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How to create a directory in Java?

... -1: That is actually a really bad technique to create a directory. The access to the FS is not reserved to a dedicated resource. Between if(!theDir.exists()) and theDir.mkdir() the status could have changed, as well as it could change in bet...
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What is the difference between a weak reference and an unowned reference?

...a.k.a. they don't increase the retain count in order to prevent ARC from deallocating the referred object). But why two keywords? This distinction has to do with the fact that Optional types are built-in the Swift language. Long story short about them: optional types offer memory safety (this works ...
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How to calculate the running time of my program? [duplicate]

... This is outdated. Better answers all across SO - this should be deleted. Especially since it doesn't discourage manual calculation of unit conversions. – anon58192932 Jan 26 '18 at 22:54 ...
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What is the better API to Reading Excel sheets in java - JXL or Apache POI [closed]

...ry) ".xls" format. Apache POI supports both with a common design. Additionally, the Java portion of the JXL API was last updated in 2009 (3 years, 4 months ago as I write this), although it looks like there is a C# API. Apache POI is actively maintained. JXL doesn't support Conditional Formatting,...
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How can I compare two dates in PHP?

... If all your dates are posterior to the 1st of January of 1970, you could use something like: $today = date("Y-m-d"); $expire = $row->expireDate; //from database $today_time = strtotime($today); $expire_time = strtotime($exp...
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How to create a hash or dictionary object in JavaScript [duplicate]

...sed instead of simply using Object. It is supported by current versions of all major browsers. Maps do not support the [subscript] notation used by Objects. That syntax implicitly casts the subscript value to a primitive string or symbol. Maps support any values as keys, so you must use the methods...
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Python pip install fails: invalid command egg_info

I find that recently often when I try to install a Python package using pip , I get the error(s) below. 15 Answers ...
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Currency formatting in Python

...ting. >>> import locale >>> locale.setlocale( locale.LC_ALL, '' ) 'English_United States.1252' >>> locale.currency( 188518982.18 ) '$188518982.18' >>> locale.currency( 188518982.18, grouping=True ) '$188,518,982.18' ...
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How can I avoid Java code in JSP files, using JSP 2?

...ance/composition. Debuggability: if scriptlet throws an exception halfway, all you get is a blank page. Testability: scriptlets are not unit-testable. Maintainability: per saldo more time is needed to maintain mingled/cluttered/duplicated code logic. Sun Oracle itself also recommends in the JSP co...
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jQuery: Best practice to populate drop down?

The example I see posted all of the time seems like it's suboptimal, because it involves concatenating strings, which seems so not jQuery. It usually looks like this: ...