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javascript.html
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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<link rel="shortcut icon" href="assets/img/mainlogo.jpg" type="image/x-icon">
<title>Home</title>
<link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css" rel="stylesheet"
integrity="sha384-Zenh87qX5JnK2Jl0vWa8Ck2rdkQ2Bzep5IDxbcnCeuOxjzrPF/et3URy9Bv1WTRi" crossorigin="anonymous" />
<link rel="stylesheet" href="assets/css/style.css" />
<link rel="stylesheet" href="assets/prismjs/prism.css" />
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js"
integrity="sha384-OERcA2EqjJCMA+/3y+gxIOqMEjwtxJY7qPCqsdltbNJuaOe923+mo//f6V8Qbsw3"
crossorigin="anonymous"></script>
<link rel="stylesheet" href="myDesigns/assets/bootstrap/css/bootstrap.min.css">
<link rel="stylesheet"
href="https://fonts.googleapis.com/css?family=Source+Sans+Pro:300,400,700,300italic,400italic,700italic">
<link rel="stylesheet" href="myDesigns/assets/fonts/font-awesome.min.css">
<link rel="stylesheet" href="myDesigns/assets/fonts/simple-line-icons.min.css">
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/font/bootstrap-icons.css" />
<style>
.scroll-to-top {
background-color: #f77b50 !important;
text-decoration: none !important;
}
.scroll-to-top:hover {
background: #f77b50 !important;
text-decoration: none !important;
}
footer .scroll-to-top {
text-decoration: none !important;
}
.offcanvas {
width: 700px !important; /* Override the default width */
}
</style>
</head>
<body id="page-top">
<nav class="navbar fixed-top navbar-expand-lg navbar-dark" style="background-color: rgb(1,4,45);">
<div class="container-fluid">
<a class="navbar-brand" href="index.php">
<img src="assets/img/mainlogo.jpg" alt="" style="height: 7vh;"> Cheatbook
</a>
<button class="navbar-toggler" type="button" data-bs-toggle="collapse"
data-bs-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false"
aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav me-auto mb-2 mb-lg-0">
<li class="nav-item">
<a class="nav-link active" aria-current="page" href="index.php">Home</a>
</li>
<!--frontend -->
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Frontend
</a>
<ul class="dropdown-menu multi-column columns-2">
<div class="row">
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li><a class="dropdown-item" href="html.php">HTML</a></li>
<li><a class="dropdown-item" href="css.php">CSS</a></li>
<li><a class="dropdown-item"
href="javascript.php">JavaScript</a></li>
<li><a class="dropdown-item"
href="typescript.php">TypeScript</a></li>
<li>
<hr class="dropdown-divider" />
</li>
<li class="dropdown-header">JavaScript Frameworks</li>
<li><a class="dropdown-item" href="reactjs.php">Reacjs</a></li>
<li><a class="dropdown-item" href="nextjs.php">Nextjs</a></li>
<li><a class="dropdown-item"
href="angularjs.php">Angularjs</a></li>
<li><a class="dropdown-item" href="remix.php">Remixjs</a></li>
<li><a class="dropdown-item" href="vuejs.php">vuejs</a></li>
</ul>
</div>
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li><a class="dropdown-item" href="astrojs.php">Astrojs</a></li>
<li><a class="dropdown-item" href="electronjs.php">electronjs</a></li>
<li>
<hr class="dropdown-divider" />
</li>
<li class="dropdown-header">CSS Framework</li>
<li><a class="dropdown-item" href="bootstrap.php">Bootstrap</a></li>
<li><a class="dropdown-item" href="tailwindcss.php">Tailwind css</a></li>
<li><a class="dropdown-item" href="materialui.php">Material UI</a></li>
<li> <hr class="dropdown-divider" /> </li>
<li class="dropdown-header">State Management</li>
<li><a class="dropdown-item" href="redux.php">Redux</a></li>
</ul>
</div>
</div>
</ul>
</li>
<!-- backend -->
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Backend
</a>
<ul class="dropdown-menu multi-column columns-2">
<div class="row">
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li><a class="dropdown-item" href="django.php">Django</a></li>
<li><a class="dropdown-item" href="flask.php">Flask</a></li>
<li><a class="dropdown-item" href="fastapi.php">Fastapi</a></li>
<li><a class="dropdown-item" href="expressjs.php">Expressjs</a></li>
<li><a class="dropdown-item" href="nodejs.php">Nodejs</a></li>
<li><a class="dropdown-item" href="php.php">PHP</a></li>
<li><a class="dropdown-item" href="golang.php">GO</a></li>
<li><a class="dropdown-item" href="spring.php">Spring</a></li>
