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Is there a Mutex in Java?
...ock;
import java.util.concurrent.locks.ReentrantLock;
private final Lock _mutex = new ReentrantLock(true);
_mutex.lock();
// your protected code here
_mutex.unlock();
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How to set a Django model field's default value to a function call / callable (e.g., a date relative
..., timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=datetime.now() + timedelta(days=1))
This last line is not defining a function; it is invoking a function to create a field in the class.
PRE Django 1.7
Django lets you pass a callable...
Spring Data JPA find by embedded object property
...Long twoId); and results in a query of the form: select ...... from one one_ left outer join two two_ on one_.two_id = two_.id where one_id = ? and two_.id = ?
– TroJaN
May 4 at 17:17
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How to get first element in a list of tuples?
...
do you mean something like this?
new_list = [ seq[0] for seq in yourlist ]
What you actually have is a list of tuple objects, not a list of sets (as your original question implied). If it is actually a list of sets, then there is no first element because set...
Object comparison in JavaScript [duplicate]
...
Unfortunately there is no perfect way, unless you use _proto_ recursively and access all non-enumerable properties, but this works in Firefox only.
So the best I can do is to guess usage scenarios.
1) Fast and limited.
Works when you have simple JSON-style objects without m...
Rails: fields_for with index?
...s there a method (or way to pull off similar functionality) to do a fields_for_with_index ?
9 Answers
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Refresh a page using JavaScript or HTML [duplicate]
...g (ajax) at loading. for example: www.yoursite.com/page/about?getVer=1&__[date]
Compare it to the stored versionnumber (stored in cookie or localStorage) if user has visited the page once, otherwise store it directly.
If version is not the same as local version, refresh the page using window.loc...
How do I move files in node.js?
...e rename function to do that.
http://nodejs.org/docs/latest/api/fs.html#fs_fs_rename_oldpath_newpath_callback
fs.rename(oldPath, newPath, callback)
Added in: v0.0.2
oldPath <String> | <Buffer>
newPath <String> | <Buffer>
callback <Function>
Asynchronous...
Passing a dictionary to a function as keyword parameters
...
This is great, just used it with argparse/__dict__ to make it really easy to do command line argument parsing directly into options for a class object.
– Horus
Jun 14 '12 at 3:47
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Efficiently convert rows to columns in sql server
... for ColumnName in (' + @cols + N')
) p '
exec sp_executesql @query;
See Demo.
Using an aggregate function
If you do not want to use the PIVOT function, then you can use an aggregate function with a CASE expression:
select
max(case when columnname = 'FirstName' then ...