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Is there an eval() function in Java? [duplicate]
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You can use the ScriptEngine class and evaluate it as a Javascript string.
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
Object result = engine.eval("4*5");
There may be a better way, but this ...
Android: How to stretch an image to the screen width while maintaining aspect ratio?
...to download an image (of unknown size, but which is always roughly square) and display it so that it fills the screen horizontally, and stretches vertically to maintain the aspect ratio of the image, on any screen size. Here is my (non-working) code. It stretches the image horizontally, but not vert...
Technically what is the main difference between Oracle JDK and OpenJDK? [duplicate]
...ms. But since I started to play with it for big toys, I started to notice random/unknown fatal error and crashes (with H.264 codecs, etc.), and it was a nightmare till then to get ride of system crash+fatal errors caused by OpenJDK.
...
How to check for an undefined or null variable in JavaScript?
...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || de...
Python circular importing?
... specific to your case: Try changing entities/post.py to do import physics and then refer to physics.PostBody rather than just PostBody directly. Similarly, change physics.py to do import entities.post and then use entities.post.Post rather than just Post.
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Windows threading: _beginthread vs _beginthreadex vs CreateThread C++
...ulate that MS originally intended the _begin routines to be internal calls and CreateThread was supposed to be the API function everyone would call. Another potential explanation is that MS has a long & glorious history of ignoring the standard & making very bad decisions about naming thing...
Constructors vs Factory Methods [closed]
...ns: Elements of Reusable Object-Oriented Software by Gamma, Helm, Johnson, and Vlissides.
Use the Factory Method pattern when
a class can't anticipate the class of objects it must create
a class wants its subclasses to specify the objects it creates
classes delegate responsibility to one of sever...
What does the “at” (@) symbol do in Python?
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An @ symbol at the beginning of a line is used for class, function and method decorators.
Read more here:
PEP 318: Decorators
Python Decorators
The most common Python decorators you'll run into are:
@property
@classmethod
@staticmethod
If you see an @ in the middle of a line, that's ...
ARC and bridged cast
...ained <CFType>) op or alternatively CFBridgingRetain(op) is used to hand an NSObject over to CF-land while giving it a +1 retain count. You should handle a CFTypeRef you create this way the same as you would handle a result of CFStringCreateCopy(). This could also be represented by CFRetain((_...
NUnit vs. Visual Studio 2008's test projects for unit testing [closed]
I am going to be starting up a new project at work and want to get into unit testing. We will be using Visual Studio 2008, C#, and the ASP.NET MVC stuff. I am looking at using either NUnit or the built-in test projects that Visual Studio 2008 has, but I am open to researching other suggestions. ...