Package com.norconex.commons.lang.file

Class FileUtil

java.lang.Object
com.norconex.commons.lang.file.FileUtil
public final class FileUtil extends Object
Utility methods when dealing with files and directories.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final File[]
    EMPTY_FILE_ARRAY
     
    static final Path[]
    EMPTY_PATH_ARRAY
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static File
    createDateDirs(File parentDir)
    Creates (if not already existing) a series of directories reflecting the current date, up to the day unit, under a given parent directory.
    static File
    createDateDirs(File parentDir, Date date)
    Creates (if not already existing) a series of directories reflecting a date, up to the day unit, under a given parent directory.
    static File
    createDateFormattedDirs(@NonNull File parentDir, @NonNull Date dateTime, String format)
    Creates (if not already existing) a series of directories reflecting the specified date format (from SimpleDateFormat), under a given parent directory.
    static File
    createDateTimeDirs(File parentDir)
    Creates (if not already existing) a series of directories reflecting the current date and time, up to the seconds, under a given parent directory.
    static File
    createDateTimeDirs(File parentDir, Date dateTime)
    Creates (if not already existing) a series of directories reflecting a date and time, up to the seconds, under a given parent directory.
    static File
    createDirsForFile(File file)
    Create all parent directories for a file if they do not exists.
    static File
    createURLDirs(@NonNull File parentDir, @NonNull String url, boolean truncate)
    Creates (if not already existing) a series of directories matching URL segments, under a given parent directory.
    static File
    createURLDirs(File parentDir, String url)
    Creates (if not already existing) a series of directories matching URL segments, under a given parent directory.
    static File
    createURLDirs(File parentDir, URL url)
    Creates (if not already existing) a series of directories matching URL segments, under a given parent directory.
    static File
    createURLDirs(File parentDir, URL url, boolean truncate)
    Creates (if not already existing) a series of directories matching URL segments, under a given parent directory.
    static void
    delete(File file)
    Deletes a file or empty directory recursively, in a more robust way.
    static int
    deleteEmptyDirs(File parentDir)
    Recursively deletes all empty directories.
    static int
    deleteEmptyDirs(File parentDir, Date date)
    Recursively deletes all directories that are empty and are older than the given date.
    static int
    deleteEmptyDirs(Path parentDir)
    Recursively deletes all empty directories.
    static int
    deleteEmptyDirs(Path parentDir, Date date)
    Recursively deletes all directories that are empty and are older than the given date.
    static boolean
    dirEmpty(File dir)
    Gets whether a directory is empty of files or directories in an efficient way which does not load all files.
    static boolean
    dirEmpty(Path dir)
    Gets whether a directory is empty of files or directories in an efficient way which does not load all files.
    static boolean
    dirHasFile(File dir, FileFilter filter)
    Recursively gets whether a directory contains at least one file matching the given file filter.
    static boolean
    dirHasFile(Path dir, FileFilter filter)
    Recursively gets whether a directory contains at least one file matching the given file filter.
    static String
    fromSafeFileName(String safeFileName)
    Converts a "safe" file name originally created with toSafeFileName(String) into its original string.
    static String[]
    head(File file, int numberOfLinesToRead)
    Returns the specified number of lines starting from the beginning of a text file.
    static String[]
    head(File file, String encoding, int numberOfLinesToRead)
    Returns the specified number of lines starting from the beginning of a text file, using the given encoding.
    static String[]
    head(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines)
    Returns the specified number of lines starting from the beginning of a text file, using the given encoding.
    static String[]
