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Why does Java switch on contiguous ints appear to run faster with added cases?
...value has been removed in JDK 8 after more benchmarking was performed.
Finally, when the method becomes too long (> 25 cases in my tests), it is in not inlined any longer with the default JVM settings - that is the likeliest cause for the drop in performance at that point.
With 5 cases, the d...
Delete an element from a dictionary
... use an an already constructed dict without a single item as **kwargs, some_function(**{k:v for k,v in some_dict.items() if k not 'some_key'})
– Cole
Nov 19 '17 at 21:14
...
How can I start PostgreSQL server on Mac OS X?
...
The Homebrew package manager includes launchctl plists to start automatically. For more information, run brew info postgres.
Start manually
pg_ctl -D /usr/local/var/postgres start
Stop manually
pg_ctl -D /usr/local/var/postgres stop
Start automatically
"To have launchd start postgresql now and res...
When is TCP option SO_LINGER (0) required?
...void large numbers of connections sitting in the TIME_WAIT state, tying up all the available resources on a server.
When a TCP connection is closed cleanly, the end that initiated the close ("active close") ends up with the connection sitting in TIME_WAIT for several minutes. So if your protocol i...
Understand the “Decorator Pattern” with a real world example
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Decorator pattern achieves a single objective of dynamically adding
responsibilities to any object.
Consider a case of a pizza shop. In the pizza shop they will sell few pizza varieties and they will also provide toppings in the menu. Now imagine a situation wherein if the piz...
Error: Could not create the Java Virtual Machine Mac OSX Mavericks
I just installed the latest Java SDK 7-67 from Oracle on the Mac 10.9.4. I then ran the command java -v in Terminal and I get this message:
...
How to remove item from array by value? [duplicate]
...is can be a global function or a method of a custom object, if you aren't allowed to add to native prototypes. It removes all of the items from the array that match any of the arguments.
Array.prototype.remove = function() {
var what, a = arguments, L = a.length, ax;
while (L && th...
How to perform Callbacks in Objective-C
...newer) option is to use blocks:
@interface MyClass: NSObject
{
void (^_completionHandler)(int someParameter);
}
- (void) doSomethingWithCompletionHandler:(void(^)(int))handler;
@end
@implementation MyClass
- (void) doSomethingWithCompletionHandler:(void(^)(int))handler
{
// NOTE: copyin...
How do I read from parameters.yml in a controller in symfony2?
...and then - the needed parameter.
$this->container->getParameter('api_user');
This documentation chapter explains it.
While $this->get() method in a controller will load a service (doc)
In Symfony 2.7 and newer versions, to get a parameter in a controller you can use the following:
$th...
Registry Key '…' has value '1.7', but '1.6' is required. Java 1.7 is Installed and the Registry is P
... one of the server admins "updated" our Java to an older version and uninstalled the one we were using. Don't ask me why, I don't know. I re-installed Java 1.7 and uninstalled 1.6 along with the JREs.
...