<li><a class="dropdown-item"href="springboot.php">Springboot</a></li>
<li> <hr class="dropdown-divider" /></li>
<li class="dropdown-header">Databases</li>
<li><a class="dropdown-item" href="Sql.php">SQL</a></li>
</ul>
</div>
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li><a class="dropdown-item" href="mysql.php">MySQL</a></li>
<li><a class="dropdown-item" href="mongodb.php">MongoDB</a></li>
<li><a class="dropdown-item" href="firebase.php">Firebase</a></li>
<li><a class="dropdown-item" href="cassandra.php">Cassandra</a></li>
<li><a class="dropdown-item" href="redis.php">Redis</a></li>
<li><a class="dropdown-item" href="postgresql.php">PostgreSQL</a></li>
<li><a class="dropdown-item" href="influxdb.php">infixDB</a></li>
<li> <hr class="dropdown-divider" /> </li>
<li class="dropdown-header">Java technologies</li>
<li><a class="dropdown-item" href="hibernet.php">Hibernet</a></li>
<li><a class="dropdown-item" href="jdbc.php">jdbc</a></li>
<li><a class="dropdown-item" href="servlets.php">servlets</a></li>
</ul>
</div>
</div>
</ul>
</li>
<!-- programming -->
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Programming
</a>
<ul class="dropdown-menu multi-column columns-2">
<div class="row">
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li><a class="dropdown-item" href="cplus.php">C++</a></li>
<li><a class="dropdown-item" href="c.php">C</a></li>
<li><a class="dropdown-item" href="java.php">Java</a></li>
<li><a class="dropdown-item" href="python.php">Python</a></li>
</ul>
</div>
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li class="dropdown-header">Data structure</li>
<li><a class="dropdown-item" href="dsa.php">DSA</a></li>
</ul>
</div>
</div>
</ul>
</li>
<!-- databases -->
<li class="nav-item dropdown mx-1">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Design
</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="figma.php">Figma</a></li>
<li><a class="dropdown-item" href="adobexd.php">AdobeXD</a></li>
</ul>
</li>
<!-- API & Authentication -->
<li class="nav-item dropdown mx-1">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
API & Auth
</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="restfulapi.php">RESTful API</a></li>
<li><a class="dropdown-item" href="graphql.php">GraphQL</a></li>
<li><a class="dropdown-item" href="jwtauth.php">JWT Auth</a></li>
<li><a class="dropdown-item" href="apollo.php">Apollo</a></li>
</ul>
</li>
<!-- testing -->
<li class="nav-item dropdown mx-1">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Testing
</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="jest.php">Jest</a></li>
</ul>
</li>
<!-- cloud services -->
<li class="nav-item dropdown mx-1">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Cloud
</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="aws.php">AWS</a></li>
<li><a class="dropdown-item" href="azure.php">Azure</a></li>
<li><a class="dropdown-item" href="googlecloud.php">Google Cloud</a></li>
<li><a class="dropdown-item" href="cloudflare.php">Cloudflare</a></li>
</ul>
</li>
<!-- Mobile Development-->
<li class="nav-item dropdown mx-1">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Mobile Dev
</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="android.php">Android</a></li>
<li><a class="dropdown-item" href="kotlin.php">Kotlin</a></li>
<li><a class="dropdown-item" href="reactnative.php">React Native</a></li>
<li><a class="dropdown-item" href="flutter.php">Flutter</a></li>
</ul>
</li>
<!-- Devops -->
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Devops
</a>
<ul class="dropdown-menu multi-column columns-2">
<div class="row">
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<li class="dropdown-header">CI/CD</li>
<li><a class="dropdown-item" href="docker.php">Docker</a></li>
<li><a class="dropdown-item" href="jenkins.php">jenkins</a></li>
<li><a class="dropdown-item" href="kubernetes.php">kubernetes</a></li>
<li><a class="dropdown-item" href="maven.php">Maven</a></li>
<li><a class="dropdown-item" href="git.php">Git</a> </li>
<li><a class="dropdown-item" href="github_action.php">Github Actions</a></li>
<li><a class="dropdown-item" href="Terraform.php">Terraform</a></li>
<li><a class="dropdown-item" href="ansible.php">Ansible</a></li>
<li><hr class="dropdown-divider" /></li>
<li class="dropdown-header">Web Servers</li>
