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How to synchronize a static variable among threads running different instances of a class in Java?
...nized static method. This synchronizes on the class object.
public class Test {
private static int count = 0;
public static synchronized void incrementCount() {
count++;
}
}
Explicitly synchronize on the class object.
public class Test {
private static int count = 0;
...
the item you requested is not available for purchase
...K on your device not launch the app in the debugger.
Make sure to create a test account in your developer console.
Setup you testing account
Make sure to sign in your device with your test account.
In a case of closed alpha/beta testing, make sure you have added your test account to selected teste...
Python Sets vs Lists
...as lists, except for their immutability.
Iterating
>>> def iter_test(iterable):
... for i in iterable:
... pass
...
>>> from timeit import timeit
>>> timeit(
... "iter_test(iterable)",
... setup="from __main__ import iter_test; iterable = set(range(10...
What is the difference between “def” and “val” to define a function
...n
//Boolean = true
With def you can get new function on every call:
val test: () => Int = {
val r = util.Random.nextInt
() => r
}
test()
// Int = -1049057402
test()
// Int = -1049057402 - same result
def test: () => Int = {
val r = util.Random.nextInt
() => r
}
test()
// In...
Java String - See if a string contains only numbers and not letters
...ther solutions, because at least require exception handling.
I've run jmh tests and have found that iterating over String using charAt and comparing chars with boundary chars is the fastest way to test if string contains only digits.
JMH testing
Tests compare performance of Character.isDigit vs P...
Design patterns or best practices for shell scripts [closed]
...ts=`getopt -s bash -o c:d:: --long config_file:,debug_level:: -- "$@"`
if test $? != 0
then
echo "unrecognized option"
exit 1
fi
eval set -- "$getopt_results"
while true
do
case "$1" in
--config_file)
CommandLineOptions__config_file="$2";
shift 2;
...
Accept function as parameter in PHP
...
PHP VERSION >= 5.3.0
Example 1: basic
function test($test_param, $my_function) {
return $my_function($test_param);
}
test("param", function($param) {
echo $param;
}); //will echo "param"
Example 2: std object
$obj = new stdClass();
$obj->test = function ($t...
How do I search for an object by its ObjectId in the mongo console?
...e matters) and that the ObjectId is exact.
Documentation is here
> db.test.insert({x: 1})
> db.test.find() // no criteria
{ "_id" : ObjectId("4ecc05e55dd98a436ddcc47c"), "x" : 1 }
> db.test.find({"_id" : ObjectId("4ecc05e55dd98a436ddcc...
Is the != check thread safe?
...
In the absence of synchronization this code
Object a;
public boolean test() {
return a != a;
}
may produce true. This is the bytecode for test()
ALOAD 0
GETFIELD test/Test1.a : Ljava/lang/Object;
ALOAD 0
GETFIELD test/Test1.a : Ljava/lang/Object;
IF_ACMPEQ L1
...
a...
How to profile a bash shell script slow startup?
...d
Reading this and because profiling is an important step, I've done some test and research about this whole SO question and already posted answers.
There is 4+ answer:
The first is based on @DennisWilliamson's idea but with a lot less of resource consumption
The second was my own (before this;)...