Tutorial by Examples: on

To encode a string into a byte array, you can simply use the String#getBytes() method, with one of the standard character sets available on any Java runtime: byte[] bytes = "test".getBytes(StandardCharsets.UTF_8); and to decode: String testString = new String(bytes, StandardCharsets.U...

Functions can return tuples: func tupleReturner() -> (Int, String) { return (3, "Hello") } let myTuple = tupleReturner() print(myTuple.0) // 3 print(myTuple.1) // "Hello" If you assign parameter names, they can be used from the return value: func tupleReturner(...

Java SE 5 public enum Singleton { INSTANCE; public void execute (String arg) { // Perform operation here } } Enums have private constructors, are final and provide proper serialization machinery. They are also very concise and lazily initialized in a thread safe manne...

HTTPGetJSON performs an HTTP request to the specified URL and returns a jsonq.JsonQuery object for use in the alert template. Example: template example { {{ $ip := 8.8.8.8 }} {{ $whoisURL := printf "http://whois.arin.net/rest/ip/%s" $ip }} {{ $whoisJQ := $.HTTPGetJSON $who...

Here is an example of a Bosun config file used in a development environment: tsdbHost = localhost:4242 httpListen = :8070 smtpHost = localhost:25 emailFrom = [email protected] timeAndDate = 202,75,179,136 ledisDir = ../ledis_data checkFrequency = 5m notification example.notification { ...

All instances of Preferences are always thread-safe across the threads of a single Java Virtual Machine (JVM). Because Preferences can be shared across multiple JVMs, there are special methods that deal with synchronizing changes across virtual machines. If you have an application which is supposed...

A very common guideline in object oriented design is "as little as possible but as much as necessary". This also applies to the strategy pattern: It is usually advisable to hide implementation details, for example which classes actually implement strategies. For simple strategies which do...

Iterators and pointers pointing into an std::vector can become invalid, but only when performing certain operations. Using invalid iterators/pointers will result in undefined behavior. Operations which invalidate iterators/pointers include: Any insertion operation which changes the capacity of...

This uses the Dropbox Python SDK to upload a file to the Dropbox API from the local file as specified by file_path to the remote path as specified by dest_path. It also chooses whether or not to use an upload session based on the size of the file: f = open(file_path) file_size = os.path.getsize(fi...

Useful for simple animations, the CSS transition property allows number-based CSS properties to animate between states. Example .Example{ height: 100px; background: #fff; } .Example:hover{ height: 120px; background: #ff0000; } View Result By default, hovering over an...

When creating animations and other GPU-heavy actions, it's important to understand the will-change attribute. Both CSS keyframes and the transition property use GPU acceleration. Performance is increased by offloading calculations to the device's GPU. This is done by creating paint layers (parts of...

For multi-stage CSS animations, you can create CSS @keyframes. Keyframes allow you to define multiple animation points, called a keyframe, to define more complex animations. Basic Example In this example, we'll make a basic background animation that cycles between all colors. @keyframes rainbow...

This example uses the Dropbox .NET library to try to get the metadata for an item at a particular path, and checks for a NotFound error: try { var metadata = await this.client.Files.GetMetadataAsync("/non-existant path"); Console.WriteLine(metadata.Name); } catch (Dropbox.Api.A...

Constructor injection is the safest way of injecting dependencies that a whole class depends upon. Such dependencies are often referred to as invariants, since an instance of the class cannot be created without supplying them. By requiring the dependency to be injected at construction, it is guara...

Property injection allows a classes dependencies to be updated after it has been created. This can be useful if you want to simplify object creation, but still allow the dependencies to be overridden by your tests with test doubles. Consider a class that needs to write to a log file in an error co...

Method injection is a fine grained way of injecting dependencies into processing. Consider a method that does some processing based on the current date. The current date is hard to change from a test, so it is much easier to pass a date into the method that you want to test. public void ProcessRe...

Whilst extracting dependencies out of your code so that they can be injected makes your code easier to test, it pushes the problem further up the hierarchy and can also result in objects that are difficult to construct. Various dependency injection frameworks / Inversion of Control Containers have ...

A controller is a basic structure used in Angular to preserve scope and handle certain actions within a page. Each controller is coupled with an HTML view. Below is a basic boilerplate for an Angular app: <!DOCTYPE html> <html lang="en" ng-app='MyFirstApp'> <head...

Dim input as String = Console.ReadLine() Console.ReadLine() will read the console input from the user, up until the next newline is detected (usually upon pressing the Enter or Return key). Code execution is paused in the current thread until a newline is provided. Afterwards, the next line of co...

Dim x As Int32 = 128 Console.WriteLine(x) ' Variable ' Console.WriteLine(3) ' Integer ' Console.WriteLine(3.14159) ' Floating-point number ' Console.WriteLine("Hello, world") ' String ' Console.WriteLine(myObject) ' Outputs the value from calling myObject.ToString() The Console.Wri...