<li><a class="dropdown-item" href="languages/devops/nginx.php">Nginx</a>
</li>
</ul>
</div>
<div class="col-sm-6">
<ul class="multi-column-dropdown">
<hr class="dropdown-divider" />
</li>
<li class="dropdown-header">Operating System</li>
<li><a class="dropdown-item" href="windows.php">Windows</a>
</li>
<li><a class="dropdown-item" href="linux.php">Linux</a>
</li>
<li><a class="dropdown-item" href="macos.php">Macos</a>
</li>
<li>
<hr class="dropdown-divider" />
</li>
<li class="dropdown-header">Scripting</li>
<li><a class="dropdown-item" href="bashscript.php">Bash Scripting</a>
</li>
<li>
<hr class="dropdown-divider" />
</li>
<li class="dropdown-header">Monitoring</li>
<li><a class="dropdown-item" href="monit.php">Monit</a>
</ul>
</div>
</div>
</ul>
</li>
<li class="nav-item">
<a class="nav-link" href="about.php">About Us</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown"
aria-expanded="false">
Tools
</a>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="tools/shadowpicker/index.html">Shadow Picker</a></li>
<li><a class="dropdown-item" href="tools/readmemaker/index.html">Github Project Readme</a>
</li>
<li><a class="dropdown-item" href="tools/profilereadme/index.html">Github Profile Readme</a>
</li>
<li><a class="dropdown-item" href="tools/gradientcolorpicker.html">Gradient Colour
Picker</a></li>
<li><a class="dropdown-item" href="tools/colourbook/colorpiceker.html">Colour Picker</a>
</li>
<li><a class="dropdown-item" href="tools/codereview/index.html">Simple Code Editor</a> </li>
<li><a class="dropdown-item" href="tools/banner/index.html">Banner Maker</a> </li>
<li><a class="dropdown-item" href="tools/logomaker/index.html">Logo & Favicon Maker</a>
</li>
<li><a class="dropdown-item" href="tools/paraiso-colors-main/index.html">colour plates</a>
</li>
</ul>
</li>
</ul>
<a href="myDesigns/index.html">
<div class="button btn1 mx-1" style="font-size: 1em;">My Designs</div>
</a>
</div>
</div>
</nav> <!-- mid part -->
<nav class="mt-5 p-2 headline" style="background:linear-gradient(to top right, #fb5475 0%, #f77b50 59%);">
<div class="text-center " style="margin-top:5vh;"><img style="margin-right:2vh;" src="../../assets/img/javascript-icon.svg" alt="" />JavaScript Cheatsheet
</div>
</nav>
<div class="container">
<div class="p-5 mb-4 bg-light rounded-3 jumbo mt-2">
<div class="container-fluid py-3">
<h1 class="display-5 fw-bold">JavaScript</h1>
<div class="row">
<div class="col-md-8">
<p class="fs-4">
Java is a popular programming language, created in 1995.
<br> It is owned by Oracle, and more than 3 billion devices run Java.
<br> It is used for:
<br>
<ul>
<li>
Mobile applications (specially Android apps)</li>
<li> Desktop applications</li>
<li> Web applications</li>
<li> Web servers and application servers</li>
<li> Games</li>
<li>Database connection</li>
<li> And much, much more!</li>
</ul>
</p>
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Java
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<ol type="a">
<li>Java works on different platforms (Windows, Mac, Linux, Raspberry Pi, etc.)</li>
<li>It is one of the most popular programming language in the world</li>
<li> It has a large demand in the current job market</li>
<li> It is easy to learn and simple to use</li>
<li> It is open-source and free</li>
<li>It is secure, fast and powerful</li>
<li>It has a huge community support (tens of millions of developers)</li>
<li>Java is an object oriented language which gives a clear structure to programs and allows code to be reused, lowering development costs</li>
<li>As Java is close to C++ and C#, it makes it easy for programmers to switch to Java or vice versa</li>
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Java Syntax<button class="btn btn1" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasBottom2" aria-controls="offcanvasBottom">Read more...</button>
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The curly braces {} marks the beginning and the end of a block of code.
<br><br> System is a built-in Java class that contains useful members, such as out, which is short for "output". The println() method, short for "print line", is used to print a value to the screen (or a file).
<br><br> Don't worry too much about System, out and println(). Just know that you need them together to print stuff to the screen.
<br><br> You should also note that each code statement must end with a semicolon (;).