    head(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines, Predicate<String> filter)
    Returns the specified number of lines starting from the beginning of a text file, using the given encoding.
    static boolean
    isDirectory(File dir)
    Null-safe alternative to Files.isDirectory(Path, java.nio.file.LinkOption...) A null directory always returns false.
    static boolean
    isDirectory(Path dir)
    Null-safe alternative to Files.isDirectory(Path, java.nio.file.LinkOption...) A null directory always returns false.
    static boolean
    isFile(File file)
    Null-safe alternative to File.isFile().
    static boolean
    isFile(Path file)
    Null-safe alternative to Files.isRegularFile(Path, java.nio.file.LinkOption...).
    static void
    moveFile(@NonNull File sourceFile, @NonNull File targetFile)
    Moves a file to a new file location.
    static void
    moveFile(@NonNull Path sourceFile, @NonNull Path targetFile)
    Moves a file to a new file location.
    static File
    moveFileToDir(@NonNull File sourceFile, @NonNull File targetDir)
    Moves a file to a directory.
    static Path
    moveFileToDir(@NonNull Path sourceFile, @NonNull Path targetDir)
    Moves a file to a directory.
    static String[]
    tail(File file, int numberOfLinesToRead)
    Returns the specified number of lines starting from the end of a text file.
    static String[]
    tail(File file, String encoding, int numberOfLinesToRead)
    Returns the specified number of lines starting from the end of a text file.
    static String[]
    tail(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines)
    Returns the specified number of lines starting from the end of a text file.
    static String[]
    tail(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines, Predicate<String> filter)
    Returns the specified number of lines starting from the end of a text file.
    static File
    toDateFormattedDir(@NonNull File parentDir, @NonNull Date dateTime, String format)
    Gets (but does not create) a series of directories reflecting the specified date format (from SimpleDateFormat), under a given parent directory.
    static Path
    toPath(File file)
    Null-safe alternative to File.toPath().
    static Path[]
    toPaths(File[] files)
    Converts all supplied files to Path (null entries remain null).
    static List<Path>
    toPaths(Collection<File> files)
    Converts all supplied files to Path (null entries remain null).
    static String
    toSafeFileName(String unsafeFileName)
    Converts any String to a valid file-system file name representation.
    static File
    toURLDir(@NonNull File parentDir, @NonNull String url, boolean truncate)
    Gets (but does not create) a directory matching URL segments, under a given parent directory.
    static File
    toURLDir(@NonNull File parentDir, @NonNull URL url, boolean truncate)
    Gets (but does not create) a directory matching URL segments, under a given parent directory.
    static File
    toURLDir(File parentDir, String url)
    Gets (but does not create) a directory matching URL segments, under a given parent directory.
    static File
    toURLDir(File parentDir, URL url)
    Gets (but does not create) a directory matching URL segments, under a given parent directory.
    static void
    visitAllDirs(File dir, FileVisitor visitor)
    Visits only directories under a directory.
    static void
    visitAllDirs(File dir, FileVisitor visitor, FileFilter filter)
    Visits only directories under a directory.
    static void
    visitAllDirsAndFiles(File dir, FileVisitor visitor)
    Visits all files and directories under a directory.
    static void
    visitAllDirsAndFiles(File dir, FileVisitor visitor, FileFilter filter)
    Visits all files and directories under a directory.
    static void
    visitAllFiles(File dir, FileVisitor visitor)
    Visits all files (and only files) under a directory, including sub-directories.
    static void
    visitAllFiles(File dir, FileVisitor visitor, FileFilter filter)
    Visits all files (and only files) under a directory, including sub-directories.
    static void
    visitEmptyDirs(File dir, FileVisitor visitor)
    Visits only empty directories under a directory.
    static void
    visitEmptyDirs(File dir, FileVisitor visitor, FileFilter filter)
    Visits only empty directories under a directory.

