The problem is that the pool becomes too big and wastes memory It is fine when the user keeps opening files and the parser can reuse the objects. But eventua

The problem is that the pool becomes too big and wastes memory It is fine when the user keeps opening files and the parser can reuse the objects. But eventually, the user has opened all the files he needs. Then the process will never open another file again, and none of the objects can be reused. But they also cannot be freed, when some objects are still used, e.g. when the user did not close all files.