025: Effective Java for Android developers : Item 7

In this mini Fragment, we introduce Joshua’s seventh Item and a momentous end to the first chapter: Avoid finalizers

Stay tuned for more items from our “Effective Java for Android developers” Fragment series.

Download

Show Notes

Avoid finalizers

  • If you don’t know what they are, ignorance is bliss. If you know what they are, avoid them!
  • Finalizers in Java != destructors in C++ (C++ counterparts to constructors).
  • In C++ destructors
    • you reclaim resources here (Java has GC)
    • you also reclaim non-memory resources (use the try-finally block in Java)
  • (unpredicatable amt of time between object becoming unreachable and finalizer being executed) Never do anything time critical in finalizer!
    • System.gc + System.runFinalization increase chances – no guarantee
    • System.runFinalizersOnExit + Runtime.runFinalizersOnExit are the ones that do – but they are fatally flawed
  • Java 7 has try with resources, which is also interesting and auto-closeables. [Android] devs can only dream of these.
  • If an uncaught exception is thrown in a finalizer, it is ignored, and the finalization abruptly terminates.
  • Severe performance penalty for using finalizers – (one e.g.) time to create and destroy simple object goes from 5.6ns -> 2400ns
  • Only valid use: as a safety net or to terminate noncritical native resources.
  • [Android] you’re probably better off using Android’s lifecycle methods.

Contact

024: Effective Java for Android developers : Item 6

Joshua’s sixth Item: Eliminate obsolete object references, in a distinctively croaky voice.

Stay tuned for more items from our “Effective Java for Android developers” Fragment series.

Download

Show Notes

Eliminate obsolete object references

Supplemental reading (for the diligent ones that follow shownotes)

Contact

023: Android Dev Summit Recap

Donn and Kaushik cover the happenings of Google’s very first Android Developer conference – “Android Dev Summit”. Together, they attended the conference both virtually and physically! Listen on for the highlights.

Download

Sessions

Sample projects

Contact us:

022: Effective Java for Android developers : Item 5

In this mini Fragment, we introduce Joshua’s fifth Item: Avoid creating unnecessary objects.

Stay tuned for more items from our “Effective Java for Android developers” Fragment series.

Download

Show Notes

Avoid creating unnecessary objects

Snippet to demonstrate AutoBoxing problems

// sum of all positive values
Long sum = 0L;
for (long i=0; i< Integer.MAX_VALUE; i++) {
  sum+=i;
}

Contact

021: Diving Deep with Dagger

Download

Show Notes

In other news

Dagger

Jesse Wilson Cameo

Other references

Awesome picks:

Donn’s picks:

KG’s picks:

Contact us: