DataFile

DataFile - master class for managing data files

Shane P. McCarron <shane@aptest.com>

Copyright 2001-2006 Applied Testing and Technology, Inc. All Rights Reserved.

use DataFile;

# create a new DataFile object
my $file = new DataFile(path, readwrite, timeout);

# update an object
$status = $file->save();

# release the object, unlocking it
$status = $file->release();

The DataFile class is a template class that manages accessing files composed of arbitrary data. The files can be in either serialized object format or in DBM file format. The methods in this class are expected to be extended in sub-classes that manage the data in the "data" attribute, and also manage any specialized attributes outside of the "data" attribute.

The data structure of this object is optimized to be most efficient when used in conjunction with MLDBM and a single key hashed database. This object CAN use serialized objects as well, but it is MUCH slower. Note that when using MLDBM, the save method doesn't do anything (except possibly for the first time it is called if the database had not yet been converted to MLDBM format).

lock

a handle to the locked "lockfile" that is set for the object.

writeable

a boolean that indicates whether the datafile is open read/write

usingDBM

a boolean to indicate if the file is from a DBM source

DBMhandle

a handle to the active, TIEd DBM file. This can be used by sub-classes to flush out the file, for example. NOTE: classes that use this class as a basis should either either use this handle directly to ensure that the data is flushed at obvious points in their implementation, or should call the save() method to ensure that it gets flushed.

data->

The contents of the data attribute are up to the user, but it must be a pointer to a hash, and the keys of that hash should be sensibly structured.

new - Create a new, unpopulated test session

$file = new DataFile(path, readWrite, timeout);

release - release the session

$file->release();

isLocked - check to see if we are Locked

Lock - explicitly lock when using MLDBM::Sync

Unlock - explicitly unlock when using MLDBM::Sync

path - get/set the path to the object

save - write out the object

$file->save();

cache - establish memory cache for items

$file->cache(size) ;

dirtyFlag - accessor for the flag indicating if data has changed..

$file->dirtyFlag();
$file->dirtyFlag(true|false);

useSync - accessor for useSync flag

_flock - get a lock on a file

$lock = $file->_flock($path, $readWrite, $timeout);