Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>So <code>Collection.unmodifiableList</code> is not REALLY thread-safe. This is because it create an unmodifiable view of the underlying <code>List</code>. However if the underlying <code>List</code> is modified while the view is being iterated you will get the CME. Remember that a CME does not need to be caused by a seperate thread. If I do the following I will get a CME:</p> <pre><code> for (String e : myList){ myList.remove(5); // throws CME } </code></pre> <p>The better choice is Guava's <a href="https://google.github.io/guava/releases/snapshot-jre/api/docs/com/google/common/collect/ImmutableList.html" rel="nofollow noreferrer">ImmutableList</a> which creates an immutable copy of the passed list.</p> <p>For clarification due to comments, replace the posted code with:</p> <pre><code> public List&lt;HierarchyNode&gt; getChildren() { return ImmutableList.copyOf(children); } </code></pre> <p>The <code>List</code> returned from this method is guarenteed to NEVER throw a CME.</p> <p>Update:</p> <p>If you are still trying to figure out why it is happining in your code, consider the following:</p> <ol> <li>Can the list of <code>children</code> EVER be modified (I am referring to the modifiable <code>List</code> that is passed to <code>unmodifiableList</code>)?</li> <li>Do any of the classes that call <code>getChildren</code> ever cause that class which holds the modifiable list to be invoked in a way that might update the list?</li> <li>Or do any of the classes get an instance of an <code>Iterator</code> that is used more than once?</li> </ol> <p><a href="https://google.github.io/guava/releases/snapshot-jre/api/docs/com/google/common/collect/ImmutableList.html" rel="nofollow noreferrer">ImmutableList</a></p>
    singulars
    1. This table or related slice is empty.
    1. POConcurrentModificationException in single Threaded unmodifiableList
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USJohn B
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COPlease elaborate your answer with example so that it can be understandable.
      singulars
      1. PO
      1. USBhavik Ambani
    2. COThread safety seems fairly unrelated here: *"I have a single threaded application"*.
      singulars
      1. PO
      1. USassylias
    3. CO+1 Another solution is to copy it. `return new ArrayList<HierarchyNode>(children); `
      singulars
      1. PO
      1. USPeter Lawrey
 

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