As of version 1.5 a new global caching function exists and the API own functionality will be removed in coming version.
class SetaPDF_Encryptor extends SetaPDF {
void setUseCache ( [boolean $usecache=false] ) }
(DEPRECATED) Is used to change the status of the caching function. Please note that the constant SetaPDF_ENCRYPTOR_CACHEPATH already needs to have been defined and contain a valid path to your file system, to which the Apache / PHP process can write and read. For more information on the caching function, please turn to the section on caching.
True or false – turns the API caching function on (true) or off (false).