jos-Error: Application Instantiation Error

JFactory :: getApplication() @ /htdocs/public/www/index.php:27
JApplication :: getInstance() @ /htdocs/public/www/libraries/joomla/factory.php:102
JSite -> __construct() @ /htdocs/public/www/libraries/joomla/application/application.php:180
JApplication -> __construct() @ /htdocs/public/www/includes/application.php:47
JApplication -> _createSession() @ /htdocs/public/www/libraries/joomla/application/application.php:145
JFactory :: getSession() @ /htdocs/public/www/libraries/joomla/application/application.php:1020
JFactory :: createSession() @ /htdocs/public/www/libraries/joomla/factory.php:152
JSession :: getInstance() @ /htdocs/public/www/libraries/joomla/factory.php:656
JSession -> __construct() @ /htdocs/public/www/libraries/joomla/session/session.php:151
JSession -> _start() @ /htdocs/public/www/libraries/joomla/session/session.php:114
session_start() @ /htdocs/public/www/libraries/joomla/session/session.php:537
JSessionStorageDatabase -> read()
JDatabase -> loadResult() @ /htdocs/public/www/libraries/joomla/session/storage/database.php:50
JDatabaseMySQL -> execute() @ /htdocs/public/www/libraries/joomla/database/database.php:1164
JError :: raiseError() @ /htdocs/public/www/libraries/joomla/database/database/mysql.php:548
JError :: raise() @ /htdocs/public/www/libraries/joomla/error/error.php:251
JError :: throwError() @ /htdocs/public/www/libraries/joomla/error/error.php:176
call_user_func_array() @ /htdocs/public/www/libraries/joomla/error/error.php:214
JError :: handleCallback()
call_user_func() @ /htdocs/public/www/libraries/joomla/error/error.php:765
JError :: customErrorPage()
JFactory :: getApplication() @ /htdocs/public/www/libraries/joomla/error/error.php:784
JError :: raiseError() @ /htdocs/public/www/libraries/joomla/factory.php:99
JError :: raise() @ /htdocs/public/www/libraries/joomla/error/error.php:251