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<pre class="language-java">
<code>
public class Main {
public static void main(String[] args) {
System.out.println("Hello World");
}
}
</code>
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1) The Print() Method<br> There is also a print() method, which is similar to println(). <br> The only difference is that it does not insert a new line at the end of the output
<br><br><br>2) Println() <br> You can add as many println() methods as you want. Note that it will add a new line for each method
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<h3>Print()</h3>
<pre class="language-java">
<code>
System.out.print("I will print on the same line.");
</code>
</pre>
<h3>Println()</h3>
<pre class="language-java">
<code>
System.out.println("Hello World!");
</code>
</pre>
</li>
<li>Java Comments
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Comments can be used to explain Java code, and to make it more readable. It can also be used to prevent execution when testing alternative code.
<br><br> Single-line Comments<br> Single-line comments start with two forward slashes (//).
<br> Any text between // and the end of the line is ignored by Java (will not be executed).
<br><br>Java Multi-line Comments<br> Multi-line comments start with /* and ends with */.
<br> Any text between /* and */ will be ignored by Java.
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<h3>single linecomment</h3>
<pre class="language-java">
<code>
// This is a comment
</code>
</pre>
<h3>Multi-Line comments</h3>
<pre class="language-java">
<code>
/* The code below will print the words Hello World
to the screen, and it is amazing */
</code>
</pre>
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Variables are containers for storing data values.
<br><br> In Java, there are different types of variables, for example:
<br>
<ol>
<li>String - stores text, such as "Hello". String values are surrounded by double quotes
</li>
<li>int - stores integers (whole numbers), without decimals, such as 123 or -123
</li>
<li>float - stores floating point numbers, with decimals, such as 19.99 or -19.99
</li>
<li>char - stores single characters, such as 'a' or 'B'. Char values are surrounded by single quotes</li>
<li>boolean - stores values with two states: true or false
</li>
</ol><br><br> Final Variables <br> If you don't want others (or yourself) to overwrite existing values, use the final keyword (this will declare the variable as "final" or "constant", which means unchangeable and read-only)
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<h3>Declaring (Creating) Variables (Syntax)</h3>
<pre class="language-java">
<code>
type variableName = value;
</code>
</pre>
<h3>Final Variables</h3>
<pre class="language-java">
<code>
final int myNum = 15;
</code>
</pre>
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<li>
Identifiers<button class="btn btn1" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvas2" aria-controls="offcanvasBottom">Read more...</button>
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All Java variables must be identified with unique names.
<br> These unique names are called identifiers.
<br> Identifiers can be short names (like x and y) or more descriptive names (age, sum, totalVolume).
<br><br> Note: It is recommended to use descriptive names in order to create understandable and maintainable code
<br><br> The general rules for naming variables are:
<br> Names can contain letters, digits, underscores, and dollar signs<br> Names must begin with a letter<br> Names should start with a lowercase letter and it cannot contain whitespace<br> Names can also begin with $ and _ (but
we will not use it in this tutorial)<br> Names are case sensitive ("myVar" and "myvar" are different variables)<br> Reserved words (like Java keywords, such as int or boolean) cannot be used as names <br>
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<li>Java Data Types
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Data types are divided into two groups:
<br> <br> 1)Primitive data types - includes byte, short, int, long, float, double, boolean and char
<br> 2)Non-primitive data types - such as String, Arrays and Classes (you will learn more about these in a later chapter) <br>Non-primitive data types are called reference types because they refer to objects.
<br> The main difference between primitive and non-primitive data types are:
<br> Primitive types are predefined (already defined) in Java. Non-primitive types are created by the programmer and is not defined by Java (except for String).
<br>Non-primitive types can be used to call methods to perform certain operations, while primitive types cannot.<br> A primitive type has always a value, while non-primitive types can be null.
<br>A primitive type starts with a lowercase letter, while non-primitive types starts with an uppercase letter.<br> The size of a primitive type depends on the data type, while non-primitive types have all the same size. <br> <br> 1) Primitive Data Types <br> A primitive data type specifies the size and type of variable values, and it has no additional methods.
