If You are interested to learn about the Basic Syntax
In this tutorial, you will learn how to write scala programs. To write scala program you need to install scala on your machine. You must have latest jdk installed on your machine because scala compiler creates .class file which is a byte code. Scala interpreter executes this byte code by using jvm (Java Virtual Machine).
Scala Example: Hello Scala
The following code example is a simple scala program.
object ScalaExample{
def main(args:Array[String]){
println "Hello Scala"
}
} In the above code, we have created an object ScalaExample. It contains a main method and display message using println method.
This file is saved with the name ScalaExample.scala.
Command to compile this code is: scalac ScalaExample.scala
Command to execute the compiled code is: scala ScalaExample
After executing code it yields the following output.
Output:
Hello Scala
You can also use IDE (Integrated Development Environment) for executing scala code. The above example is written using object oriented approach. You can also use functional approach to write code in scala.
Scala Example: Hello Scala
Below is the example by using functional approach.
def scalaExample{
println("Hello Scala")
}
scalaExample // Calling of function Output:
Hello ScalaScala program to print your name.
/*Scala program to print your name*/
object ExPrintName {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
println("My name is Mike!")
}
}
Output
My name is Mike!Scala program to find largest number among two numbers.
/**Scala Program to find largest number among two numbers.*/
object ExFindLargest {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
var number1=20;
var number2=30;
var x = 10;
<strong>if</strong>( number1>number2){
println("Largest number is:" + number1);
}
<strong>else</strong>{
println("Largest number is:" + number2);
}
}
}
Output
Largest number is:30Scala program to find a number is positive, negative or positive.
/**Scala program to find a number is positive<strong>,</strong> negative or positive.*/
object ExCheckNumber {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
/**declare a variable*/
var number= (-100);
<strong>if</strong>(number==0){
println("number is zero");
}
<strong>else</strong> <strong>if</strong>(number>0){
println("number is positive");
}
<strong>else</strong>{
println("number is negative");
}
}
}
Output
number is negativeScala program to declare string variable and print the string.
object ExampleString {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
//declare and assign string variable "text"
val text : <strong>String</strong> = "You are reading SCALA programming language.";
//print the value of string variable "text"
println("Value of text is: " + text);
}
}
Output
Value of text is: You are reading SCALA programming language.Scala program to demonstrate example of multiple variables declarations and assignments.
In this example we will learn, how we can declare and assign multiple variables together?
/*Scala program to demonstrate example of multiple
variables declarations and assignments.*/
object ExampleVarDecAndAssin {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
var (name: <strong>String</strong>, age: Int) = Pair("Mike",21);
//print values
println("Name: "+name);
println("Age: "+age);
//declaration without specifying data type
var (address,mobile)=Pair("New Delhi, India",1234567890);
//print values
println("Address: "+address);
println("Mobile: "+mobile);
}
}
Output
Name: Mike
Age: 21
Address: New Delhi, India
Mobile: 1234567890
Scala program to print numbers from 1 to 100 using for loop.
In this example we will learn, how we can print number from 1 to 100 in Scala using to keyword?
/*Scala program to print numbers from 1 to 100
using for loop.*/
object ExampleForLoop1 {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
var counter: Int=0;
<strong>for</strong>(counter <- 1 to 100)
print(counter + " ");
// to print new line
println();
}
}
Output
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91
92 93 94 95 96 97 98 99 100
Scala program to print numbers from 1 to 100 using for loop with until to determine loop range.
In this example we will learn, how we can print number from 1 to 100 in Scala using until keyword?
/*Scala program to print numbers from 1 to 100
using for loop with until to determine loop range.*/
object ExampleForLoop2 {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
var counter: Int=0;
<strong>for</strong>(counter <- 1 until 101)
print(counter + " ");
// to print new line
println();
}
}
Output
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91
92 93 94 95 96 97 98 99 100
Scala program to demonstrate example of collection list and for loop.
In this program we will learn, how we can declare integers collection and print using for loop?
/*Scala program to demonstrate example of
collection list and for loop.*/
object ExampleForAndCollection {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
//declare an integer
var N: Int=0;
//declare integer list
var numbers = <strong>List</strong>(100,200,300,400);
//to print all numbers using for loop
<strong>for</strong>(N<-numbers){
println(N);
}
}
}
Output
100
200
300
400
Scala program to create a user define function to return largest number among two numbers.
In this example we will learn, how to create a user define function in Scala?
/*Scala program to create a user define function
to return largest number among two numbers.*/
object Example UDF To Get Largest Number {
//function definition
def getLargestNumber(x: Int, y: Int) : Int ={
var largestNumber: Int=0;
<strong>if</strong>(x>y)
largestNumber=x;
<strong>else</strong>
largestNumber=y;
<strong>return</strong> largestNumber;
}
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
var a: Int=10;
var b: Int=20;
//function calling
println("Largest number from "+ a+" and "+ b +" is: "+ getLargestNumber(a,b));
}
}
Output
Largest number from 10 and 20 is: 20
Scala program of array – Declare, print and calculate sum of all elements.
/*Scala program of array - Declare, print
and calculate sum of all elements.*/
object ExampleArray1 {
def main(args: <strong>Array</strong>[<strong>String</strong>]) {
var numbers = <strong>Array</strong>(10,20,30,40);
var N:Int=0;
//print all array elements
println("All array elements: ");
<strong>for</strong> ( N <- numbers ) {
println(N);
}
//calculating SUM of all elements
var sum: Int=0;
<strong>for</strong> ( N <- numbers ) {
sum+=N;
}
println("Sum of all array elements: "+sum);
}
}
Output
All array elements:
10
20
30
40
