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How do I check if a file exists in Java?
...m there is an issue with stale file handles: bugs.java.com/bugdatabase/view_bug.do?bug_id=5003595 It's kind of obscure, but has been the cause of some frustrating bugs in production code before.
– CAW
Mar 17 '17 at 22:17
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git clone from another directory
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It's as easy as it looks.
14:27:05 ~$ mkdir gittests
14:27:11 ~$ cd gittests/
14:27:13 ~/gittests$ mkdir localrepo
14:27:20 ~/gittests$ cd localrepo/
14:27:21 ~/gittests/localrepo$ git init
Initialized empty Git repository in /home/andwed/gittests/localrepo...
Convert a string representation of a hex dump to a byte array using Java?
I am looking for a way to convert a long string (from a dump), that represents hex values into a byte array.
24 Answers
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Convert one date format into another in PHP
..., an invalid date that doesn't exactly match the format will return: Fatal error: Call to a member function format() on a non-object. Just a heads up!
– Rob W
Apr 11 '14 at 13:48
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How to install therubyracer gem on 10.10 Yosemite?
...t helps without any weirdness. Even though you may just be getting a libv8 error, do this! thanks.
– pjammer
Nov 2 '14 at 18:55
2
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What are the basic rules and idioms for operator overloading?
...ey.
The canonical form of providing these is this:
class X {
value_type& operator[](index_type idx);
const value_type& operator[](index_type idx) const;
// ...
};
Unless you do not want users of your class to be able to change data elements returned by operator[] (in which cas...
Is there a simple, elegant way to define singletons? [duplicate]
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class Foo:
def __init__(self):
print 'Foo created'
f = Foo() # Error, this isn't how you get the instance of a singleton
f = Foo.instance() # Good. Being explicit is in line with the Python Zen
g = Foo.instance() # Returns already created instance
print f is g # True
And here's the c...
Fill SVG path element with a background-image
Is it possible to set a background-image for an SVG <path> element?
1 Answer
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Creating the Singleton design pattern in PHP5
...nstance();
$fact == $fact2;
But:
$fact = new UserFactory()
Throws an error.
See http://php.net/manual/en/language.variables.scope.php#language.variables.scope.static to understand static variable scopes and why setting static $inst = null; works.
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How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
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Parsing ifconfig output is error-prone, for instance the above one-liner results in -bash: export: overruns:0': not a valid identifier` for me on RHEL6. Parsing /sys/class/net/$dev/statistics (see the perl script in @ephemient answer) directly works mu...