Java Programming

Java program to generate random numbers

Objectives:

  • Write a Java program to to generate random numbers and print the same
  • Write a program to generate random numbers
  • Write a program to generate random numbers in Java

Java Program:

[sourcecode lang="java"]

import java.util.Scanner;
import java.util.Random;

class GenerateRandomNumber
{
public static void main(String[] args)
{
int maxRange;

//create objects
Scanner SC = new Scanner(System.in);
Random rand = new Random();

System.out.print("Please enter maximum range: ");
maxRange=SC.nextInt();

for(int i=1; i<=10; i++)
{
System.out.println(rand.nextInt(maxRange));
}
}
}

[/sourcecode]

Output:

Please enter maximum range: 500
467
61
100
449
68
316
445
224
54
498

Find duplicate characters in string

Objectives:

  • Write a Java program to find duplicate characters in the string and print the duplicate characters
  • Write a program to find duplicate characters in String

Java Program:

[sourcecode lang="java"]
public class DuplicateCharacters {
    public static void main(String args[]) {

        String str = "NITIN";
        int count = 0;

        char input[] = str.toCharArray();
        System.out.println("Duplicate Characters are:");

        for (int i = 0; i &amp;lt; str.length(); i++) {
            for (int j = i + 1; j &amp;lt; str.length(); j++) {
                if (input[i] == input [j]) {
                    System.out.println(input[j]);
                    count++;
                    break;
                }
           }
        }
    }
}
[/sourcecode]

Output:

Duplicate Characters are: N I

Pattern Programs In Java – Pattern 1

Q. Write a Java program to print given pattern.

Pattern 1 :

1
1 2
1 2 3
1 2 3 4
1 2 3 4 5
1 2 3 4 5 6
1 2 3 4 5 6 7

 

Java Program:

[sourcecode language=”java”]

import java.util.Scanner;

public class MainClass

{

public static void main(String[] args)

{

Scanner sc = new Scanner(System.in);

//Taking rows value from the user

System.out.println("How many rows you want in this pattern?");

int rows = sc.nextInt();

System.out.println("Here is your pattern….!!!");

for (int i = 1; i <= rows; i++)

{

for (int j = 1; j <= i; j++)

{

System.out.print(j+" ");

}

System.out.println();

}

//Close the resources

sc.close();

}

}

[/sourcecode]

Java Program to Convert Binary to Decimal

Objectives :

  • Binary to Decimal Conversion
  • Converting Binary to Decimal
  • Write a program to convert binary to decimal
  • Write a program to convert binary number to decimal format
  • Write a program to convert binary to decimal using Scanner class
  • Write a program to convert binary to decimal, take input using Scanner class

Java Program :

[sourcecode lang=”java”]

import java.util.Scanner;

public class BinaryToDecimal {

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print(&quot;Enter binary number: &quot;);
String binary = scanner.nextLine();
int decimal = binaryToDecimal(binary);
System.out.println(&quot;Decimal equivalent of &quot;+ binary +&quot; is &quot;+ decimal);
}

private static int binaryToDecimal(String binary) {
final int base = 2;
int decimal = 0;
for (int i = 0; i &lt; binary.length(); i++) {
if (binary.charAt(i) == ‘0’) {
decimal += 0 * Math.pow(base, binary.length() – i – 1);
} else if (binary.charAt(i) == ‘1’) {
decimal += 1 * Math.pow(base, binary.length() – i – 1);
} else {
System.out.println(&quot;Invalid Binary Number&quot;);
System.out.println(&quot;Binary Number Contains only 0’s or 1’s&quot;);
System.exit(0);
}
}
return decimal;
}
}

[/sourcecode]

Output :
Enter binary number: 1110
Decimal equivalent of 1110 is 14

Java Program to convert Decimal to Binary

Objectives :

  • Decimal to Binary Conversion
  • Converting Decimal to Binary
  • Converting Decimal Number to Binary format
  • Write a program to convert decimal to binary
  • Write a program to convert decimal number to binary format
  • Write a program to convert positive decimal number to binary format
  • Write a program to convert decimal to binary using Scanner class
  • Write a program to convert decimal to binary, take input using Scanner class

 

Java Program to convert Decimal to Binary : 

