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How to start two threads at “exactly” the same time
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// Now if we block on the gate from the main thread, it will open
// and all threads will start to do stuff!
gate.await();
System.out.println("all threads started");
This doesn't have to be a CyclicBarrier, you could also use a CountDownLatch or even a lock.
This still can't make sure that ...
Using current time in UTC as default value in PostgreSQL
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I can see a funciton like now_utc() really shines when writing queries
– misaxi
Nov 1 '15 at 7:04
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Which iomanip manipulators are 'sticky'?
... the comments below:
By Martin:
@Chareles: Then by this requirement all manipulators are sticky. Except setw which seems to be reset after use.
By Charles:
Exactly! and the only reason that setw appears to behave differently is because there are requirements on formatted output operat...
Difference between val() and text()
...ut element -- regardless of type. .text() gets the innerText (not HTML) of all the matched elements:
.text()
The result is a string that contains
the combined text contents of all
matched elements. This method works on
both HTML and XML documents. Cannot be
used on input elements. For i...
How to print a int64_t type in C
... hexadecimal.
cppreference.com has a full listing of available macros for all types including intptr_t (PRIxPTR). There are separate macros for scanf, like SCNd64.
A typical definition of PRIu16 would be "hu", so implicit string-constant concatenation happens at compile time.
For your code to ...
Why covariance and contravariance do not support value type
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Basically, variance applies when the CLR can ensure that it doesn't need to make any representational change to the values. References all look the same - so you can use an IEnumerable<string> as an IEnumerable<object>...
Closing JDBC Connections in Pool
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Yes, certainly you need to close the pooled connection as well. It's actually a wrapper around the actual connection. It wil under the covers release the actual connection back to the pool. It's further up to the pool to decide whether the actual connection will actually be closed or be reused for...
When to add what indexes in a table in Rails
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Should I add "index" to all the foreign keys like "xxx_id"?
It would be better, because it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be created aut...
Can you make just part of a regex case-insensitive?
...ase-insensitive by using the (?i:) pattern modifier.
Modern regex flavors allow you to apply modifiers to only part of the regular expression. If you insert the modifier (?ism) in the middle of the regex, the modifier only applies to the part of the regex to the right of the modifier. You can turn ...
get current url in twig template?
...ttributes.get('_route_params')) %}
The app global view variable contains all sorts of useful shortcuts, such as app.session and app.security.token.user, that reference the services you might use in a controller.
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