Class FileUtils


  • public class FileUtils
    extends Object
    Some utilities for handling files.
    • Constructor Detail

      • FileUtils

        public FileUtils()
    • Method Detail

      • getFiles

        public static final ArrayList<File> getFiles​(File directory,
                                                     boolean getRecursive)
        Get a list of all files in a directory. Optionally, get files in subdirectories as well.
        Parameters:
        directory - The directory for which to get the files.
        getRecursive - Should we get files from subdirectories?
        Returns:
        ArrayList A list of File objects. null if directory does not exist, or is not a directory.
      • getFiles

        public static final ArrayList<File> getFiles​(File directory)
        Get a list of all files in a directory, ignoring subdirectories.
        Parameters:
        directory - The directory for which to get the files.
        Returns:
        ArrayList A list of File objects. null if directory does not exist, or is not a directory.
      • getSubDirs

        public static final ArrayList<File> getSubDirs​(File directory)
        Get a list of all subdirectories in a directory, ignoring regular files.
        Parameters:
        directory - The directory for which to get the subdirectories.
        Returns:
        ArrayList A list of File objects. null if directory does not exist, or is not a directory.
      • reader2String

        public static String reader2String​(Reader reader)
                                    throws IOException
        Read a bufferedReader into a string, using the default platform encoding.
        Parameters:
        reader - to be read in
        Returns:
        String The contents of the stream.
        Throws:
        IOException - Various I/O errors.
      • file2String

        public static String file2String​(File file)
                                  throws IOException
        Read the contents of a file into a string, using the default platform encoding.
        Parameters:
        file - The file to be read in.
        Returns:
        String The contents of the file.
        Throws:
        IOException - Various I/O errors.
      • file2String

        public static String file2String​(File file,
                                         String fileEncoding)
                                  throws IOException
        Read the contents of a file into a string using a specific character encoding.
        Parameters:
        file - The input file.
        fileEncoding - The character encoding of the file (see your Java documentation for supported encodings).
        Returns:
        String The contents of the file.
        Throws:
        IOException - Various I/O errors.
      • saveString2File

        public static void saveString2File​(String fileContents,
                                           File file)
                                    throws IOException
        Write a string to a file, using platform encoding. If the file exists, it is overwritten.
        Parameters:
        fileContents - The file contents.
        file - The file to save to.
        Throws:
        IOException - If for any reason the file can't be written.
      • saveString2File

        public static void saveString2File​(String s,
                                           File file,
                                           String encoding)
                                    throws IOException
        Write a string to a file using the specified encoding. If the file exists, it is overwritten.
        Parameters:
        s - The file contents.
        file - The file to save to.
        encoding - The character encoding to use.
        Throws:
        IOException - If for any reason the file can't be written.
      • deleteAllFiles

        public static final void deleteAllFiles​(File directory)
        Delete all files in a directory (not recursive).
        Parameters:
        directory - The directory that contains the files to be deleted.
      • deleteRecursive

        public static final boolean deleteRecursive​(File file)
        Recursively delete possibly non-empty directory or file.
        Parameters:
        file - The file or directory to be deleted.
        Returns:
        true iff the file/directory could be deleted.
      • mkdir

        public static final boolean mkdir​(File directory)
        Create a new directory. The parent directory must exist.
        Parameters:
        directory - The directory to be created.
        Returns:
        boolean Will fail if directory already exists, or File.mkdir() returns false.
      • createTempDir

        public static final File createTempDir​(File parent,
                                               String prefix)
        Create a temporary directory using random numbers as name suffixes.
        Parameters:
        parent - Where the directory is created.
        prefix - Prefix of the directory names to be created.
        Returns:
        A file object corresponding to the newly created dir, or null if none could be created for some reason (e.g., if the parent is not writable).
      • copyFile

        public static final void copyFile​(File file,
                                          File dir)
                                   throws IOException
        Copy file file to location dir. This method will not fail silently. Anything that prevents the copy from happening will be treated as an error condition. If the method does not throw an exception, the copy was successful.

        Note: this is a completely brain-dead implementation of file copy. The complete file is read into memory before it is copied. If you need something more sophisticated for copying large files, feel free to add your improvements.

        Parameters:
        file - The file to copy.
        dir - The destination directory.
        Throws:
        IOException - For various reason: if file does not exist or is not readable, if the destination directory does not exist or isn't a directory, or if the file can't be copied for any reason.
      • findRelativePath

        public static String findRelativePath​(File file,
                                              File relativeToDir)
                                       throws IOException
        Finds a relative path to a given file, relative to a specified directory.
        Parameters:
        file - file that the relative path should resolve to
        relativeToDir - directory that the path should be relative to
        Returns:
        a relative path. This always uses / as the separator character.
        Throws:
        IOException - -
      • getPathComponents

        public static String[] getPathComponents​(String canonicalPath)
        Splits a path into components using the OS file separator character. This can be used on the results of File.getCanonicalPath().
        Parameters:
        canonicalPath - a file path that uses the OS file separator character
        Returns:
        an array of strings, one for each component of the path