117  * the object reference, by referring to fields of the object being cleaned,

   117  * the object reference, by referring to fields of the object being cleaned,

   118  * preventing the object from becoming phantom reachable.

   118  * preventing the object from becoming phantom reachable.

   119  * Using a static nested class, as above, will avoid accidentally retaining the

   119  * Using a static nested class, as above, will avoid accidentally retaining the

   120  * object reference.

   120  * object reference.

   121  * <p>

   121  * <p>

   123  * Cleaning actions should be prepared to be invoked concurrently with

   123  * Cleaning actions should be prepared to be invoked concurrently with

   124  * other cleaning actions.

   124  * other cleaning actions.

   125  * Typically the cleaning actions should be very quick to execute

   125  * Typically the cleaning actions should be very quick to execute

   126  * and not block. If the cleaning action blocks, it may delay processing

   126  * and not block. If the cleaning action blocks, it may delay processing

   127  * other cleaning actions registered to the same cleaner.

   127  * other cleaning actions registered to the same cleaner.