The Java EE 5 Tutorial

Releasing Resources

It’s recommended practice that all tag handlers implement a release method, which releases resources allocated during the execution of the tag handler. The release method of MapTag as follows:

public void release() {
    current = null;
    styleClass = null;
    actionListener = null;
    immediate = null;
    action = null;

This method first calls the UIComponentTag.release method to release resources associated with UIComponentTag. Next, the method sets all attribute values to null.