Since JOAFIP make able to manage more objects than memory can
contains, it is important that all objects read or wrote are deleted
from memory when data access session is closed.
To check if
achieving the goal a tool has been add to detect memory leak. This
the role of MemInspector class to create list of object in memory (
weak references ) and make able to see added object from an object
list to another. All object in memory have a reference path from the
root object.
download
memory inspector jar
download
memory inspector source
Example of
checking file persistence
memory link:
/*
get the memory inspector service instance */
final MemInspector memInspector =
MemInspector.getInstance();
/*
Only interested by creation of object from joafip package class */
memInspector.setMainPackageName("net.sf.joafip");
bob1.setBob2(new Bob2());
/*
* After doing initialization and some object storing, get the object
in
* memory
in initial
object map.
*/
memInspector.inspect(this,
false/* markNew
*/);
/* add an
object */
bob1.setBob3(new Bob3());
/*
* Get the object in memory and log those added to initially in
memory
*/
memInspector.inspect(this,
true/* markNew
*/);
/*
* is there object added
*/
System.out.println("added
object :"+memInspector.added());//NOPMD
/*
* output
in text
file
*/
final PrintStream stream = new PrintStream(new
File("runtime/mem.txt"));
memInspector.log(stream);
stream.close();
/*
* output for ShowObjectTree
*/
memInspector.xstreamTree(new File("runtime/mem.xml"));
Below the log obtained, this is
the objects that stay in memory after a data access session usage. A
path to object staying in memory to root object is also log for debug
purpose.
*
class net.sf.joafip.meminspector.MainTestMemInspector 20181463
* class net.sf.joafip.store.service.objectfortest.Bob1 9042915
= class net.sf.joafip.store.service.objectfortest.Bob2 32425490
+ class net.sf.joafip.store.service.objectfortest.Bob3 6794265
Or using
net.sf.joafip.meminspector.service.ShowObjectTree
