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<h2>What is Java?</h2>
<br /><br />
<p>
   Java is a popular programming language, created in
1995.<br />
It is owned by Oracle, and more than 3 billion devices run Java.
<br /><br>
<h2 style="font-weight: 400;">History :</h2><br>
<p>Java programming language was created by James Gosling in 1995. The original idea was to design a language
for the television industry. Gosling worked along with his team also called the Green Team and the project
they worked on was called Greentalk. This project was later named as OAK. The name OAK has its roots to the
oak tree that stood outside Gosling’s office. This name had to be dropped later as it was already a
trademark by Oak Technologies. <br>
<b>So how was the name Java suggested?</b><br> Since the language could no longer be named OAK, Gosling and
his team had to come up with new name. The team considered various names like DNA, RUBY, JAVA, jolt,
dynamic, revolutionary, SILK.But the name had to unique and quite easy to say. The name JAVA occurred in
gosling’s mind while having a cup of coffee at his office.
</p><br>
<h3>It is used for:</h3><br /><br />
<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><br> <Br> <br>
<h2> Why Use Java?</h2>
<br> <br>
<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><br><br><Br>
<h2>Features :</h2><br><br>
<img src="https://cwh-full-next-space.fra1.digitaloceanspaces.com/tutorial/java/features-of-java.png">
<br><br>
<li><b>Object Oriented :</b> In object oriented programming everything is an object rather that function and
logic.</li>
<li><b>Simple:</b> Java is simple to understand, easy to learn and implement.</li>
<li><b>Secured :</b> It is possible to design secured software systems using Java.</li>
<li><b>Platform Independent :</b> Java is write once and run anywhere language, meaning once the code is
written, it can be executed on any software and hardware systems.</li>
<li><b>Portable : </b> Java is not necessarily fixated to a single hardware machine. Once created, java code
can be used on any platform.</li>
<li><b>Architecture Neutral :</b> Java is architecture neutral meaning the size of primitive type is fixed and
does not vary depending upon the type of architecture.</li>
<li><b>Robust :</b> Java emphasizes a lot on error handling, type checking, memory management, etc. This makes
it a robust language.</li>
<li><b>Interpreted :</b> Java converts high-level program statement into Assembly Level Language, thus making
it interpreted.</li>
<li><b>Distributed :</b> Java lets us create distributed applications that can run on multiple computers
simultaneously.</li>
<li><b>Dynamic :</b> Java is designed to adapt to ever evolving systems thus making it dynamic.</li>
<li><b>Multi-thread :</b> multi-threading is an important feature provided by java for creating web
applications.</li>
<li><b>High-performance :</b> Java uses Just-In-Time compiler thus giving us a high performance.</li><br><br>
<h2>Get Started</h2><br><br><br>
<p>It is not necessary to have any prior programming experience.</p>
</p>
<br><br><br><br>
</div>
<div class="notes" id="div2" style="display: none;">
<h2>Installation & Setup</h2><br><br><br>
<h3>Step 1:</h3><br><br>
<p>Before starting the installation processes, it is advisable to check if your PC already has Java installed.