    Methods inherited from class java.lang.Object

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

  • Field Details

    • EMPTY_PATH_ARRAY

      public static final Path[] EMPTY_PATH_ARRAY
      Since:
      3.0.0

    • EMPTY_FILE_ARRAY

      public static final File[] EMPTY_FILE_ARRAY
      Since:
      3.0.0

  • Method Details

    • dirEmpty

      public static boolean dirEmpty(File dir) throws IOException
      Gets whether a directory is empty of files or directories in an efficient way which does not load all files. The directory must exist and be a valid directory (e.g., not a file).
      Parameters:
      dir - the directory to check for emptiness
      Returns:
      true if directory exists and is empty
      Throws:
      IOException - if an I/O error occurs
      Since:
      2.0.0

    • dirEmpty

      public static boolean dirEmpty(Path dir) throws IOException
      Gets whether a directory is empty of files or directories in an efficient way which does not load all files. The directory must exist and be a valid directory (e.g., not a file).
      Parameters:
      dir - the directory to check for emptiness
      Returns:
      true if directory exists and is empty
      Throws:
      IOException - if an I/O error occurs
      Since:
      3.0.0

    • dirHasFile

      public static boolean dirHasFile(File dir, FileFilter filter) throws IOException
      Recursively gets whether a directory contains at least one file matching the given file filter.
      Parameters:
      dir - directory to inspect
      filter - file or directory filter
      Returns:
      true upon filter matching a file or directory
      Throws:
      IOException - if an I/O error occurs

    • dirHasFile

      public static boolean dirHasFile(Path dir, FileFilter filter) throws IOException
      Recursively gets whether a directory contains at least one file matching the given file filter.
      Parameters:
      dir - directory to inspect
      filter - file or directory filter
      Returns:
      true upon filter matching a file or directory
      Throws:
      IOException - if an I/O error occurs
      Since:
      3.0.0

    • toSafeFileName

      public static String toSafeFileName(String unsafeFileName)
      Converts any String to a valid file-system file name representation. The valid file name is constructed so it can be written to virtually any operating system. It will escape every characters that are not alphanumeric, hyphen, or dot. Use fromSafeFileName(String) to get back the original name.
      Parameters:
      unsafeFileName - the file name to make safe.
      Returns:
      valid file name

    • fromSafeFileName

      public static String fromSafeFileName(String safeFileName)
      Converts a "safe" file name originally created with toSafeFileName(String) into its original string.
      Parameters:
      safeFileName - the file name to convert to its original form
      Returns:
      original string

    • moveFileToDir

      public static File moveFileToDir(@NonNull @NonNull File sourceFile, @NonNull @NonNull File targetDir) throws IOException
      Moves a file to a directory. Like moveFile(File, File):
      • If the target directory does not exists, it creates it first.
      • If the target file already exists, it deletes it first.
      • If target file deletion does not work, it will try 10 times, waiting half a second between each try to give a chance to whatever OS lock on the file to go.
      • It throws a IOException if the move failed (as opposed to fail silently).
      Parameters:
      sourceFile - source file to move
      targetDir - target destination
      Returns:
      new location of moved file (since 3.0.0)
      Throws:
      IOException - cannot move file.

    • moveFileToDir

      public static Path moveFileToDir(@NonNull @NonNull Path sourceFile, @NonNull @NonNull Path targetDir) throws IOException
      Moves a file to a directory. Like moveFile(File, File):
      • If the target directory does not exists, it creates it first.
      • If the target file already exists, it deletes it first.
      • If target file deletion does not work, it will try 10 times, waiting half a second between each try to give a chance to whatever OS lock on the file to go.
      • It throws a IOException if the move failed (as opposed to fail silently).
      Parameters:
      sourceFile - source file to move
      targetDir - target destination
      Returns:
      new location of moved file
      Throws:
      IOException - cannot move file.
      Since:
      3.0.0

    • moveFile

      public static void moveFile(@NonNull @NonNull File sourceFile, @NonNull @NonNull File targetFile) throws IOException
      Moves a file to a new file location. This method is different from the File.renameTo(File) method in such that:
      • If the target file already exists, it deletes it first.
      • If target file deletion does not work, it will try 10 times, waiting half a second between each try to give a chance to whatever OS lock on the file to go.
      • It throws a IOException if the move failed (as opposed to fail silently).
      • Since 3.0.0, it attempts to create any missing directories in the target path.
      Parameters:
      sourceFile - source file to move
      targetFile - target destination
      Throws:
      IOException - cannot move file.

    • moveFile

      public static void moveFile(@NonNull @NonNull Path sourceFile, @NonNull @NonNull Path targetFile) throws IOException
      Moves a file to a new file location. This method is different from the File.renameTo(File) method in such that:
      • If the target file already exists, it deletes it first.
      • If target file deletion does not work, it will try 10 times, waiting half a second between each try to give a chance to whatever OS lock on the file to go.
      • It throws a IOException if the move failed (as opposed to fail silently).
      • It attempts to create any missing directories in the target path.
      Parameters:
      sourceFile - source file to move
      targetFile - target destination
      Throws:
      IOException - cannot move file.
      Since:
      3.0.0

