to exclude directories in the resulting collection of contents.
    
    Returns:
    
    A collection of URLs representing the directory's contents.
  - appendContents
```
public static Collection<URL> appendContents(Collection<URL> result,
                                             URL directory)
```
    Recursively adds contents from the referenced directory to an existing collection. Directories are excluded from the result. Supported protocols include file and jar.
    
    Parameters:
    
    result - The collection to which contents should be added.
    
    directory - The directory whose contents should be listed.
    
    Returns:
    
    A collection of URLs representing the directory's contents.
    
    See Also:
    
    appendContents(Collection, URL, boolean, boolean)
  - appendContents
```
public static Collection<URL> appendContents(Collection<URL> result,
                                             URL directory,
                                             boolean recurse,
                                             boolean filesOnly)
```
    Add contents from the referenced directory to an existing collection. Supported protocols include file and jar.
    
    Parameters:
    
    result - The collection to which contents should be added.
    
    directory - The directory whose contents should be listed.
    
    recurse - Whether to append contents recursively, as opposed to only the directory's direct contents.
    
    filesOnly - Whether to exclude directories in the resulting collection of contents.
    
    Returns:
    
    A collection of URLs representing the directory's contents.
  - findResources
```
public static Map<String,URL> findResources(String regex,
                                            String pathPrefix,
                                            File baseDirectory)
```
    Finds URLs of available resources. Both JAR files and files on disk are searched, according to the following mechanism:
    1. Resources at the given pathPrefix are discovered using ClassLoader.getResources(String) with the current thread's context class loader. In particular, this invocation discovers resources in JAR files beneath the given pathPrefix.
    2. The directory named pathPrefix beneath the given baseDirectory is scanned last, so that users can more easily override resources provided inside JAR files by placing a resource of the same name within that directory.
    In both cases, resources are then recursively scanned using listContents(URL), and anything matching the given regex pattern is added to the output map.
    Parameters:
    
    regex - The regex to use when matching resources, or null to match everything.
    
    pathPrefix - The path to search for resources.
    
    baseDirectory - The baseDirectory/pathPrefix directory to scan after the URL resources.
    
    Returns:
    
    A map of URLs referencing the matched resources.
    
    See Also:
    
    AppUtils.getBaseDirectory(java.lang.String, java.lang.Class<?>, java.lang.String)
  - findResources
```
public static Map<String,URL> findResources(String regex,
                                            Iterable<URL> urls)
```
    Finds URLs of resources known to the system.
    Each of the given URLs is recursively scanned using listContents(URL), and anything matching the given regex pattern is added to the output map.
    
    Parameters:
    
    regex - The regex to use when matching resources, or null to match everything.
    
    urls - Paths to search for resources.
    
    Returns:
    
    A map of URLs referencing the matched resources.
  - matchVersionedFilename
```
@Deprecated
public static Matcher matchVersionedFilename(String filename)
```
    Deprecated. see stripFilenameVersion(String)
    
    Returns the Matcher object dissecting a versioned file name.
    
    Parameters:
    
    filename - the file name
    
    Returns:
    
    the Matcher object

Class FileUtils

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_SHORTENER_THRESHOLD

SHORTENER_BACKSLASH_REGEX

SHORTENER_SLASH_REGEX

SHORTENER_BACKSLASH

SHORTENER_SLASH

SHORTENER_ELLIPSE

Method Detail

getPath

getPath

getExtension

getExtension

getModifiedTime

readFile

writeFile

stripFilenameVersion

getAllVersions

urlToFile

urlToFile

shortenPath

shortenPath

limitPath

createTemporaryDirectory

createTemporaryDirectory

createTemporaryDirectory

deleteRecursively

listContents

listContents

appendContents

appendContents

findResources

findResources

matchVersionedFilename