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In this example we have only one object but it is shared between/executed on different threads. Ordinary usage of fields to save state would not be possible because the other thread would see that too (or probably not see). public class Test { public static void main(String[] args) { ...

Sun / Oracle releases of Java SE come in two forms: JRE and JDK. In simple terms, JREs support running Java applications, and JDKs also support Java development. Java Runtime Environment Java Runtime Environment or JRE distributions consist of the set of libraries and tools needed to run and mana...

Orthogonal to the JRE versus JDK dichotomy, there are two types of Java release that are widely available: The Oracle Hotspot releases are the ones that you download from the Oracle download sites. The OpenJDK releases are the ones that are built (typically by third-party providers) from the Ope...

Here are some ways to set variables: You can set a variable to a specific, string, number, date using SET EX: SET @var_string = 'my_var'; SET @var_num = '2' SET @var_date = '2015-07-20'; you can set a variable to be the result of a select statement using := EX: Select @var := '123'; (...

To move to split on left, use <C-w><C-h> To move to split below, use <C-w><C-j> To move to split on right, use <C-w><C-k> To move to split above, use <C-w><C-l>

Assume you want to delegate to a class but you do not want to provide the delegated-to class in the constructor parameter. Instead, you want to construct it privately, making the constructor caller unaware of it. At first this might seem impossible because class delegation allows to delegate only to...

Here the steps required to create a Firebase project and to connect it with an Android app. Add Firebase to your app Create a Firebase project in the Firebase console and click Create New Project. Click Add Firebase to your Android app and follow the setup steps. When prompted, enter...

Sometimes you want an installation without anything except the bare minimum phoenix setup. The follow command will give you that. mix phoenix.new web --no-brunch --no-ecto Note: You must have installed Elixir, Erlang, Hex, Mix and the Phoenix archive for skeleton installation

All objects are instances of a class. However, that is not the whole truth. In Ruby, every object also has a somewhat hidden singleton class. This is what allows methods to be defined on individual objects. The singleton class sits between the object itself and its actual class, so all methods defi...

To detect multiple features at once, use the and operator. @supports (transform: translateZ(1px)) and (transform-style: preserve-3d) and (perspective: 1px) { /* Probably do some fancy 3d stuff here */ } There is also an or operator and a not operator: @supports (display: flex) or (display...

To better understand the semantics of conses and lists, a graphical representation of this kind of structures is often used. A cons cell is usually represented with two boxes in contact, that contain either two arrows that point to the car and cdr values, or directly the values. For instance, the re...

To consume a REST API with RestTemplate, create a Spring boot project with the Spring boot initialzr and make sure the Web dependency is added: <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dep...

Since JSON is stored textual column, you might want to ensure that it is properly formatted. You can add CHECK constraint on JSON column that checks is text properly formatted JSON: CREATE TABLE ProductCollection ( Id int identity primary key, Data nvarchar(max) CONSTRAINT [Data shoul...

PL/SQL uses IN, OUT, IN OUT keywords to define what can happen to a passed parameter. IN specifies that the parameter is read only and the value cannot be changed by the procedure. OUT specifies the parameter is write only and a procedure can assign a value to it, but not reference the value. IN ...

OPENJSON function parse JSON text and returns all key:value pairs at the first level of JSON: declare @json NVARCHAR(4000) = N'{"Name":"Joe","age":27,"skills":["C#","SQL"]}'; SELECT * FROM OPENJSON(@json); keyvaluetypeNameJoe1age272ski...

OPENJSON function parses collection of JSON objects and returns values from JSON text as set of rows. declare @json nvarchar(4000) = N'[ {"Number":"SO43659","Date":"2011-05-31T00:00:00","Customer": "MSFT","Price":59.99,"Q...

OPENJSON function parses collection of JSON objects and returns values from JSON text as set of rows. If the values in input object are nested, additional mapping parameter can be specified in each column in WITH clause: declare @json nvarchar(4000) = N'[ {"data":{"num":&quot...

$router = new \Phalcon\Mvc\Router(false); $router->removeExtraSlashes(true); $request = new \Phalcon\Http\Request(); $action = strtolower($request->getMethod()); // get, post, etc. $modules = ['calendar', 'main', 'user']; // names of the modules you create // you can define other static...

A list consists of <li> elements inside a containing element (<ul> or <ol>). Both the list items and the container can have margins and paddings which influence the exact position of the list item content in the document. The default values for the margin and padding may be differe...

Sometimes, a list should just not display any bullet points or numbers. In that case, remember to specify margin and padding. <ul> <li>first item</li> <li>second item</li> </ul> CSS ul { list-style-type: none; } li { margin: 0; pad...