<br> There are eight primitive data types in Java: <br> <br>
<table class="ws-table-all notranslate table-bordered">
<tbody>
<tr>
<th style="width:20%">Data Type</th>
<th style="width:17%">Size</th>
<th style="width:63%">Description</th>
</tr>
<tr>
<td><code class="w3-codespan">byte</code></td>
<td>1 byte</td>
<td>Stores whole numbers from -128 to 127</td>
</tr>
<tr>
<td><code class="w3-codespan">short</code></td>
<td>2 bytes</td>
<td>Stores whole numbers from -32,768 to 32,767</td>
</tr>
<tr>
<td><code class="w3-codespan">int</code></td>
<td>4 bytes</td>
<td>Stores whole numbers from -2,147,483,648 to 2,147,483,647</td>
</tr>
<tr>
<td><code class="w3-codespan">long</code></td>
<td>8 bytes</td>
<td>Stores whole numbers from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
</td>
</tr>
<tr>
<td><code class="w3-codespan">float</code></td>
<td>4 bytes</td>
<td>Stores fractional numbers. Sufficient for storing 6 to 7 decimal digits</td>
</tr>
<tr>
<td><code class="w3-codespan">double</code></td>
<td>8 bytes</td>
<td>Stores fractional numbers. Sufficient for storing 15 decimal digits</td>
</tr>
<tr>
<td><code class="w3-codespan">boolean</code></td>
<td>1 bit</td>
<td>Stores true or false values</td>
</tr>
<tr>
<td><code class="w3-codespan">char</code></td>
<td>2 bytes</td>
<td>Stores a single character/letter or ASCII values</td>
</tr>
</tbody>
</table>
<br><br> Primitive number types are divided into two groups:
<br><br> A) Integer types stores whole numbers, positive or negative (such as 123 or -456), without decimals. Valid types are byte, short, int and long. Which type you should use, depends on the numeric value.
<br> <br><br> B) Floating point types represents numbers with a fractional part, containing one or more decimals. There are two types: float and double.
<br><br>3)Boolean Types:Very often in programming, you will need a data type that can only have one of two values, like:
<br><br> YES / NO<br> ON / OFF<br> TRUE / FALSE<br> For this, Java has a boolean data type, which can only take the values true or false
<br><br> 4)Characters: <br> The char data type is used to store a single character. The character must be surrounded by single quotes, like 'A' or 'c' <br><br> 5)Strings: <br> The String data type is used to store a sequence of
characters (text). String values must be surrounded by double quotes
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<h3>Premitive number type : Integer type</h3>
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long myNum = 15000000000L;
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<br><br>
<h3>Premitive number type : Floating Point Types</h3>
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<code>
double d1 = 12E4d;
</code>
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</div>
<br><br>
<h3>Boolean Types</h3>
<pre class="language-java">
<code>
boolean isJavaFun = true;
</code>
</pre>
<br>
<h3>Characters</h3>
<pre class="language-java">
<code>
char myGrade = 'B';
</code>
</pre>
<br>
<h3>Strings</h3>
<pre class="language-java">
<code>
String greeting = "Hello World";
</code>
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Java Type Casting<button class="btn btn1" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasBottom10" aria-controls="offcanvasBottom">Read more...</button>
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Type casting is when you assign a value of one primitive data type to another type.
<br> In Java, there are two types of casting:
<br> Widening Casting (automatically) - converting a smaller type to a larger type size byte -> short -> char -> int -> long -> float -> double
<br><br> Narrowing Casting (manually) - converting a larger type to a smaller size type double -> float -> long -> int -> char -> short -> byte
</div>
</div>
<h3>Widening Casting</h3>
<pre class="language-java">
<code>
int myInt = 9;
double myDouble = myInt; // Automatic casting: int to double
</code>
</pre>
<h3>Narrowing Casting</h3>
<pre class="language-java">
<code>
double myDouble = 9.78d;
int myInt = (int) myDouble; // Manual casting: double to int
</code>
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<li>Java Operators<button class="btn btn1" type="button" data-bs-toggle="offcanvas" data-bs-target="#offcanvasBottom12" aria-controls="offcanvasBottom">Read more...</button>
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Operators are used to perform operations on variables and values.
<br><br> Java divides the operators into the following groups:
<br> 1) Arithmetic operators<br> 2) Assignment operators<br> 3) Comparison operators<br> 4) Logical operators<br> 5) Bitwise operators <br><br><br> 1)Arithmetic Operators <br> Arithmetic operators are used to perform common mathematical
operations.
