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How to check if a service is running on Android?
How do I check if a background service is running?
31 Answers
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Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
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Why does this Java code compile?
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tl;dr
For fields, int b = b + 1 is illegal because b is an illegal forward reference to b. You can actually fix this by writing int b = this.b + 1, which compiles without complaints.
For local variables, int d = d + 1 is illegal because d is not initialize...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
...nHelper onCreate() and onUpgrade() callbacks are invoked when the database is actually opened, for example by a call to getWritableDatabase(). The database is not opened when the database helper object itself is created.
SQLiteOpenHelper versions the database files. The version number is the int ar...
How does LMAX's disruptor pattern work?
I am trying to understand the disruptor pattern . I have watched the InfoQ video and tried to read their paper. I understand there is a ring buffer involved, that it is initialized as an extremely large array to take advantage of cache locality, eliminate allocation of new memory.
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When to use self over $this?
In PHP 5, what is the difference between using self and $this ?
23 Answers
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What is the difference between “def” and “val” to define a function
What is the difference between:
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Referring to the null object in Python
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In Python, the 'null' object is the singleton None.
The best way to check things for "Noneness" is to use the identity operator, is:
if foo is None:
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How to choose an AES encryption mode (CBC ECB CTR OCB CFB)?
...k of data with the same key.
CBC, OFB and CFB are similar, however OFB/CFB is better because you only need encryption and not decryption, which can save code space.
CTR is used if you want good parallelization (ie. speed), instead of CBC/OFB/CFB.
XTS mode is the most common if you are encoding a ran...
Check whether a path is valid in Python without creating a file at the path's target
...ath (including directory and file name).
I need to test if the file-name is a valid, e.g. if the file-system will allow me to create a file with such a name.
The file-name has some unicode characters in it.
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