Remove finalize() for all Java classes (Bug #3846)
| Status: | Done | Start date: | 2014-08-06 |
|---|---|---|---|
| Priority: | Normal | Due date: | |
| Assignee: | Steven Goldsmith |
% Done: | 100% |
| Category: | java bindings | ||
| Target version: | 3.0 | ||
| Affected version: | 2.4.9 (latest release) | Operating System: | Linux |
| Difficulty: | Medium | HW Platform: | x64 |
| Pull request: |
Description
It is generally considered bad practice to use finalize since there no guraentee if or when it will be called. When you build applications that process a lot of images you will end up with a lot of finalizers in the queue and it eventually will get backed up. Another side effect as is demonstrated by Mat is that it will consume large amounts of memory since n_delete is never called (calling Mat.release() is a work around). Instead there should be some type of public clean up method that deallocates native memory and not rely on finalize().
References:
https://plumbr.eu/blog/debugging-to-understand-finalizer
http://stackoverflow.com/questions/158174/why-would-you-ever-implement-finalize
Associated revisions
Merge pull request #3846 from mshabunin:fix-headers
History
Updated by Steven Goldsmith over 10 years ago
This also affects 3.0.0 master branch.
Updated by Dmitry Retinskiy over 10 years ago
Steven,
if you could implement the correction it would be appreciated (see http://www.code.opencv.org/projects/opencv/wiki/How_to_contribute for details).
- Status changed from New to Open
- Assignee changed from Andrey Pavlenko to Steven Goldsmith
Updated by Steven Goldsmith almost 10 years ago
OK, sorry I didn't see this earlier. It's best to make gen_java.py generate proper clean up code. I'll see if I can get a submission in, thanks.
Updated by Steven Goldsmith almost 10 years ago
Added pull request: https://github.com/Itseez/opencv/pull/4006. Once that's accepted I'll fix the rest of the memory leaks and close this bug.
- Target version set to 3.0
Updated by Steven Goldsmith almost 10 years ago
Pull request merged into master.
- Status changed from Open to Done
- % Done changed from 0 to 100
Updated by Steven Goldsmith almost 10 years ago
https://github.com/Itseez/opencv/pull/4014 made delete() method public instead of protected, so calling code can access.