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Variables are SHADOWED and methods are OVERRIDDEN. Which variable will be used depends on the class that the variable is declared of. Which method will be used depends on the actual class of the object that is referenced by the variable. class Car { public int gearRatio = 8; public St...

Casting an instance of a base class to a subclass as in : b = (B) a; is called narrowing (as you are trying to narrow the base class object to a more specific class object) and needs an explicit type-cast. Casting an instance of a subclass to a base class as in: A a = b; is called widening and does...

If we try to change an object on the UI thread from a different thread we will get a cross-thread operation exception: Private Sub Button_Click(sender As Object, e As EventArgs) Handles MyButton.Click ' Cross thread-operation exception as the assignment is executed on a different thread '...

Random and ThreadLocalRandom are good enough for everyday use, but they have a big problem: They are based on a linear congruential generator, an algorithm whose output can be predicted rather easily. Thus, these two classes are not suitable for cryptographic uses (such as key generation). One can ...

Drag 1 textbox and 1 button Double click the button1 and you will be transferred to the Button1_Click event Public Class Form1 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click End Sub End Class Type the name of the object that you want to target, ...

Using sw As New System.IO.StreamWriter("path\to\file.txt") sw.WriteLine("Hello world") End Using The use of a Using block is recommended good practice when using an object that Implements IDisposable

std::ifstream f("file.txt"); if (f) { std::stringstream buffer; buffer << f.rdbuf(); f.close(); // The content of "file.txt" is available in the string `buffer.str()` } The rdbuf() method returns a pointer to a streambuf that can be pushed into buffer...

Most times when people have to reverse a string, they do it more or less like this: char[] a = s.ToCharArray(); System.Array.Reverse(a); string r = new string(a); However, what these people don't realize is that this is actually wrong. And I don't mean because of the missing NULL check. It ...

Creating backpressured data sources is the relatively easier task when dealing with backpressure in general because the library already offers static methods on Observable that handle backpressure for the developer. We can distinguish two kinds of factory methods: cold "generators" that ei...

At this point, you're still building your package, so you'll need to add the package to your application: meteor add myaccount:foo And eventually publish it to Atmosphere: meteor publish myaccount:foo

Now that we have all those pieces put together, you should now be able to make calls like the following from within your app: Foo.identify('John'); Foo.record_action_on_item('view', "HackerNews'); Obviously you'll want to adjust function names, arguments, urls, and the like, to create the ...

$ cat ip.txt address range substitution pattern sample Nth line $ sed -n '2p' ip.txt range $ sed '3d' ip.txt address range pattern sample Last line $ sed -n '$p' ip.txt sample

It's possible to send broadcast to BroadcastReceiver with adb. In this example we are sending broadcast with action com.test.app.ACTION and string extra in bundle 'foo'='bar': adb shell am broadcast -a action com.test.app.ACTION --es foo "bar" You can put any other supported type to b...

As well as being able to create an array by filtering out nil from the transformed elements of a sequence, there is also a version of flatMap(_:) that expects the transformation closure to return a sequence S. extension SequenceType { public func flatMap<S : SequenceType>(transform: (Sel...

Dart functions may also be declared anonymously or nested. For example, to create a nested function, just open a new function block within an existing function block void outerFunction() { bool innerFunction() { /// Does stuff } } The function innerFunction may now be us...

Here is an example of basic overriding in Python (for the sake of clarity and compatibility with both Python 2 and 3, using new style class and print with ()): class Parent(object): def introduce(self): print("Hello!") def print_name(self): print("Parent...

Having your scripts call Raycast directly may lead to problems if you need to change the collision matrices in the future, as you'll have to track down every LayerMask field to accommodate the changes. Depending on the size of your project, this may become a huge undertaking. Encapsulating Raycast ...

There are hundreds of settings that can be placed in my.cnf. For the 'lite' user of MySQL, they won't matter as much. Once your database becomes non-trivial, it is advisable to set the following parameters: innodb_buffer_pool_size This should be set to about 70% of available RAM (if you have a...

To uninstall Node.js on Windows, use Add or Remove Programs like this: Open Add or Remove Programs from the start menu. Search for Node.js. Windows 10: Click Node.js. Click Uninstall. Click the new Uninstall button. Windows 7-8.1: Click the Uninstall button under Node.js.

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