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When should one use a spinlock instead of mutex?
...
The Theory
In theory, when a thread tries to lock a mutex and it does not succeed, because the mutex is already locked, it will go to sleep, immediately allowing another thread to run. It will continue to sleep until being woken up, which will be the case ...
Invalidating JSON Web Tokens
...y be hit to record invalidations and remove expired invalidations and only read at server launch. Under a load-balancing architecture, the in-memory blacklist can poll the DB at short intervals, like 10s, limiting the exposure of invalidated tokens. These approaches allow the server to continue auth...
Releasing memory in Python
...ne or more free calls (for probably a bit more than 50.5mb)? You'd have to read your platform's malloc, and then walk the various tables and lists to see its current state. (On some platforms, it may even make use of system-level information, which is pretty much impossible to capture without making...
How do I detect whether a Python variable is a function?
...o be deprecated, but is now undeprecated, so you can use it again. You can read the discussion here: http://bugs.python.org/issue10518. You can do this with:
callable(obj)
If this is for Python 3.x but before 3.2, check if the object has a __call__ attribute. You can do this with:
hasattr(obj, '...
Understanding checked vs unchecked exceptions in Java
...ou can show a new File Dialog in this case.
4 . FileNotFoundException is already a checked exception.
5 . If it is expected that the method calling someMethod to catch the exception, the latter can be thrown. It just "passes the ball". An example of it usage would be if you want to throw it in your ...
commandButton/commandLink/ajax action/listener method not invoked or input value not set/updated
... the browser's JS console. Usually googling the exact error message will already give you the answer. See also Manually adding / loading jQuery with PrimeFaces results in Uncaught TypeErrors.
If you're using Ajax via JSF 2.x <f:ajax> or e.g. PrimeFaces <p:commandXxx>, make sure that you...
SQLite 数据库使用指导 · App Inventor 2 中文网
...材
setup.sql：可重复的建表与编号100示例。
readings.csv：编号101、102，两条真实CSV样本。
安卓与鸿蒙使用相同SQL、参数与素材；鸿蒙系统连接／关闭是异步过程，工程以真实状态和返回值判断。数据库、备份路径来...
Performant Entity Serialization: BSON vs MessagePack (vs JSON)
...tdout.write [1,2,3].to_msgpack
$stdout.write [1,2,3].to_msgpack
# read objects from stdin using streaming deserializer
unpacker = MessagePack::Unpacker.new($stdin)
# use iterator
unpacker.each {|obj|
p obj
}
...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...ng passed as keyword arguments to the dict constructor), it's difficult to read, it's not the intended usage, and so it is not Pythonic.
Here's an example of the usage being remediated in django.
Dictionaries are intended to take hashable keys (e.g. frozensets or tuples), but this method fails in Py...
How to have favicon / icon set when bookmarklet dragged to toolbar?
...
After reading the tapper[ware] and Restafarian site, here's the simplest solution I could come up with:
<a href="javascript:
var title = window.location.href;
if (title.indexOf('http://yourwebsite/bookmarklet/') == 0) {
'...