[sourcecode lang=”java”]
public class DecimalToBinary {

public void toBinary(int number){
int binary[] = new int[25];
int n = 0;
// Convert Decimal to Binary
while(number > 0){
binary[n++] = number%2;
number = number/2;
}
// Print Binary number
for(int i = n-1;i >= 0;i–){
System.out.print(binary[i]);
}
}

public static void main(String[] args){
DecimalToBinary obj = new DecimalToBinary();
obj.toBinary(14);
}
}
[/sourcecode]

Output :

1110

 

Java Program to convert Decimal to Binary using Scanner class :

[sourcecode lang=”java”]

import java.util.Scanner;

public class DecimalToBinary {

public void toBinary(int number){
int binary[] = new int[14];
int n = 0;

// Convert Decimal to Binary
while(number > 0){
binary[n++] = number%2;
number = number/2;
}

// Print Binary Number
for(int i = n-1;i >= 0;i–){
System.out.print(binary[i]);
}
}

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a number: ");
int num= scanner.nextInt();
DecimalToBinary obj = new DecimalToBinary();
obj.toBinary(num);

}
}

[/sourcecode]

Output :

Enter a number: 14

1110

Java Program to find prime number upto N number

Objectives :

  • Write a Java program to find prime number upto N number
  • Write a Java program to print prime number upto N number
  • Write a Java program to find prime number upto N number using Command Line Arguments
  • Write a Java Program to find prime number upto N number via Command Line Arguments
  • Write a Java program to find prime number upto N number using Scanner class

 

Java Program / Code :

Method 1 : Java Program to find Prime Number upto N number using Scanner class

[sourcecode lang=”Java”]

import java.util.Scanner;
class PrimeNumber
{
public static void main(String[] args)
{
int n,p;
Scanner s=new Scanner(System.in);
System.out.println(“Enter number : ”);
n=s.nextInt();
for(int i=2;i<n;i++)
{
p=0;
for(int j=2;j<i;j++)
{
if(i%j==0)
p=1;
}
if(p==0){
System.out.println(i);
}
}
}
}
[/sourcecode]

Method 2 : Java Program to find Prime Number upto N number using Scanner class and writing function to find prime number

Method isPrime() for checking if a number is prime or not

[sourcecode lang=”java”]
public class PrimeNumber{
public boolean isPrime(int num) {
if ( num < 2 ){
return false;
}
for (int i = 2; i <= Math.sqrt(num); i++) {
if ( num % i == 0 ) {
return false;
}
}
return true;
}
}

// Mock Test Class to test above code
import java.util.Scanner;

public class Demo
{
public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);

System.out.println("Please enter a number: ");
int num = scanner.nextInt();

if ( num < 2 ) {
System.out.println("\n There are no Prime Numbers available");
System.exit(0);
}
System.out.println("\n Prime Numbers from 1 to "+ num);
PrimeNumber primeNum = new PrimeNumber();

for (int i = 3; i <= num; i++) {
if ( primeNum.isPrime(i) ) {
System.out.print(", " + i);
}
}
}
}
[/sourcecode]

Method 3 : Java Program to find Prime Number upto N number using Command line input

[sourcecode lang=”Java”]

class PrimeNumber
{
public static void main(String[] args)
{
int n,p;
n=Integer.parseint(args[0]);
for(int i=2;i&lt;n;i++)
{
p=0;
for(int j=2;j&lt;i;j++)
{
if(i%j==0)
p=1;
}
if(p==0){
System.out.println(i);
}
}
}
}
[/sourcecode]

Steps to run above program via command line :

  1. Compilation : C:\JavaPrograms>javac PrimeNumber.java
  2. Interpretation : C:\JavaPrograms>java PrimeNumber 20

Output :

2

3

5

7

11

13

17

19

Program to find Sum of Digits in Java

Objectives :

  • Write a program to compute sum of digits of a given number.
  • Write a program to find sum of digits of a given number.
  • Write a program to calculate sum of digits of a given number.
  • Write a program to compute sum of digits of a given integer number.
  • Write a program to compute sum of digits of a number entered via Command Line.
  • Write a program to compute sum of digits of a given number. Take input from Command Line.
  • Write a program to compute sum of digits of a given number. Take input using Scanner class.

