I have a set of beans managed by spring. The scope of these beans is prototype ( a new instance is created each time they are obtained from the container). I created an aspect to advice setters on these beans to not proceed if the argument is null. Each time one of these beans is created (requested from the container) CGLIB generates a new proxy class for it and they don't get garbage collected. Eventually, I run out of permgen space. I appreciate your advice.