To do this, open the command prompt and type the following:</p><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
C:\Users\yourName>java -version
</code>
</pre><br>
<h3>Output :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
java version "1.8.0_281"
Java(TM) SE Runtime Environment (build 1.8.0_281-b09)
Java HotSpot(TM) 64-Bit Server VM (build 25.281-b09, mixed mode)
</code>
</pre><br><br>
<h3>Step 2:</h3><br>
<p>If your system does not have Java installed, download it from the official website:<br><br><a
href="https://www.oracle.com/java/technologies/downloads/">https://www.oracle.com/java/technologies/downloads/</a>
</p><br>
<h3>Step 3:</h3><br>
<p>Run the downloaded file to install Java on your machine. </p><br><br>
<h3>Step 4:</h3><br>
<li>Go to "System Properties" (Can be found on Control Panel > System and Security > System > Advanced System
Settings)</li>
<li>Click on the "Environment variables" button under the "Advanced" tab</li>
<li>Then, select the "Path" variable in System variables and click on the "Edit" button</li>
<li>Click on the "New" button and add the path where Java is installed, followed by <b>\bin</b>. By default,
Java is installed in
C:\Program Files\Java\jdk-11.0.1 (If nothing else was specified when you installed it). In that case, You
will have to add a new path with: <b>C:\Program Files\Java\jdk-11.0.1\bin</b>
Then, click "OK", and save the settings</li>
<li>At last, open Command Prompt (cmd.exe) and type <b>java --version</b> to see if Java is running on your
machine</li>
<br><br>
<p>Java programs can be written in normal text editor like a notepad or more complicated editors(IDE’s) like
Netbeans, Eclipse or Visual Studio Code.<br>
<br>
For the sake of this tutorial, we will be using Visual Studio Code.
</p><br><br>
</div>
<div class="notes" id="div3" style="display: none;">
<h2>JVM, JRE, JDK</h2><br>
<Bbr>
<img
src="https://th.bing.com/th/id/R.f28367e87c5c5859ab0ac814b76ee4d3?rik=wfI9EaapiJXbUQ&riu=http%3a%2f%2fwww.startertutorials.com%2fcorejava%2fwp-content%2fuploads%2f2015%2f12%2fjvm_jre_jdk.jpg&ehk=OlTfNBiAk6JpWTzymwEaC5QcPMLNSlQ9XgjrwAuOVyU%3d&risl=&pid=ImgRaw&r=0&sres=1&sresct=1"
alt="JVM, JRE, JDK" style="max-width: 38em; height: 500px;"><br><br>
<p><b>A. Java Virtual Machine (JVM):</b><br>The Java Virtual Machine (JVM) is a virtual machine that
provides a runtime environment to execute java bytecode.The java program is converted into java bytecode
which is then translated by the JVM into machine code which can be then understood by the CPU to get the
output. <br><br>
<b>B. Java Runtime Environment (JRE):</b><br> The Java Runtime Environment (JRE) provides java libraries,
the JVM and other files and documents that are needed to run java applications. <br><br>
<b>C. Java Development Kit (JDK):</b><br> The Java Development Kit (JDK) is a superset of JRE and is used
to create java applications. There are three JDK provided by Oracle; Java Enterprise Edition (Java EE),
Java Standard Edition (Java SE), and Java Mobile Edition (Java ME).
</p><br><br>
</div>
<div class="notes" id="div4" style="display: none;">
<h2>Java Syntax</h2><br><br> <br>
<p>It is particularly important to follow the appropriate syntax while writing java code, as we might get
errors for the slightest mistake in our code.</p><br>
<pre class="highlight">
<code class="language-javascript">
public class HelloWorld {
public static void main(String[] args) {
System.out.println("Hello, World!");
}
}
</code>
</pre><br><br>
<h3>Example explained :</h3><br><br>
<p>Every line of code that runs in Java must be inside a <color>Class</color>. In our example, we named the
class <b>Main</b>. A class should always start with an uppercase first letter.</p>
<br>
<p><b>Note:</b> Java is case-sensitive: "MyClass" and "myclass" has different meaning. <br><br>
The name of the java file <b>must match</b> the class name. When saving the file, save it using the class
name and add<b>".java"</b> to the end of the filename. To run the example above on your computer, make sure
that Java is properly installed: Go to the <u>Get Started</u> Chapter for how to install Java. The output
should be:</br>
</p>
<pre class="highlight">
<code class="language-javascript">
Hello, World!
