大约有 48,000 项符合查询结果（耗时：0.0567秒） [XML]
What is a semaphore?
...ere are a dedicated number of people that are allowed in the club at once. If the club is full no one is allowed to enter, but as soon as one person leaves another person might enter.
It's simply a way to limit the number of consumers for a specific resource. For example, to limit the number of sim...
Fragment lifecycle - which method is called upon show / hide?
...
Similar to activity lifecycle, Android calls onStart() when fragment becomes visible. onStop() is normally called when fragment becomes invisible, but it can also be called later in time.
Depending on your layout Android can call onStart() even,...
How to write multiple line property value using PropertiesConfiguration?
...
If you mean the following; that just relies on backslash + end-of-line. I just found it documented in:
http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html
primes = 2,\
3,\
5,\
7,\
11
...
How do you clear a stringstream variable?
...nherited from ios and is used to clear the error state of the stream, e.g. if a file stream has the error state set to eofbit (end-of-file), then calling clear() will set the error state back to goodbit (no error).
For clearing the contents of a stringstream, using:
m.str("");
is correct, althou...
The Ruby %r{ } expression
...
If you use spaces as your delimiter, your regular expression will break if you add spaces to it later. I think the idea is to use delimiters that don't match anything in your regular expression, with curly braces as the prefe...
What really happens in a try { return x; } finally { x = null; } statement?
I saw this tip in another question and was wondering if someone could explain to me how on earth this works?
5 Answers
...
How does python numpy.where() work?
..., True, True]], dtype=bool)
This is the same reason why something like if x > 5: raises a ValueError if x is a numpy array. It's an array of True/False values, not a single value.
Furthermore, numpy arrays can be indexed by boolean arrays. E.g. x[x>5] yields [6 7 8], in this case.
Hones...
Rails: where does the infamous “current_user” come from?
...his only come from Devise? and do I have to manually define it myself even if I use Devise? Are there prerequisites to using current_user (like the existence of sessions, users, etc)?
...
What's the difference between @Secured and @PreAuthorize in spring security 3?
It's not clear for me what is the difference in spring security between :
5 Answers
5...
Regular expression to find URLs within a string
... string? I've found a lot of regular expressions on Google for determining if an entire string is a URL but I need to be able to search an entire string for URLs. For example, I would like to be able to find www.google.com and http://yahoo.com in the following string:
...