JavaBlock — release any Java objects created during evaluation once evaluation finishes
BeginJavaBlock,
EndJavaBlock — mark the beginning and end of a Java block
KeepJavaObject — allow a Java object to persist when the current
JavaBlock ends
ReleaseJavaObject — finish using a Java object in
Mathematica
SameObjectQ — whether two
JavaObject expressions reference the same Java object
LoadedJavaObjects,
LoadedJavaClasses — list all Java objects or classes in use
