Tutorial by Examples: o

You can read an a binary file using this piece of code in all recent versions of Java: Java SE 1.4 File file = new File("path_to_the_file"); byte[] data = new byte[(int) file.length()]; DataInputStream stream = new DataInputStream(new FileInputStream(file)); stream.readFully(data); s...

static void Main(string[] args) { string url = "www.stackoverflow.com"; var pingTask = PingUrlAsync(url); Console.WriteLine($"Waiting for response from {url}"); Task.WaitAll(pingTask); Console.WriteLine(pingTask.Re...

A basic AppComponent that depends on a single AppModule to provide application-wide singleton objects. @Singleton @Component(modules = AppModule.class) public interface AppComponent { void inject(App app); Context provideContext(); Gson provideGson(); } A module to use to...

@Scope @Documented @Retention(RUNTIME) public @interface ActivityScope { } Scopes are just annotations and you can create your own ones where needed.

2.3 The CoordinatorLayout is a container somewhat similar to FrameLayout but with extra capabilities, it is called super-powered FrameLayout in the official documentation. By attaching a CoordinatorLayout.Behavior to a direct child of CoordinatorLayout, you’ll be able to intercept touch events, wi...

A String can be read from an InputStream using the byte array constructor. import java.io.*; public String readString(InputStream input) throws IOException { byte[] bytes = new byte[50]; // supply the length of the string in bytes here input.read(bytes); return new String(bytes); ...

java.util.Date to java.sql.Date conversion is usually necessary when a Date object needs to be written in a database. java.sql.Date is a wrapper around millisecond value and is used by JDBC to identify an SQL DATE type In the below example, we use the java.util.Date() constructor, that creates a D...

This code compiles: Integer arg = null; int x = arg; But it will crash at runtime with a java.lang.NullPointerException on the second line. The problem is that a primitive int cannot have a null value. This is a minimalistic example, but in practice it often manifests in more sophisticated f...

Sometimes a RecyclerView will need to use several types of Views to be displayed in the list shown in the UI, and each View needs a different layout xml to be inflated. For this issue, you may use different ViewHolders in single Adapter, by using a special method in RecyclerView - getItemViewType(i...

At run time the following would display a list of url in your console and continue computation payload = [{url:..., title:...}, {url=..., title=...}] main = payload |> List.map .url -- only takes the url |> Debug.log " My list of URLs" -- pass the url...

Cons-cells, structures, vectors, lists and such can be matched with constructor patterns. (loop for i from 1 to 30 do (format t "~5<~a~;~>" (match (cons (mod i 3) (mod i 5)) ((cons 0 0) "Fizzbuzz")...

CL-PPCRE:REGISTER-GROUPS-BIND will match a string against a regular expression, and if it matches, bind register groups in the regex to variables. If the string does not match, NIL is returned. (defun parse-date-string (date-string) (cl-ppcre:register-groups-bind (year month day) (...

A pointer to base class can be converted to a pointer to derived class using static_cast. static_cast does not do any run-time checking and can lead to undefined behaviour when the pointer does not actually point to the desired type. struct Base {}; struct Derived : Base {}; Derived d; Base* p1 ...

Simple Single Port RAM with one address for read/write operations. module ram_single #( parameter DATA_WIDTH=8, //width of data bus parameter ADDR_WIDTH=8 //width of addresses buses )( input [(DATA_WIDTH-1):0] data, //data to be written input [(ADDR_WIDTH-1):0] ad...

The shell provisioner runs a shell script when provisioning. $setup = <<SETUP # You can write your shell script between here ... sudo echo "Hello, World!" > /etc/motd.tail # ... and here. SETUP Vagrant.configure("2") do |config| config.vm.box = "ubuntu/tr...

Say you want to print variables in a 3 character column. Note: doubling { and } escapes them. s = """ pad {{:3}} :{a:3}: truncate {{:.3}} :{e:.3}: combined {{:>3.3}} :{a:>3.3}: {{:3.3}} :{a:3.3}: {{:3.3}} :{c:3...

A class, functions as a template that defines the basic characteristics of a particular object. Here's an example: class Person(object): """A simple class.""" # docstring species = "Homo Sapiens" ...

If logic of generic class or method requires checking equality of values having generic type, use EqualityComparer<TType>.Default property: public void Foo<TBar>(TBar arg1, TBar arg2) { var comparer = EqualityComparer<TBar>.Default; if (comparer.Equals(arg1,arg2) {...

By default the Large Object Heap is not compacted unlike the classic Object Heap which can lead to memory fragmentation and further, can lead to OutOfMemoryExceptions Starting with .NET 4.5.1 there is an option to explicitly compact the Large Object Heap (along with a garbage collection): GCSettin...

In Symfony it's possible to define multiple routes for one action. This can be very helpful if you have functions that do the same but have different parameters. class TestController extends Controller { /** * @Route("/test1/{id}", name="test") * @Route("/...