<table class="ws-table-all notranslate table-bordered">
<tbody>
<tr>
<th style="width:15%">Operator</th>
<th style="width:18%">Name</th>
<th style="width:50%">Description</th>
<th style="width:17%;">Example</th>
</tr>
<tr>
<td>+</td>
<td>Addition</td>
<td>Adds together two values</td>
<td>x + y</td>
</tr>
<tr>
<td>-</td>
<td>Subtraction</td>
<td>Subtracts one value from another</td>
<td>x - y</td>
</tr>
<tr>
<td>*</td>
<td>Multiplication</td>
<td>Multiplies two values</td>
<td>x * y</td>
</tr>
<tr>
<td>/</td>
<td>Division</td>
<td>Divides one value by another</td>
<td>x / y</td>
</tr>
<tr>
<td>%</td>
<td>Modulus</td>
<td>Returns the division remainder</td>
<td>x % y</td>
</tr>
<tr>
<td>++</td>
<td>Increment</td>
<td>Increases the value of a variable by 1</td>
<td>++x</td>
</tr>
<tr>
<td>--</td>
<td>Decrement</td>
<td>Decreases the value of a variable by 1</td>
<td>--x</td>
</tr>
</tbody>
</table>
<br><br> 2) Java Assignment Operators <br> Assignment operators are used to assign values to variables. <br><br>
<table class="ws-table-all notranslate table-bordered">
<tbody>
<tr>
<th style="width:30%">Operator</th>
<th style="width:35%">Example</th>
<th style="width:35%">Same As</th>
</tr>
<tr>
<td>=</td>
<td>x = 5</td>
<td>x = 5</td>
</tr>
<tr>
<td>+=</td>
<td>x += 3</td>
<td>x = x + 3</td>
</tr>
<tr>
<td>-=</td>
<td>x -= 3</td>
<td>x = x - 3</td>
</tr>
<tr>
<td>*=</td>
<td>x *= 3</td>
<td>x = x * 3</td>
</tr>
<tr>
<td>/=</td>
<td>x /= 3</td>
<td>x = x / 3</td>
</tr>
<tr>
<td>%=</td>
<td>x %= 3</td>
<td>x = x % 3</td>
</tr>
<tr>
<td>&=</td>
<td>x &= 3</td>
<td>x = x & 3</td>
</tr>
<tr>
<td>|=</td>
<td>x |= 3</td>
<td>x = x | 3</td>
</tr>
<tr>
<td>^=</td>
<td>x ^= 3</td>
<td>x = x ^ 3</td>
</tr>
<tr>
<td>>>=</td>
<td>x >>= 3</td>
<td>x = x >> 3</td>
</tr>
<tr>
<td><<=</td>
<td>x <<= 3</td>
<td>x = x << 3</td>
</tr>
</tbody>
</table><br><br> 3) Java Comparison Operators <br> Comparison operators are used to compare two values (or variables). This is important in programming, because it helps us to find answers and make decisions.
<br><br> The return value of a comparison is either true or false. <br>
<table class="ws-table-all notranslate table-bordered">
<tbody>
<tr>
<th style="width:25%">Operator</th>
<th style="width:45%">Name</th>
<th style="width:30%">Example</th>
</tr>
<tr>
<td>==</td>
<td>Equal to</td>
<td>x == y</td>
</tr>
<tr>
<td>!=</td>
<td>Not equal</td>
<td>x != y</td>
</tr>
<tr>
<td>></td>
<td>Greater than</td>
<td>x > y</td>
</tr>
<tr>
<td><</td>
<td>Less than</td>
<td>x < y</td>
</tr>
<tr>
<td>>=</td>
<td>Greater than or equal to</td>
<td>x >= y</td>
</tr>
<tr>
<td><=</td>
<td>Less than or equal to</td>
<td>x <= y</td>
</tr>
</tbody>
</table>
<br><br>4)Java Logical Operators <br> You can also test for true or false values with logical operators. <br>
<table class="ws-table-all notranslate table-bordered">
<tbody>
<tr>
<th style="width:15%">Operator</th>
<th style="width:20%">Name</th>
<th style="width:45%">Description</th>
<th style="width:20%">Example</th>
</tr>
<tr>
<td>&& </td>
<td>Logical and</td>
<td>Returns true if both statements are true</td>
<td>x < 5 && x < 10</td>
</tr>
<tr>
<td>|| </td>
<td>Logical or</td>
<td>Returns true if one of the statements is true</td>
<td>x < 5 || x < 4</td>
</tr>
<tr>
<td>!</td>
<td>Logical not</td>
<td>Reverse the result, returns false if the result is true</td>
<td>!(x < 5 && x < 10)</td>
</tr>
</tbody>
</table>
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