Package de.sciss.io

Class IOUtil

  • public class IOUtil
extends java.lang.Object
    This is a helper class containing utility static functions for common file operations.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.lang.String KEY_TEMPDIR
      Value: String representing the pathname of the temporary files directory.
      Has default value: yes!
      Node: root

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static java.lang.String abbreviate​(java.lang.String fileName, int maxLen)
      Abbreviates a path name by replacing sub directories by an ellipsis character.
      static void createEmptyDirectory​(java.io.File f)
      Creates a new empty directory.
      static void createEmptyFile​(java.io.File f)
      Creates an empty file.
      static java.io.File createTempFile()
      Creates a new temporary file, using the preferred temp file folder (KEY_TEMPDIR).
      static java.io.File createTempFile​(java.lang.String prefix, java.lang.String suffix)
      Create a new temporary file with specified prefix and suffix.
      static void deleteAll​(java.io.File f)
      Deletes a file or directory.
      static java.lang.String getResourceString​(java.lang.String key)  
      static java.util.prefs.Preferences getUserPrefs()  
      static double getVersion()  
      static java.io.IOException map​(java.lang.Exception e)
      Input/output methods sometimes contain methods from other java API that throw exceptions which are not subclasses of IOException.
      static java.io.File nonExistentFileVariant​(java.io.File template, int insertPos, java.lang.String prefix, java.lang.String suffix)
      Iteratres a filename template as long as filenames generated by the template already exist.
      static java.io.File setFileSuffix​(java.io.File f, java.lang.String ext)
      Sets the extension (suffix) of a file name.

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • KEY_TEMPDIR

        public static final java.lang.String KEY_TEMPDIR
        Value: String representing the pathname of the temporary files directory.
        Has default value: yes!
        Node: root
        See Also:
        Constant Field Values

    • Method Detail

      • getUserPrefs

        public static final java.util.prefs.Preferences getUserPrefs()

      • getVersion

        public static final double getVersion()

      • getResourceString

        public static final java.lang.String getResourceString​(java.lang.String key)

      • map

        public static java.io.IOException map​(java.lang.Exception e)
        Input/output methods sometimes contain methods from other java API that throw exceptions which are not subclasses of IOException. The present a more consistent frontend to the caller of these methods, any exceptions can be simply mapped to IOException by creating a new IOException with the same message text as the original exception.

        For example, in PrefsUtil's toXML method, BackingStoreExceptions and DOMExceptions are caught and rethrown: 

          try {
      ...
  } catch( DOMException e1 ) {
      throw IOUtil.map( e1 );
  }
        Parameters:
        e - the original exception whose message is queries and copied to the returned exception.
        Returns:
        a newly created IOException with the message text and exception class name copied from the given original exception.

      • abbreviate

        public static java.lang.String abbreviate​(java.lang.String fileName,
                                          int maxLen)
        Abbreviates a path name by replacing sub directories by an ellipsis character. This is used inside MenuFactory to shorten the path names attached to the Open-Recent menu.
        Parameters:
        fileName - the pathName to abbreviate
        maxLen - maximum length of the Abbreviation. Beware: this method appends sub directories until maxLen is exceeded, therefore the returned String can well exceed maxLen!
        Returns:
        the abbreviated path name or the original path name if it was shorter or equal maxLen. It is guaranteed that the file name part of the path is fully included.

      • createEmptyDirectory

        public static void createEmptyDirectory​(java.io.File f)
                                 throws java.io.IOException
        Creates a new empty directory. If a file or directory of the specified name already exists it will be deleted.
        Parameters:
        f - pathname denoting the folder to create. this method will attempt to create nonexisting parent folders if required.
        Throws:
        java.io.IOException - is the directory cannot be created or emptied.
        See Also:
        deleteAll( File ), File.mkdirs()

      • createEmptyFile

        public static void createEmptyFile​(java.io.File f)
                            throws java.io.IOException
        Creates an empty file. If file denoted by f already exists, it will be erased.
        Parameters:
        f - the file to be erased
        Throws:
        java.io.IOException - if an error occurs such as the file being protected or indicating an invalid path

      • createTempFile

        public static java.io.File createTempFile()
                                   throws java.io.IOException
        Creates a new temporary file, using the preferred temp file folder (KEY_TEMPDIR). The file will automatically deleted upon application exit.
        Returns:
        the newly created temp file, suitable for passing to a RandomAccessFile constructor or similar.
        Throws:
        java.io.IOException - if this method fails to create the file
        See Also:
        File.createTempFile( String, String, File ), File.deleteOnExit(), KEY_TEMPDIR

      • createTempFile

        public static java.io.File createTempFile​(java.lang.String prefix,
                                          java.lang.String suffix)
                                   throws java.io.IOException
        Create a new temporary file with specified prefix and suffix. Suffix is allowed to be null in which case a default suffix (.tmp) is used.
        Parameters:
        prefix - string with which to filename shall begin, minimum three letters but as short as possible. might be truncated.
        suffix - string with which to filename shall end (including the period if used as a file type suffix). might be truncated, but if it begins with a period, the following three letters are guaranteed to be preserved.
        Returns:
        the newly created temp file, suitable for passing to a RandomAccessFile constructor or similar.
        Throws:
        java.io.IOException - if this method fails to create the file
        See Also:
        File.createTempFile( String, String, File ), File.deleteOnExit(), KEY_TEMPDIR

      • deleteAll

        public static void deleteAll​(java.io.File f)
                      throws java.io.IOException
        Deletes a file or directory. If the directory is not empty, all files and subfolders in the directory will be deleted recursively.
        Parameters:
        f - the path (file or folder) to delete
        Throws:
        java.io.IOException - if the deletion fails
        See Also:
        File.delete()

      • setFileSuffix

        public static java.io.File setFileSuffix​(java.io.File f,
                                         java.lang.String ext)
        Sets the extension (suffix) of a file name. If the provided path has already a suffix, it is replaced. Otherwise, the new suffix will be appended.
        Parameters:
        f - the file whose suffix to change. can be null in which case null is returned
        ext - the new suffix, e.g. ".aif", ".xml" etc. the leading period may be omitted. if ext is null, the suffix is removed.
        Returns:
        the newly composed file name or the original path, if path name didn't change

      • nonExistentFileVariant

        public static java.io.File nonExistentFileVariant​(java.io.File template,
                                                  int insertPos,
                                                  java.lang.String prefix,
                                                  java.lang.String suffix)
        Iteratres a filename template as long as filenames generated by the template already exist. This method returns the template if a file denoted by the template does not exist.

        Example: with template = new File( "/Users/schoko/myFile.aif" ), insertPos = -1 and prefix = " " (white space), the method will first check if file "/Users/schoko/myFile.aif" exists, if not that file will be returned. Next, it will check for the file "/Users/schoko/myFile 1.aif", then for "/Users/schoko/myFile 2.aif" etc.

        Parameters:
        template - template path
        insertPos - the index in the name portion of the template at which variants are to be inserted; if insertPos is -1, the position of the period of the file-type suffix will be used (and if not found, the end of the template).
        prefix - a string to paste before the inserted variant, can be null
        suffix - a string to paste after the inserted variant, can be null