</code>
</pre><br><br>
<p>Any code inside the <color>main()</color> method will be executed. Don't worry about the keywords before
and after main. You will get to know them bit by bit while reading this tutorial.</p><br><br>
<p>For now, just remember that every Java program has a <color>class</color> name which must match the
filename, and that every program must contain the <color>main()</color> method.</p> <br><br>
<p style="font-size: x-large;">System.out.println()</p><br><br>
<p>Inside the <color>main()</color> method, we can use the <color>println()</color> method to print a line of
text to the screen:</p>
<pre class="highlight">
<code class="language-javascript">
public static void main(String[] args) {
System.out.println("Hello, World!");
}
</code>
</pre> <br><br><br>
<P>
<b>Note:</b> The curly braces <color>{}</color> marks the beginning and the end of a block of code.<br><br>
<color>System</color> is a built-in Java class that contains useful members, such as <color>out</color>,
which is short for "output". The <color>println()</color> 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 <color>System, out and println()</color>. 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 (<color>;</color>).
</p>
<br><br><br>
</div>
<div class="notes" id="div5" style="display: none;">
<h2 style="font-size: x-large;">Print Text</h2> <br><br>
<p>You learned from the previous chapter that you can use the <color>println()</color> method to output values
or print text in Java:</p>
<br> <br>
<p>
<h3>Example:</h3>
</p>
<pre class="highlight">
<code class="language-javascript">System.out.println("Hello World!");</code></pre><br><br>
<p>You can add as many <color>println()</color> methods as you want. Note that it will add a new line for each
method:</p> <br><br>
<p>
<h3>Example:</h3>
</p>
<pre class="highlight">
<code class="language-javascript">
System.out.println("Hello World!");<br>
System.out.println("I am learning Java.");<br>
System.out.println("It is awesome!");</code>
</pre>
<br><br>
<h2>Double Quotes</h2><br>
<p>When you are working with text, it must be wrapped inside double quotations marks <color>" "</color>
.<br><Br>If you forget the double quotes, an error occurs:</p>
<pre class="highlight">
<code class="language-javascript">
System.out.println("This sentence will work!");<br>
System.out.println(This sentence will produce an error);<br>
</code>
</pre>
<br><br>
<h2>The Print() Method</h2><br>
<p>There is also a <color> print()</color> method, which is similar to <color>println()</color>.<br>
The only difference is that it does not insert a new line at the end of the output:<br></p>
<br>
<pre class="highlight">
<code class="language-javascript">
System.out.print("Hello World! ");<br>
System.out.print("I will print on the same line.");<br>
</code>
</pre><br>
<p>
Note that we add an extra space (after "Hello World!" in the example above), for better readability.<br>
<br>
In this tutorial, we will only use <color>println()</color> as it makes it easier to read the output of
code.
</p>
<br><br><br>
<h2>Print Numbers</h2><br><br>
<p>You can also use the <color>println()</color> method to print numbers.<br><br>
However, unlike text, we don't put numbers inside double quotes: <br><br>
</p>
<h3>Example :</h3> <br>
<pre class="highlight">
<code class="language-javascript">
System.out.println(3);
System.out.println(358);
System.out.println(50000);
</code>
</pre><br><br>
<p>You can also perform mathematical calculations inside the <color>println()</color> method:</p><br><br>
<h3>Example :</h3><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
System.out.println(2 * 5);
</code>
</pre><br><br>
</div>
<div class="notes" id="div6" style="display: none;">
<h2>Java Comments</h2><br>
<p>Comments can be used to explain Java code, and to make it more readable. It can also be used to <br>
prevent execution when testing alternative code. <br><br></p>
<h3>Single-line Comments</h3><br>
<p>
Single-line comments start with two forward slashes (<color>//</color>). <br><br>
Any text between<color> // </color>and the end of the line is ignored by Java (will not be executed).<br>
<br>
<u>This example uses a single-line comment before a line of code:</u> <br><br>
</p>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">// This is a comment
System.out.println("Hello World");
</code>
</pre><br><br>
<p><u>This example uses a single-line comment at the end of a line of code:</u></p><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
System.out.println("Hello World"); // This is a comment
</code>
</pre><br><br><br>
<h2>Java Multi-line Comments</h2><br>
<p>Multi-line comments start with <color>/*</color> and ends with <color>*/</color>.<br><br>
Any text between <color>/*</color> and <color>/*</color> will be ignored by Java.<br><br>
<u>This example uses a multi-line comment (a comment block) to explain the code:</u>
</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
/* The code below will print the words Hello World <br>
to the screen, and it is amazing */ <br><br>
System.out.println("Hello World");
</code>
</pre><br><br>
</div>
<div class="notes" id="div7" style="display: none;">
<h2>Java Variables</h2><br><br>
<p>Variables are containers that store information that can be manipulated and referenced later by the
programmer within the code. Java variables have a data type associated with them which can tell us about the
size and layout of the variable’s memory.
