Tutorial by Examples: b

This method can be used to convert a formatted string representation of a date into a Date object. /** * Parses the date using the given format. * * @param formattedDate the formatted date string * @param dateFormat the date format which was used to create the string. ...

The base keyword is used to access members from a base class. It is commonly used to call base implementations of virtual methods, or to specify which base constructor should be called. Choosing a constructor public class Child : SomeBaseClass { public Child() : base("some string for th...

To find files/directories with a specific name, relative to pwd: $ find . -name "myFile.txt" ./myFile.txt To find files/directories with a specific extension, use a wildcard: $ find . -name "*.txt" ./myFile.txt ./myFile2.txt To find files/directories matching one of ma...

To find files, use the -type f flag $ find . -type f To find directories, use the -type d flag $ find . -type d To find block devices, use the -type b flag $ find /dev -type b To find symlinks, use the -type l flag $ find . -type l

lscount returns a time bucketed count of matching documents in the LogStash index, according to the specified filter. A trivial use of this would be to check how many documents in total have been received in the 5 minutes, and alert if it is below a certain threshold. A Bosun alert for this might ...

At its simplest, a unit test consists of three stages: Prepare the environment for the test Execute the code to be tested Validate the expected behaviour matches the observed behaviour These three stages are often called 'Arrange-Act-Assert', or 'Given-When-Then'. Below is example in C# tha...

#include <stdio.h> #define is_const_int(x) _Generic((&x), \ const int *: "a const int", \ int *: "a non-const int", \ default: "of other type") int main(void) { const int i = 1; int j = 1; double...

A lambda expression provides a concise way to create simple function objects. A lambda expression is a prvalue whose result object is called closure object, which behaves like a function object. The name 'lambda expression' originates from lambda calculus, which is a mathematical formalism invented...

If you specify the variable's name in the capture list, the lambda will capture it by value. This means that the generated closure type for the lambda stores a copy of the variable. This also requires that the variable's type be copy-constructible: int a = 0; [a]() { return a; // Ok, 'a' ...

On an ext filesystem, each file has a stored Access, Modification, and (Status) Change time associated with it - to view this information you can use stat myFile.txt; using flags within find, we can search for files that were modified within a certain time range. To find files that have been modifi...

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...

Tuples can be decomposed into individual variables with the following syntax: let myTuple = (name: "Some Name", age: 26) let (first, second) = myTuple print(first) // "Some Name" print(second) // 26 This syntax can be used regardless of if the tuple has unnamed properti...

In this example we're going to look at testing webhook notifications in sandbox, using ngrok to provide a tunnel for our Node HTTP listener, running on localhost, to the internet. For this example, we're going to be using Node to set up notification webhooks for payment events (such as a payment bei...

Occasionally you will find the need to encode binary data as a base64-encoded string. For this we can use the DatatypeConverter class from the javax.xml.bind package: import javax.xml.bind.DatatypeConverter; import java.util.Arrays; // arbitrary binary data specified as a byte array byte[] bi...

Writing bytes to an OutputStream one byte at a time OutputStream stream = object.getOutputStream(); byte b = 0x00; stream.write( b ); Writing a byte array byte[] bytes = new byte[] { 0x00, 0x00 }; stream.write( bytes ); Writing a section of a byte array int offset = 1; int length = ...

This sample will show you how to update an existing webhook forwarding URL (where the notifications should be POSTed to). To run this, you should have the ID provided back by PayPal when you first created your webhooks. First, add the PayPal SDK and configure the environment (sandbox below). var p...

Java SE 7 byte[] bytes = { 0x48, 0x65, 0x6c, 0x6c, 0x6f }; try(FileOutputStream stream = new FileOutputStream("Hello world.txt")) { stream.write(bytes); } catch (IOException ioe) { // Handle I/O Exception ioe.printStackTrace(); } Java SE 7 byte[] bytes = { 0x48, ...

With Stream Controller add-on enabled, you can use Channel Groups to subscribe to a 1000's of channels from a single client. You do this by creating a channel group and adding channels to the channel group. We'll assume pubnub variable has been initialized properly with your keys. Create a generic ...

Preferences objects always represent a specific node in a whole Preferences tree, kind of like this: /userRoot ├── com │   └── mycompany │   └── myapp │   ├── darkApplicationMode=true │   ├── showExitConfirmation=false │   └── windowMaximized=true └── org └...

Note that all bitwise operations operate on 32-bit integers by passing any operands to the internal function ToInt32. Bitwise or var a; a = 0b0011 | 0b1010; // a === 0b1011 // truth table // 1010 | (or) // 0011 // 1011 (result) Bitwise and a = 0b0011 & 0b1010; // a === 0b0010 // t...