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What is an efficient way to implement a singleton pattern in Java? [closed]
...pt that it is more concise, provides the serialization machinery for free, and provides an ironclad guarantee against multiple instantiation, even in the face of sophisticated serialization or reflection attacks. While this approach has yet to be widely adopted, a single-element enum type is the bes...
Volatile Vs Atomic [duplicate]
...rite -- such as i++, which is equivalent to i = i + 1, which does one read and one write -- is not atomic, since another thread may write to i between the read and the write.
The Atomic classes, like AtomicInteger and AtomicReference, provide a wider variety of operations atomically, specifically i...
How to copy a selection to the OS X clipboard
...this might not work for you, but if you have Vim-version 7.4 then it does (and sometimes you don't even have to do the whole "+y ). And you check this by just writing >vim in the terminal and then the version-number is when you start it up.
– Zeth
Sep 9 '1...
How to change the name of a Django app?
... have changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver
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When should one use a 'www' subdomain?
When browsing through the internet for the last few years, I'm seeing more and more pages getting rid of the 'www' subdomain.
...
Conditional formatting based on another cell's value
...low, it actually means "B{current_row}", so for C5 it's B5, for C6 it's B6 and so on. Unless you specify $B$5 - then you refer to one specific cell.
This is supported in Google Sheets as of 2015:
https://support.google.com/drive/answer/78413#formulas
In your case, you will need to set conditiona...
How to create a file in memory for user to download, but not through server?
Is there any way I can create a text file on the client side and prompt the user to download it, without any interaction with the server?
I know I can't write directly to their machine (security and all), but can I create and prompt them to save it?
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How many database indexes is too many?
...nds on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since they all ...
How to convert TimeStamp to Date in Java?
... @vs06 What makes you think it is deprecated? The latest java 7 and 8 docs both say otherwise (docs.oracle.com/javase/7/docs/api/java/util/Date.html#getTime() and docs.oracle.com/javase/8/docs/api/java/util/Date.html#getTime--)
– Alex Coleman
Sep 22 ...
iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]
..., then definitely consider using Auto Layout. It removes all fixed layout handling and instead uses constraints to lay things out. Nothing will be hard-coded, and your life will become a lot simpler.
However, if you have to support older iOS's, then it really depends on your application. A majority...