    • delete

      public static void delete(File file) throws IOException
      Deletes a file or empty directory recursively, in a more robust way. This method applies the following strategies:
      • If file or directory deletion does not work, it will re-try 10 times, waiting 1 second between each try to give a chance to whatever OS lock on the file to go.
      • After a first failed attempt, it invokes System.gc() in hope of releasing any handles left on files. This is in relation to a known Java bug mostly occurring on Windows (http://bugs.java.com/bugdatabase/view_bug.do?bug_id=4715154).
      • It throws a IOException if the delete still fails after the 10 attempts (as opposed to fail silently).
      • If file is null or does not exist, nothing happens.
      Parameters:
      file - file or directory to delete
      Throws:
      IOException - cannot delete file.
      Since:
      1.4. Renamed from deleteFile(File)

    • deleteEmptyDirs

      public static int deleteEmptyDirs(File parentDir) throws IOException
      Recursively deletes all empty directories. The supplied directory itself is also considered for deletion. Directories containing only empty child directories (and no files) are also considered empty and will be deleted.
      Parameters:
      parentDir - the directory where to start looking for empty directories
      Returns:
      the number of deleted directories
      Throws:
      IOException - error occurred deleting empty directories

    • deleteEmptyDirs

      public static int deleteEmptyDirs(Path parentDir) throws IOException
      Recursively deletes all empty directories. The supplied directory itself is also considered for deletion. Directories containing only empty child directories (and no files) are also considered empty and will be deleted.
      Parameters:
      parentDir - the directory where to start looking for empty directories
      Returns:
      the number of deleted directories
      Throws:
      IOException - error occurred deleting empty directories

    • deleteEmptyDirs

      public static int deleteEmptyDirs(File parentDir, Date date) throws IOException

      Recursively deletes all directories that are empty and are older than the given date. If the date is null, all empty directories will be deleted, regardless of their date. The supplied directory itself is also considered for deletion.

      Since 3.0.0, directories containing only empty child directories (and no files) are also considered empty and will be deleted.

      Parameters:
      parentDir - the directory where to start looking for empty directories
      date - the date to compare empty directories against
      Returns:
      the number of deleted directories
      Throws:
      IOException - error occurred deleting empty directories
      Since:
      1.3.0

    • deleteEmptyDirs

      public static int deleteEmptyDirs(Path parentDir, Date date) throws IOException
      Recursively deletes all directories that are empty and are older than the given date. If the date is null, all empty directories will be deleted, regardless of their date. The supplied directory itself is also considered for deletion. Directories containing only empty child directories (and no files) are also considered empty and will be deleted.
      Parameters:
      parentDir - the directory where to start looking for empty directories
      date - the date to compare empty directories against
      Returns:
      the number of deleted directories
      Throws:
      IOException - error occurred deleting empty directories
      Since:
      3.0.0

    • createDirsForFile

      public static File createDirsForFile(File file) throws IOException
      Create all parent directories for a file if they do not exists. If they exist already, this method does nothing. This method assumes the last segment is a file or will be a file.
      Parameters:
      file - the file to create parent directories for
      Returns:
      The newly created parent directory
      Throws:
      IOException - if something went wrong creating the parent directories

    • visitAllDirsAndFiles

      public static void visitAllDirsAndFiles(File dir, FileVisitor visitor)
      Visits all files and directories under a directory.
      Parameters:
      dir - the directory
      visitor - the visitor

    • visitAllDirsAndFiles

      public static void visitAllDirsAndFiles(File dir, FileVisitor visitor, FileFilter filter)
      Visits all files and directories under a directory.
      Parameters:
      dir - the directory
      visitor - the visitor
      filter - an optional filter to restrict the files being visited

    • visitEmptyDirs

      public static void visitEmptyDirs(File dir, FileVisitor visitor)
      Visits only empty directories under a directory.
      Parameters:
      dir - the directory
      visitor - the visitor
      Since:
      1.3.0

    • visitEmptyDirs

      public static void visitEmptyDirs(File dir, FileVisitor visitor, FileFilter filter)
      Visits only empty directories under a directory.
      Parameters:
      dir - the directory
      visitor - the visitor
      filter - an optional filter to restrict the visited directories
      Since:
      1.3.0

    • visitAllDirs

      public static void visitAllDirs(File dir, FileVisitor visitor)
      Visits only directories under a directory.
      Parameters:
      dir - the directory
      visitor - the visitor

