Package org.marketcetera.util.file

Miscellaneous utilities for file management.

This package complements the standard Java file handling facilities and apache's IOUtils. These include:

• The CopyBytesUtils, CopyCharsUtils, and CopyCharsUnicodeUtils classes provide utilities for copying data between files, streams, and memory, in various combinations.

• FileType offers symbolic link detection and file typing, in the minimal fashion possible within the platform-independent Java.

• SmartLinksDirectoryWalker offers recursive file tree traversal and Deleter offers tree deletion; both are sensitive to symbolic links.

In addition to utilities, the package makes available a recommended design pattern for handling streams safely via the supporting class CloseableRegistry. When a series of streams need to be opened and eventually closed, it is important that such closures takes place in a timely fashion via explicit calls to close(). This must happen even if an exception interrupts normal processing, to ensure that the operating system does not maintain locks on unused files or uses up file descriptors. Here is the recommended approach for handling stream closure:

CloseableRegistry r=new CloseableRegistry();
try {
  ByteArrayOutputStream byteArray=new ByteArrayOutputStream();
  r.register(byteArray);
  PrintStream printStream=new PrintStream(byteArray);
  r.register(printStream);
  ... use printStream
} finally {
  r.close();
}

Many of the above utilities recognize sentinel values as input or output file names, such as :stdin: for standard input; the complete set of such special names is the constants of SpecialNames.

Interface Summary

Interface	Description
Messages	The internationalization constants used by this package.
SpecialNames	Special names used to denote standard streams or operations on regular files.

Class Summary

Class	Description
CloseableRegistry	A registry of Closeable instances.
CopyBytesUtils	Utilities for copying binary data.
CopyCharsUnicodeUtils	Utilities for copying textual data, with Unicode BOM support.
CopyCharsUtils	Utilities for copying textual data, in the default JVM charset.
Deleter	Deletes a file or directory recursively.
Deleter.RecursiveDeleter	A SmartLinksDirectoryWalker that does not follow symbolic links, and deletes all files it traverses.
InputStreamWrapper	A wrapped input stream.
OutputStreamWrapper	A wrapped output stream.
ReaderWrapper	A wrapped reader.
SmartLinksDirectoryWalker	A DirectoryWalker which provides convenience methods to initiate traversal, and (optionally) does not follow symbolic links.
WriterWrapper	A wrapped writer.

Enum Summary

Enum	Description
FileType	A file type.