Variables are containers for storing data values.</p><br><br>
<h3>Syntax :</h3>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
datatype variable = value
</code>
</pre><br><br>
<p>There are three types of variabes in java :</p>
<ol>
<li>Local variable</li>
<li>Instance variable</li>
<li>Class/Static variable</li>
</ol><br>
<h3>A.local variables</h3><br>
<p>A variable that is declared inside the body of the method or constructor is called a local variable. It is
called so because the extent of a local variable lies only within the method or constructor within which it
is created and other methods in the class cannot access it.
Inside the method body, local variable is declared using the static keyword.</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
public class variableType {
public void localVariable() {
String name = "Ben";
int marks = 95;
System.out.println(name + " Scored " + marks + "%.");
}
public static void main(String[] args) {
variableType vt = new variableType();
vt.localVariable();
}
}
</code>
</pre><br><br>
<h3>Output</h3><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Ben Scored 95%.
</code>
</pre><br><br>
<h3>B.Instance Variables:</h3><br>
<p>An instance variable is declared inside the class but outside a method or a constructor. It is similar to a
static variable except that it is declared without using the keyword static. These variables are accessible
by all methods or constructors that are inside the class</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
public class variableType {
public String name = "Ben";
public int marks = 95;
public void instanceVariable() {
System.out.println(name + " Scored " + marks + "%.");
}
public static void main(String[] args) {
variableType vt = new variableType();
vt.instanceVariable();
}
}
</code>
</pre><br><br>
<h3>Output</h3><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Ben Scored 95%.
</code>
</pre><br><br>
<h3>C.Class/Static Variables:</h3><br>
<p>An static variable is declared inside the class but outside a method or a constructor. It is similar to a
instance variable except that it is declared using the keyword static. These variables are accessible by all
methods or constructors that are inside the class.</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
public class variableType {
public static String name;
public static int marks;
public static void main(String[] args) {
name = "Ben";
marks = 95;
System.out.println(name + " Scored " + marks + "%.");
}
}
</code>
</pre><br><br>
<h3>Output</h3><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Ben Scored 95%.
</code>
</pre><br><br>
<p><u>In Java, there are different types of variables, for example:</u></p><br>
<br>
<p>
<ul>
<li>
<color>String</color> - stores text, such as "Hello". String values are surrounded by double quotes</p>
</li>
<li>
<color>int</color> - stores integers (whole numbers), without decimals, such as 123 or -123
</li>
<li>
<color>float</color> - stores floating point numbers, with decimals, such as 19.99 or -19.99
</li>
<li>
<color>char</color> - stores single characters, such as 'a' or 'B'. Char values are surrounded by single
quotes
</li>
<li>
<color>boolean</color> - stores values with two states: true or false
</li>
</ul>
</p>
<h3>Declaring (Creating) Variables</h3><br><br>
<p><u>To create a variable, you must specify the type and assign it a value:</u></p><br>
<h3>
Syntax :
</h3><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
type variableName = value;
</code>
</pre><br><br>
<p>
Where type is one of Java's types (such as <color>int</color> or <color>String</color>), and variableName is
the name of the variable (such as <b>x</b> or <b>name</b>). The <b>equal sign</b> is used to assign values
to the variable.<br>
<br>
To create a variable that should store text, look at the following example: <br><br>
</p>
<h3>Example :</h3><br>
<p>
<br>
Create a variable called name of type String and assign it the value <b>"John"</b>:
</p>