    • visitAllDirs

      public static void visitAllDirs(File dir, FileVisitor visitor, FileFilter filter)
      Visits only directories under a directory.
      Parameters:
      dir - the directory
      visitor - the visitor
      filter - an optional filter to restrict the visited directories
      Since:
      1.3.0

    • visitAllFiles

      public static void visitAllFiles(File dir, FileVisitor visitor)
      Visits all files (and only files) under a directory, including sub-directories.
      Parameters:
      dir - the directory
      visitor - the visitor

    • visitAllFiles

      public static void visitAllFiles(File dir, FileVisitor visitor, FileFilter filter)
      Visits all files (and only files) under a directory, including sub-directories.
      Parameters:
      dir - the directory
      visitor - the visitor
      filter - an optional filter to restrict the files being visited

    • head

      public static String[] head(File file, int numberOfLinesToRead) throws IOException
      Returns the specified number of lines starting from the beginning of a text file. Since 1.5.0, UTF-8 is used as the default encoding.
      Parameters:
      file - the file to read lines from
      numberOfLinesToRead - the number of lines to read
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • head

      public static String[] head(File file, String encoding, int numberOfLinesToRead) throws IOException
      Returns the specified number of lines starting from the beginning of a text file, using the given encoding.
      Parameters:
      file - the file to read lines from
      encoding - the file encoding
      numberOfLinesToRead - the number of lines to read
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • head

      public static String[] head(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines) throws IOException
      Returns the specified number of lines starting from the beginning of a text file, using the given encoding.
      Parameters:
      file - the file to read lines from
      encoding - the file encoding
      numberOfLinesToRead - the number of lines to read
      stripBlankLines - whether to return blank lines or not
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • head

      public static String[] head(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines, Predicate<String> filter) throws IOException
      Returns the specified number of lines starting from the beginning of a text file, using the given encoding.
      Parameters:
      file - the file to read lines from
      encoding - the file encoding
      numberOfLinesToRead - the number of lines to read
      stripBlankLines - whether to return blank lines or not
      filter - InputStream filter
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • tail

      public static String[] tail(File file, int numberOfLinesToRead) throws IOException
      Returns the specified number of lines starting from the end of a text file. Since 1.5.0, UTF-8 is used as the default encoding.
      Parameters:
      file - the file to read lines from
      numberOfLinesToRead - the number of lines to read
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • tail

      public static String[] tail(File file, String encoding, int numberOfLinesToRead) throws IOException
      Returns the specified number of lines starting from the end of a text file.
      Parameters:
      file - the file to read lines from
      encoding - the file encoding
      numberOfLinesToRead - the number of lines to read
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • tail

      public static String[] tail(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines) throws IOException
      Returns the specified number of lines starting from the end of a text file.
      Parameters:
      file - the file to read lines from
      encoding - the file encoding
      numberOfLinesToRead - the number of lines to read
      stripBlankLines - whether to return blank lines or not
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • tail

      public static String[] tail(File file, String encoding, int numberOfLinesToRead, boolean stripBlankLines, Predicate<String> filter) throws IOException
      Returns the specified number of lines starting from the end of a text file.
      Parameters:
      file - the file to read lines from
      encoding - the file encoding
      numberOfLinesToRead - the number of lines to read
      stripBlankLines - whether to return blank lines or not
      filter - InputStream filter
      Returns:
      array of file lines
      Throws:
      IOException - i/o problem

    • createDateDirs

      public static File createDateDirs(File parentDir) throws IOException
      Creates (if not already existing) a series of directories reflecting the current date, up to the day unit, under a given parent directory. For example, a date of 2000-12-31 will create the following directory structure: /<parentDir>/2000/12/31/
      Parameters:
      parentDir - the parent directory where to create date directories
      Returns:
      the directory representing the full path created
      Throws:
      IOException - if the parent directory is not valid

    • createDateDirs

      public static File createDateDirs(File parentDir, Date date) throws IOException
      Creates (if not already existing) a series of directories reflecting a date, up to the day unit, under a given parent directory. For example, a date of 2000-12-31 will create the following directory structure: /<parentDir>/2000/12/31/
      Parameters:
      parentDir - the parent directory where to create date directories
      date - the date to create directories from
      Returns:
      the directory representing the full path created
      Throws:
      IOException - if the parent directory is not valid

