Tutorial by Examples: p

You can require a generic type to extend multiple upper bounds. Example: we want to sort a list of numbers but Number doesn't implement Comparable. public <T extends Number & Comparable<T>> void sortNumbers( List<T> n ) { Collections.sort( n ); } In this example T must...

Auto-implemented properties were introduced in C# 3. An auto-implemented property is declared with an empty getter and setter (accessors): public bool IsValid { get; set; } When an auto-implemented property is written in your code, the compiler creates a private anonymous field that can only be...

Lets assume we have some Film model: public class Film { public string Title { get; set; } public string Category { get; set; } public int Year { get; set; } } Group by Category property: foreach (var grp in films.GroupBy(f => f.Category)) { var groupCategory = grp.Key; ...

Definition In software development, a breakpoint is an intentional stopping or pausing place in a program, put in place for debugging purposes. More generally, a breakpoint is a means of acquiring knowledge about a program during its execution. During the interruption, the programmer inspects th...

The following code snippet shows how to open the Google Play Store Listing of your app in a safe way. Usually you want to use it when asking the user to leave a review for your app. private void openPlayStore() { String packageName = getPackageName(); Intent playStoreIntent = new Intent(I...

Swift supports the creation of custom operators. New operators are declared at a global level using the operator keyword. The operator's structure is defined by three parts: operand placement, precedence, and associativity. The prefix, infix and postfix modifiers are used to start an custom op...

Sqoop ships as one binary package however it’s compound from two separate parts client and server. You need to install server on single node in your cluster. This node will then serve as an entry point for all connecting Sqoop clients. Server acts as a mapreduce client and therefore Hadoop must b...

To jump back to a previous commit, first find the commit's hash using git log. To temporarily jump back to that commit, detach your head with: git checkout 789abcd This places you at commit 789abcd. You can now make new commits on top of this old commit without affecting the branch your head is...

To get a verbose list of all devices connected to adb, write the following command in your terminal: adb devices -l Example Output List of devices attached ZX1G425DC6 device usb:336592896X product:shamu model:Nexus_6 device:shamu 013e4e127e59a868 device usb:337641472X produc...

Write the following command in your terminal: adb install [-rtsdg] <file> Note that you have to pass a file that is on your computer and not on your device. If you append -r at the end, then any existing conflicting apks will be overwritten. Otherwise, the command will quit with an error....

Write the following command in your terminal to uninstall an app with a provided package name: adb uninstall <packagename>

The example shows parsing a JSON object using the Gson library from Google. Parsing objects: class Robot { //OPTIONAL - this annotation allows for the key to be different from the field name, and can be omitted if key and field name are same . Also this is good coding practice as it decouple ...

Prerequisites To run the Play framework, you need Java 6 or later. If you wish to build Play from source, you will need the Git source control client to fetch the source code and Ant to build it. Be sure to have Java in the current path (enter java --version to check) Play will use the default Ja...

Composer is a dependency/package manager for PHP. It can be used to install, keep track of, and update your project dependencies. Composer also takes care of autoloading the dependencies that your application relies on, letting you easily use the dependency inside your project without worrying about...

While composer provides a system to manage dependencies for PHP projects (e.g. from Packagist), it can also notably serve as an autoloader, specifying where to look for specific namespaces or include generic function files. It starts with the composer.json file: { // ... "autoload&q...

Ember comes with a built in helper that will provide computed properties for the status of an asynchronous task. Pros Built in – no need for an addon. Can be managed in the life cycle of a component. Provides convenient state properties that can drive the template logic. Cons Must be wra...

After creating a new model or modifying existing models, you will need to generate migrations for your changes and then apply the migrations to the specified database. This can be done by using the Django's built-in migrations system. Using the manage.py utility when in the project root directory: ...

We can name our loops and break the specific one when necessary. outerloop: for (var i = 0;i<3;i++){ innerloup: for (var j = 0;j <3; j++){ console.log(i); console.log(j); if (j == 1){ break outerloop; } } } Output: 0 0...

Detailed instructions on getting asp.net-web-api set up or installed.

All looping constructs allow the use of break and continue statements. They affect the immediately surrounding (innermost) loop. Basic Loop Control break terminates the loop: for x in 0..5 { if x > 2 { break; } println!("{}", x); } Output 0 1 2 continue finishes...