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How to free memory in Java?
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Java uses managed memory, so the only way you can allocate memory is by using the new operator, and the only way you can deallocate memory is by relying on the garbage collector.
This memory management whitepaper (PDF) may help explain what's going on.
You can also call Sy...
Generating random numbers in Objective-C
...te the S-Boxes via
arc4random_addrandom().
There is no need to call arc4random_stir() before using arc4random(), since arc4random() automatically
initializes itself.
EXAMPLES
The following produces a drop-in replacement for the traditional rand() and random() functions using
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Doing something before program exit
...t this works great for normal termination of the script, but it won't get called in all cases (e.g. fatal internal errors).
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How do I do base64 encoding on iOS?
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A really, really fast implementation which was ported (and modified/improved) from the PHP Core library into native Objective-C code is available in the QSStrings Class from the QSUtilities Library. I did a quick benchmark: a 5....
How do I protect Python code? [closed]
...ecutable is well-known, and the Python byte-codes are well understood.
Usually in cases like this, you have to make a tradeoff. How important is it really to protect the code? Are there real secrets in there (such as a key for symmetric encryption of bank transfers), or are you just being paranoi...
UILabel sizeToFit doesn't work with autolayout ios6
How am I supposed to configure programmatically (and in which method) a UILabel whose height depends on its text? I've been trying to set it up using a combination of Storyboard and code, but to no avail. Everyone recommends sizeToFit while setting lineBreakMode and numberOfLines . However, ...
window.close and self.close do not close the window in Chrome
...ec for window.close():
The close() method on Window objects should, if all the following conditions are met, close the browsing context A:
The corresponding browsing context A is script-closable.
The browsing context of the incumbent script is familiar with the browsing context A.
Th...
How to check for valid email address? [duplicate]
...ere is no point. Even if you can verify that the email address is syntactically valid, you'll still need to check that it was not mistyped, and that it actually goes to the person you think it does. The only way to do that is to send them an email and have them click a link to verify.
Therefore, a ...
Where does PostgreSQL store the database?
...here the data directory is, use this query.
show data_directory;
To see all the run-time parameters, use
show all;
You can create tablespaces to store database objects in other parts of the filesystem. To see tablespaces, which might not be in that data directory, use this query.
SELECT * FRO...
How to delete all the rows in a table using Eloquent?
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The reason MyModel::all()->delete() doesn't work is because all() actually fires off the query and returns a collection of Eloquent objects.
You can make use of the truncate method, this works for Laravel 4 and 5:
MyModel::truncate();
Th...