    • createDateTimeDirs

      public static File createDateTimeDirs(File parentDir) throws IOException
      Creates (if not already existing) a series of directories reflecting the current date and time, up to the seconds, under a given parent directory. For example, a date of 2000-12-31T13:34:12 will create the following directory structure: /<parentDir>/2000/12/31/13/34/12/
      Parameters:
      parentDir - the parent directory where to create date directories
      Returns:
      the directory representing the full path created
      Throws:
      IOException - if the parent directory is not valid

    • createDateTimeDirs

      public static File createDateTimeDirs(File parentDir, Date dateTime) throws IOException
      Creates (if not already existing) a series of directories reflecting a date and time, up to the seconds, under a given parent directory. For example, a date of 2000-12-31T13:34:12 will create the following directory structure: /<parentDir>/2000/12/31/13/34/12/
      Parameters:
      parentDir - the parent directory where to create date directories
      dateTime - the date to create directories from
      Returns:
      the directory representing the full path created
      Throws:
      IOException - if the parent directory is not valid

    • createDateFormattedDirs

      public static File createDateFormattedDirs(@NonNull @NonNull File parentDir, @NonNull @NonNull Date dateTime, String format) throws IOException
      Creates (if not already existing) a series of directories reflecting the specified date format (from SimpleDateFormat), under a given parent directory. Use forward slash in your date format for creating sub-directories. For example, a date of 2000-12-31T13:34:12 with a format of yyyy/MM/dd/HH-mm-ss will create the following directory structure: /<parentDir>/2000/12/31/13-34-12/
      Parameters:
      parentDir - the parent directory where to create date directories
      dateTime - the date to create directories from
      format - the format to use for creating a date-formatted directory
      Returns:
      the directory representing the full path created
      Throws:
      IOException - if the parent directory is not valid
      Since:
      2.0.0

    • toDateFormattedDir

      public static File toDateFormattedDir(@NonNull @NonNull File parentDir, @NonNull @NonNull Date dateTime, String format)
      Gets (but does not create) a series of directories reflecting the specified date format (from SimpleDateFormat), under a given parent directory. Use forward slash in your date format for creating sub-directories. For example, a date of 2000-12-31T13:34:12 with a format of yyyy/MM/dd/HH-mm-ss will create the following directory structure: /<parentDir>/2000/12/31/13-34-12/
      Parameters:
      parentDir - the parent directory where to create date directories
      dateTime - the date to create directories from
      format - the format to use for creating a date-formatted directory
      Returns:
      the directory representing the full path created
      Since:
      2.0.0

    • createURLDirs

      public static File createURLDirs(File parentDir, URL url) throws IOException

      Creates (if not already existing) a series of directories matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name (not created). The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly.

      Warning: the path created may be too long for some file systems. To avoid issues with file names being too long, consider truncating the generated path by using createURLDirs(File, URL, boolean) instead.

      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      Returns:
      the directory representing the full path created, plus file name
      Throws:
      IOException - if the parent directory is not valid

    • createURLDirs

      public static File createURLDirs(File parentDir, String url) throws IOException

      Creates (if not already existing) a series of directories matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name (not created). The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly.

      Warning: the path created may be too long for some file systems. To avoid issues with file names being too long, consider truncating the generated path by using createURLDirs(File, URL, boolean) instead.

      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      Returns:
      the directory representing the full path created, plus file name
      Throws:
      IOException - if the parent directory is not valid

    • createURLDirs

      public static File createURLDirs(File parentDir, URL url, boolean truncate) throws IOException
      Creates (if not already existing) a series of directories matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name (not created). The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly. For the same reason, the full path created can be truncated with a hash code if more than 255 characters. When truncating, the full path to the parent directory must be 200 or less characters (to leave some room for the URL path).
      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      truncate - whether to truncate the directory to 255 characters max.
      Returns:
      the directory representing the full path created, plus file name
      Throws:
      IOException - if the parent directory is not valid

    • createURLDirs

      public static File createURLDirs(@NonNull @NonNull File parentDir, @NonNull @NonNull String url, boolean truncate) throws IOException
      Creates (if not already existing) a series of directories matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name (not created). The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly. For the same reason, the full path created can be truncated with a hash code if more than 255 characters. When truncating, the full path to the parent directory must be 200 or less characters (to leave some room for the URL path).
      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      truncate - whether to truncate the directory to 255 characters max.
      Returns:
      the directory representing the full path created, plus file name
      Throws:
      IOException - if the parent directory is not valid

    • toURLDir

      public static File toURLDir(File parentDir, URL url)

      Gets (but does not create) a directory matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name. The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly.

