Databases
StackOverflow2013
Postsdbo
POControlling race condition at startup
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POControlling race condition at startup
    primarykey
    data
    text
    <p>I have some code that I want to have some one time initialisation performed. But this code doesn't have a definite lifecycle, so my logic can be potentially invoked by multiple threads before my initialisation is done. So, I want to basically ensure that my logic code "waits" until initialisation is done.</p> <p>This is my first cut.</p> <pre><code>public class MyClass { private static final AtomicBoolean initialised = new AtomicBoolean(false); public void initialise() { synchronized(initialised) { initStuff(); initialised.getAndSet(true); initialised.notifyAll(); } } public void doStuff() { synchronized(initialised) { if (!initialised.get()) { try { initialised.wait(); } catch (InterruptedException ex) { throw new RuntimeException("Uh oh!", ex); } } } doOtherStuff(); } } </code></pre> <p>I basically want to make sure this is going to do what I think it's going to do -- block doStuff until the initialised is true, and that I'm not missing a race condition where doStuff might get stuck on a Object.wait() that will never arrive.</p> <p>Edit:</p> <p>I have no control over the threads. And I want to be able to control when all of the initialisation is done, which is why doStuff() can't call initialise().</p> <p>I used an AtomicBoolean as it was a combination of a value holder, and an object I could synchronize. I could have also simply had a "public static final Object lock = new Object();" and a simple boolean flag. AtomicBoolean conveniently gave me both. A Boolean can not be modified.</p> <p>The CountDownLatch is exactly what I was looking for. I also considered using a Sempahore with 0 permits. But the CountDownLatch is perfect for just this task.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USWill Hartung
    1. USWill Hartung
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POControlling race condition at startup
      1. USRicardo Marimon
      1. VTFavorite
    2. VO
      singulars
      1. POControlling race condition at startup
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POControlling race condition at startup
      1. USMichael Chinen
      1. VTFavorite
    1. COWhy not use a static initializer?
      singulars
      1. POControlling race condition at startup
      1. USNG.
    2. COwhere does initialize get called?
      singulars
      1. POControlling race condition at startup
      1. USluke
    3. CODo you launch a thread in your constructor to do the initialization work or not?
      singulars
      1. POControlling race condition at startup
      1. USRicardo Marimon
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload