I just read about this topic in The Well-Grounded Rubyist (great book, by the way). The author does a better job of explaining than I would so I’ll quote him: No single rule or formula always results in the right design. But it’s useful to keep a couple of considerations in mind when you’re making … Read more
Private constructor and static methods on a class marked as final.
jd-gui is the best decompiler at the moment. it can handle newer features in Java, as compared to the getting-dusty JAD.
SomeClass::class will return the fully qualified name of SomeClass including the namespace. This feature was implemented in PHP 5.5. Documentation: http://php.net/manual/en/migration55.new-features.php#migration55.new-features.class-name It’s very useful for 2 reasons. You don’t have to store your class names in strings anymore. So, many IDEs can retrieve these class names when you refactor your code You can use the … Read more
Intro: Nested classes relate to other classes a little differently than outer classes. Taking Java as an example: Non-static nested classes have access to other members of the enclosing class, even if they are declared private. Also, non-static nested classes require an instance of the parent class to be instantiated. OuterClass outerObj = new OuterClass(arguments); … Read more
The reason that the performance of instanceof and getClass() == … is different is that they are doing different things. instanceof tests whether the object reference on the left-hand side (LHS) is an instance of the type on the right-hand side (RHS) or some subtype. getClass() == … tests whether the types are identical. So … Read more
All functions are also descriptors, so you can bind them by calling their __get__ method: bound_handler = handler.__get__(self, MyWidget) Here’s R. Hettinger’s excellent guide to descriptors. As a self-contained example pulled from Keith’s comment: def bind(instance, func, as_name=None): “”” Bind the function *func* to *instance*, with either provided name *as_name* or the existing name of … Read more
If you have only one instance anyway, it’s best to make all variables per-instance, simply because they will be accessed (a little bit) faster (one less level of “lookup” due to the “inheritance” from class to instance), and there are no downsides to weigh against this small advantage.
By what you wrote, you are missing a critical piece of understanding: the difference between a class and an object. __init__ doesn’t initialize a class, it initializes an instance of a class or an object. Each dog has colour, but dogs as a class don’t. Each dog has four or fewer feet, but the class … Read more
This selects the second LI element. document.querySelector(“li:not([class])”) or document.querySelector(“li:not(.completed):not(.selected)”) Example: // select li which doesn’t have a ‘class’ attribute… console.log(document.querySelector(“li:not([class])”)) // select li which doesn’t have a ‘.completed’ and a ‘.selected’ class… console.log(document.querySelector(“li:not(.completed):not(.selected)”)) <ul id=”tasks”> <li class=”completed selected”>One Task</li> <li>Two Task</li> </ul>