<pre class="highlight">
<code class="language-javascript">
String name = "John";
System.out.println(name);
</code>
</pre><br><br>
<p><u>To create a variable that should store a number, look at the following example:</u><br><br></p>
<h3>Example :</h3><br><br>
<p>Create a variable called <b>myNum</b> of type int and assign it the value <b>15</b>:
</p>
<pre class="highlight">
<code class="language-javascript">
int myNum = 15;
System.out.println(myNum);
</code>
</pre><br><br>
<p><u>You can also declare a variable without assigning the value, and assign the value later:</u></p><br><br>
<h3>
Example :
</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
int myNum;
myNum = 15;
System.out.println(myNum);
</code>
</pre><br><br>
<p><u>Note that if you assign a new value to an existing variable, it will overwrite the previous value:</u>
</p><br><br>
<h3>Example :</h3><br><br>
<p>Change the value of <color>myNum</color> from <color>15</color> to <color>20</color>:</p><br><br>
<h4 style="font-size: larger; font-family: Verdana, Geneva, Tahoma, sans-serif;">
Final Variables
</h4><br><br>
<p>
If you don't want others (or yourself) to overwrite existing values, use the <color>final</color> keyword
(this will declare the variable as "final" or "constant", which means unchangeable and read-only):
</p><br><br>
<h3>
Example :
</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
final int myNum = 15;
myNum = 20; // will generate an error: cannot assign a value to a final variable
</code>
</pre><br><br>
<h4 style="font-size: larger; font-family: Verdana, Geneva, Tahoma, sans-serif;">
Other Types
</h4><br><br>
<p><u>A demonstration of how to declare variables of other types:</u></p><br>
<h3>
Example :
</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
int myNum = 5;
float myFloatNum = 5.99f;
char myLetter = 'D';
boolean myBool = true;
String myText = "Hello";
</code>
</pre><br><br>
</div>
<div class="notes" id="div8" style="display: none;">
<h2>
Display Variables
</h2><br><br>
<p>
The <color>println()</color> method is often used to display variables.<br><br>To combine both text and a
variable, use the <color>+</color> character: <br><br>
</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
String name = "John";
System.out.println("Hello " + name);
</code>
</pre><br><br>
<p>
You can also use the <color>+</color> character to add a variable to another variable:
</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
String firstName = "John ";
String lastName = "Doe";
String fullName = firstName + lastName;
System.out.println(fullName);
</code>
</pre><br><br>
<p>For numeric values, the <color>+</color> character works as a mathematical <u>operator</u> (notice that we
use <color>int </color>(integer) variables here):</p><br><br>
<h3>
Example :
</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
int x = 5;
int y = 6;
System.out.println(x + y); // Print the value of x + y
</code>
</pre><br><br>
<p>
From the example above, you can expect: <br><br>
<ul>
<li>x stores the value 5</li>
<li>y stores the value 6</li>
<li>Then we use the <color>println()</color> method to display the value of x + y, which is <b>11</b></li>
</ul>
</p><br><br>
<h2>Declare Many Variables</h2><br><br>
<p>To declare more than one variable of the <b>same type</b>, you can use a comma-separated list:</p><br><br>
<h3>Example :</h3><br>
<p>
<u>Instead of Writing :</u><br><br>
</p>
<pre class="highlight">
<code class="language-javascript">
int x = 5;
int y = 6;
int z = 50;
System.out.println(x + y + z);
</code>
</pre><br><br>
<p><u>You can simply write:</u></p><br><br>
<pre class="highlight">
<code class="language-javascript">
int x = 5, y = 6, z = 50;
System.out.println(x + y + z);
</code>
</pre><br><br>
<h2 style="font-weight:300;">One Value to Multiple Variables</h2><br><br>
<p>You can also assign the <b>same value</b> to multiple variables in one line:</p><br><br>
<h3>Example :</h3><br><br>
<pre class="highlight">
<code class="language-javascript">