Following is the Java Program to compute Sum of Digits of a given integer number;

Method 1 : Java Program to find Sum of Digits when number is entered from command line

[sourcecode lang=”java”]

class SumOfDigits
{
public static void main(String args[])
{
int n;
int a=0;
int sum=0;

//taking integer number from command line and parsing the same
n=Integer.parseInt(args[0]);

while(n!=0)
{
a=n%10;
n=n/10;
sum=sum+a;
}
System.out.println("Sum of digits: " + sum);
}
}

[/sourcecode]

Steps to run above program via command line :

  1. Compilation : C:\JavaPrograms>javac SumOfDigits.java
  2. Interpretation : C:\JavaPrograms>java SumOfDigits 12345

Output : Sum of digits: 15

Method 2 : Java Program to find Sum of Digits if input is taken using Scanner class

[sourcecode lang=”java”]

import java.util.Scanner;

public class SumOfDigits {
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
int n;
int a=0;
System.out.print("Enter a positive number: ");
n = in.nextInt();

if (n <= 0)
System.out.println("You have entered a negative number.");
else {
int sum = 0;

while (n != 0) {

a=n%10;
n=n/10;
sum=sum+a;
}
System.out.println("Sum of digits: " + sum);
}
}
}

[/sourcecode]

Steps to run above program via command line :

  1. Compilation : C:\JavaPrograms>javac SumOfDigits.java
  2. Interpretation : C:\JavaPrograms>java SumOfDigits 12345

Output :

Trial 1 : With positive number

Enter a positive number: 12345

Sum of digits: 15

Trial 2 : With negative number

Enter a positive number: -12345

You have entered a negative number.

Java continues to be the dominant language – TIOBE

TIOBE programming community index is a measure of popularity of programming languages. TIOBE index for February 2013 says Java is the number one programming language in the world.

The index is based on the calculation from number of search engine results which includes Google, Blogger, Yahoo!, Wikipedia, Baidu, YouTube, Bing and Amazon for queries containing the name of the language, for this TIOBE has their own algorithms.

Following image shows the long term trends for top 10 languages :

TIOBE Trends

TIOBE Trends

I think Java will always be on top.

I Love Java

Source : TIOBE

What coding language do you enjoy working in the most?

Hey friends,

Microsoft has sponsored a Survey titled “What coding language do you enjoy working in the most?”.

Check the poll link and we can show we love Java there for sure.

Here is the link for the survey where you can cast your vote but you need to have Linkedin account to vote : http://linkd.in/ZNSOnC

Being a fan, follower of Java technologies, I have already voted for Java. If you like Java or comfortable with Java technologies as they are very easy but powerful you can also show your love towards Java by voting Java via this survey.

Hello World in different languages

Free Source Code

Free Source Code

Objectives :
* How to write Hello World in Java?
* How to write Hello World in C?
* How to write Hello World in PHP?
* How to write Hello World in C++?
* How to write Hello World in JavaScript?
* How to write Hello World in HTML?
* How to write Hello World in CSS?
* How to write Hello World in COBOL?

Java

[sourcecode language=”java”]
class HelloWorld
{
public static void main(String args[])
{
System.out.println(“Hello World!”);
}
}
[/sourcecode]

C

[sourcecode language=”c”]
#include
#include
void main()
{
clrscr();
printf(“Hello World!”);
getch();
}
[/sourcecode]

C++

[sourcecode language=”cpp”]
#include
#include
void main()
{
clrscr();
cout<getch();
}
[/sourcecode]

CSS

[sourcecode language=”css”]
body:before
{
content: “Hello World”;
}
[/sourcecode]

COBOL

[sourcecode language=”text”]
****************************
IDENTIFICATION DIVISION.
PROGRAM-ID. HELLO ENVIRONMENT DIVISION.
DATA DIVISION.
PROCEDURE DIVISION.
MAIN SECTION.
DISPLAY “Hello World!”
STOP RUN
****************************
[/sourcecode]

HTML

[sourcecode language=”html”]
<html>
<head>
<title>Hello World Example</title>
</head>
<body>
Hello World!
</body>
</html>
[/sourcecode]

JavaScript

[sourcecode language=”javascript”]
document.write("Hello World");
[/sourcecode]

PHP

[sourcecode language=”php”]
<!–?php echo ‘Hello World!’ ?–>
[/sourcecode]

Linux Shell Script

[sourcecode language=”text”]
echo "Hello World !"
[/sourcecode]

Enjoy coding!

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