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How do I check if a file exists in Java?

... edited Sep 7 '18 at 12:40 DVK 117k2828 gold badges194194 silver badges306306 bronze badges answered Nov 29 '09 at 20:35 ...
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What is the size of ActionBar in pixels?

I need to know the exact size of ActionBar in pixels so to apply correct background image. 13 Answers ...
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Difference between IsNullOrEmpty and IsNullOrWhiteSpace in C# [duplicate]

... shA.t 14.6k55 gold badges4646 silver badges8989 bronze badges answered Sep 10 '13 at 4:21 fionbiofionbio ...
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Design by contract using assertions or exceptions? [closed]

When programming by contract a function or method first checks whether its preconditions are fulfilled, before starting to work on its responsibilities, right? The two most prominent ways to do these checks are by assert and by exception . ...
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Why is using the JavaScript eval function a bad idea?

... Improper use of eval opens up your code for injection attacks Debugging can be more challenging (no line numbers, etc.) eval'd code executes slower (no opportunity to compile/cache eval'd code) Edit: As @Jeff Walden points out in comments, #3 is less true today than it was in 2008....
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Is there any difference between “foo is None” and “foo == None”?

... BrendanBrendan 16.6k1414 gold badges7474 silver badges100100 bronze badges ...
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convert a list of objects from one type to another using lambda expression

... JaredParJaredPar 648k133133 gold badges11601160 silver badges13951395 bronze badges ...
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Java array reflection: isArray vs. instanceof

...you test an object's type before downcasting to a particular type which is known at compile time. For example, perhaps you wrote some code that can work with a Integer[] or an int[]. You'd want to guard your casts with instanceof: if (obj instanceof Integer[]) { Integer[] array = (Integer[]) ob...
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How to get pixel data from a UIImage (Cocoa Touch) or CGImage (Core Graphics)?

...coa Touch). From that, I'm happy to get a CGImage or anything else you'd like that's available. I'd like to write this function: ...
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Keeping ASP.NET Session Open / Alive

Which is the easiest and most unobstrusive way to keep an ASP.NET session alive as long as the user has the browser window open? Is it timed AJAX calls? I want to prevent the following: sometimes users keep their window open for a long time, then enter stuff, and on submit nothing works anymore beca...