int x, y, z;
x = y = z = 50;
System.out.println(x + y + z);
</code>
</pre><br><br><br>
<h2>Identifiers</h2><br><br>
<p>All Java <b>variables</b> must be <b>identified</b> with <b>unique names</b>. <br><br>
These unique names are called <b>identifiers</b>. <br><br>
Identifiers can be short names (like x and y) or more descriptive names (age, sum, totalVolume). <br><br>
<b>Note:</b> It is recommended to use descriptive names in order to create understandable and maintainable
code: <br><br>
</p>
<pre class="highlight">
<code class="language-javascript">
// Good
int minutesPerHour = 60;
// OK, but not so easy to understand what m actually is
int m = 60;
</code>
</pre><br><br><br>
<p>
The general rules for naming variables are: <br><br>
<li>Names can contain letters, digits, underscores, and dollar signs</li><br>
<li>Names must begin with a letter</li><br>
<li>Names must begin with a letter</li><br>
<li>Names can also begin with $ and _ (but we will not use it in this tutorial)</li><br>
<li>Names are case sensitive ("myVar" and "myvar" are different variables)</li><br>
<li>Reserved words (like Java keywords, such as int or boolean) cannot be used as names</li><br>
</p>
</div>
<div class="notes" id="div9" style="display: none;">
<h2>User Input/Output</h2><br><br>
<h3>Taking Input:</h3><br><br>
<p>There are two ways to take input from the user. But, we mostly use Scanner class to take input from the
user. So, we can learn here about the Scanner class. To use the Scanner class, we need to import the
java.util.Scanner package.</p><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
import java.util.Scanner;
</code>
</pre><br><br>
<p>Now the Scanner class has been imported. We create an object of the Scanner class to use the methods within
it.</p>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Scanner sc = new Scanner(System.in)
</code>
</pre><br><br>
<p>The System.in is passed as a parameter and is used to take input. <br><br>
<b>Note:</b> Your object can be named anything, there is no specific convention to follow. But we normally
name our object sc for easy use and implementation.
</p><br><br>
<h3>There are four ways to create an object of the scanner class. Let us see how we can create Scanner
objects:</h3><br><br>
<h4 style="font-weight: 400;">A. Reading Keyboard input</h4><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Scanner sc = new Scanner(System.in)
</code>
</pre><br><br>
<h4 style="font-weight: 400;">B. Reading String input:</h4><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Scanner sc = new Scanner(String str)
</code>
</pre><br><br>
<h4 style="font-weight: 400;">C. Reading input stream:</h4><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Scanner sc = new Scanner(InputStream input)
</code>
</pre><br><br>
<h4 style="font-weight: 400;">D. Reading File input:</h4><br><br>
<pre class="highlight" style="height: 5em; overflow: hidden;">
<code class="language-javascript">
Scanner sc = new Scanner(File file)
</code>
</pre><br><br>
<h3>So how does a Scanner class work?</h3><br>
<p>The scanner object reads the entered inputs and divides the string into tokens. The tokens are usually
divided based upon whitespaces and newline.</p><br><br>
<h3>Example :</h3><br>
<pre class="highlight" style="height: 9em; overflow: hidden;">
<code class="language-javascript">
Susan
19
78.95
O
</code>
</pre><br><br>
<p>The above input will be divided as “Susan”, “19”, “78.95” and “O”. Then the Scanner object will iterate
over each token and then it will read each token depending upon the type of Scanner object created. <br><br>
Now, we have seen how Scanner object is created, different ways to create it, how it reads input, and how it
works. Let us see different <b> methods to take inputs</b>. <br><br>
<b><u>Below are the methods that belong to the scanner class:</u></b>
</p><br>
<table>
<tr>
<th>Method</th>
<th>Description</th>
</tr>
<tr>
<td>nextLine()</td>
<td>Accepts string value</td>
</tr>
<tr>