      Warning: the path created may be too long for some file systems. To avoid issues with file names being too long, consider truncating the generated path by using toURLDir(File, URL, boolean) instead.

      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      Returns:
      the directory representing the full path created, plus file name
      Since:
      2.0.0

    • toURLDir

      public static File toURLDir(File parentDir, String url)

      Gets (but does not create) a directory matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name. The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly.

      Warning: the path created may be too long for some file systems. To avoid issues with file names being too long, consider truncating the generated path by using toURLDir(File, URL, boolean) instead.

      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      Returns:
      the directory representing the full path created, plus file name
      Since:
      2.0.0

    • toURLDir

      public static File toURLDir(@NonNull @NonNull File parentDir, @NonNull @NonNull URL url, boolean truncate)
      Gets (but does not create) a directory matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name. The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly. For the same reason, the full path created can be truncated with a hash code if more than 255 characters. When truncating, the full path to the parent directory must be 200 or less characters (to leave some room for the URL path).
      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      truncate - whether to truncate the directory to 255 characters max.
      Returns:
      the directory representing the full path created, plus file name
      Since:
      2.0.0

    • isFile

      public static boolean isFile(File file)
      Null-safe alternative to File.isFile(). A null file always returns false.
      Parameters:
      file - the file to test
      Returns:
      true if the file is not null, exists, and is a regular file
      Since:
      3.0.0

    • isFile

      public static boolean isFile(Path file)
      Null-safe alternative to Files.isRegularFile(Path, java.nio.file.LinkOption...). A null file always returns false.
      Parameters:
      file - the file to test
      Returns:
      true if the file is not null, exists, and is a regular file
      Since:
      3.0.0

    • isDirectory

      public static boolean isDirectory(File dir)
      Null-safe alternative to Files.isDirectory(Path, java.nio.file.LinkOption...) A null directory always returns false.
      Parameters:
      dir - the directory to test
      Returns:
      true if the directory is not null, exists, and is a directory
      Since:
      3.0.0

    • isDirectory

      public static boolean isDirectory(Path dir)
      Null-safe alternative to Files.isDirectory(Path, java.nio.file.LinkOption...) A null directory always returns false.
      Parameters:
      dir - the directory to test
      Returns:
      true if the directory is not null, exists, and is a directory
      Since:
      3.0.0

    • toPath

      public static Path toPath(File file)
      Null-safe alternative to File.toPath(). A null file returns null.
      Parameters:
      file - the file to convert
      Returns:
      a Path or null if file is null
      Since:
      3.0.0

    • toPaths

      public static Path[] toPaths(File[] files)
      Converts all supplied files to Path (null entries remain null).
      Parameters:
      files - the files to convert
      Returns:
      an array of Path, never null
      Since:
      3.0.0

    • toPaths

      public static List<Path> toPaths(Collection<File> files)
      Converts all supplied files to Path (null entries remain null).
      Parameters:
      files - the files to convert
      Returns:
      a list of Path, never null
      Since:
      3.0.0

    • toURLDir

      public static File toURLDir(@NonNull @NonNull File parentDir, @NonNull @NonNull String url, boolean truncate)
      Gets (but does not create) a directory matching URL segments, under a given parent directory. The returned file contains the full path to the directories, plus the file name. The file name is the last URL segment (including query string and fragment). Non-alphanumeric characters are escaped to be file-system-friendly. For the same reason, the full path created can be truncated with a hash code if more than 255 characters. When truncating, the full path to the parent directory must be 200 or less characters (to leave some room for the URL path).
      Parameters:
      parentDir - the parent directory where to create URL directories
      url - the URL to create directories for, with file name.
      truncate - whether to truncate the directory to 255 characters max.
      Returns:
      the directory representing the full path created, plus file name
      Since:
      2.0.0