/*
Java break statement example.
This example shows how to use java break statement to terminate the loop.
*/
public class JavaBreakExample {
public static void main(String[] args) {
/*
* break statement is used to terminate the loop in java. The following example
* breaks the loop if the array element is equal to true.
*
* After break statement is executed, the control goes to the statement
* immediately after the loop containing break statement.
*/
int intArray[] = new int[]{1,2,3,4,5};
System.out.println("Elements less than 3 are : ");
for(int i=0; i < intArray.length ; i ++)
{
if(intArray[i] == 3)
break;
else
System.out.println(intArray[i]);
}
}
}
/*
Output would be
Elements less than 3 are :
1
2
*/
Java break statement
Java break statement with label
/*
Java break statement with label example.
This example shows how to use java break statement to terminate the labeled loop.
The following example uses break to terminate the labeled loop while searching two
dimensional int array.
*/
public class JavaBreakWithLableExample {
public static void main(String[] args) {
int[][] intArray = new int[][]{{1,2,3,4,5},{10,20,30,40,50}};
boolean blnFound = false;
System.out.println("Searching 30 in two dimensional int array..");
Outer:
for(int intOuter=0; intOuter < intArray.length ; intOuter++)
{
Inner:
for(int intInner=0; intInner < intArray[intOuter].length; intInner++)
{
if(intArray[intOuter][intInner] == 30)
{
blnFound = true;
break Outer;
}
}
}
if(blnFound == true)
System.out.println("30 found in the array");
else
System.out.println("30 not found in the array");
}
}
/*
Output would be
Searching 30 in two dimensional int array..
30 found in the array
*/
Swap Numbers Without Using Third Variable
/*
Swap Numbers Without Using Third Variable Java Example
This Swap Numbers Java Example shows how to
swap value of two numbers without using third variable using java.
*/
public class SwapElementsWithoutThirdVariableExample {
public static void main(String[] args) {
int num1 = 10;
int num2 = 20;
System.out.println("Before Swapping");
System.out.println("Value of num1 is :" + num1);
System.out.println("Value of num2 is :" +num2);
//add both the numbers and assign it to first
num1 = num1 + num2;
num2 = num1 - num2;
num1 = num1 - num2;
System.out.println("Before Swapping");
System.out.println("Value of num1 is :" + num1);
System.out.println("Value of num2 is :" +num2);
}
}
/*
Output of Swap Numbers Without Using Third Variable example would be
Before Swapping
Value of num1 is :10
Value of num2 is :20
Before Swapping
Value of num1 is :20
Value of num2 is :10
*/
Swap Numbers Java Example
/*
Swap Numbers Java Example
This Swap Numbers Java Example shows how to
swap value of two numbers using java.
*/
public class SwapElementsExample {
public static void main(String[] args) {
int num1 = 10;
int num2 = 20;
System.out.println("Before Swapping");
System.out.println("Value of num1 is :" + num1);
System.out.println("Value of num2 is :" +num2);
//swap the value
swap(num1, num2);
}
private static void swap(int num1, int num2) {
int temp = num1;
num1 = num2;
num2 = temp;
System.out.println("After Swapping");
System.out.println("Value of num1 is :" + num1);
System.out.println("Value of num2 is :" +num2);
}
}
/*
Output of Swap Numbers example would be
Before Swapping
Value of num1 is :10
Value of num2 is :20
After Swapping
Value of num1 is :20
Value of num2 is :10
*/
Reverse Number using Java
/*
Reverse Number using Java
This Java Reverse Number Example shows how to reverse a given number.
*/
public class ReverseNumber {
public static void main(String[] args) {
//original number
int number = 1234;
int reversedNumber = 0;
int temp = 0;
while(number > 0){
//use modulus operator to strip off the last digit
temp = number%10;
//create the reversed number
reversedNumber = reversedNumber * 10 + temp;
number = number/10;
}
//output the reversed number
System.out.println("Reversed Number is: " + reversedNumber);
}
}
/*
Output of this Number Reverse program would be
Reversed Number is: 4321
*/
Java Interface example
/*
Java Interface example.
This Java Interface example describes how interface is defined and
being used in Java language.
Syntax of defining java interface is,
<modifier> interface <interface-name>{
//members and methods()
}
*/
//declare an interface
interface IntExample{
/*
Syntax to declare method in java interface is,
<modifier> <return-type> methodName(<optional-parameters>);
IMPORTANT : Methods declared in the interface are implicitly public and abstract.
*/
public void sayHello();
}
}
/*
Classes are extended while interfaces are implemented.
To implement an interface use implements keyword.
IMPORTANT : A class can extend only one other class, while it
can implement n number of interfaces.
*/
public class JavaInterfaceExample implements IntExample{
/*
We have to define the method declared in implemented interface,
or else we have to declare the implementing class as abstract class.
*/
public void sayHello(){
System.out.println("Hello Visitor !");
}
public static void main(String args[]){
//create object of the class
JavaInterfaceExample javaInterfaceExample = new JavaInterfaceExample();
//invoke sayHello(), declared in IntExample interface.
javaInterfaceExample.sayHello();
}
}
/*
OUTPUT of the above given Java Interface example would be :
Hello Visitor !
*/
Java Factorial Using Recursion
/*
Java Factorial Using Recursion Example
This Java example shows how to generate factorial of a given number
using recursive function.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class JavaFactorialUsingRecursion {
public static void main(String args[]) throws NumberFormatException, IOException{
System.out.println("Enter the number: ");
//get input from the user
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
int a = Integer.parseInt(br.readLine());
//call the recursive function to generate factorial
int result= fact(a);
System.out.println("Factorial of the number is: " + result);
}
static int fact(int b)
{
if(b <= 1)
//if the number is 1 then return 1
return 1;
else
//else call the same function with the value - 1
return b * fact(b-1);
}
}
/*
Output of this Java example would be
Enter the number:
5
Factorial of the number is: 120
*/
Java Factorial Example
/*
Java Factorial Example
This Java Factorial Example shows how to calculate factorial of
a given number using Java.
*/
public class NumberFactorial {
public static void main(String[] args) {
int number = 5;
/*
* Factorial of any number is !n.
* For example, factorial of 4 is 4*3*2*1.
*/
int factorial = number;
for(int i =(number - 1); i > 1; i--)
{
factorial = factorial * i;
}
System.out.println("Factorial of a number is " + factorial);
}
}
/*
Output of the Factorial program would be
Factorial of a number is 120
*/
Java Class example
/*
Java Class example.
This Java class example describes how class is defined and being used
in Java language.
Syntax of defining java class is,
<modifier> class <class-name>{
// members and methods
}
*/
public class JavaClassExample{
/*
Syntax of defining memebers of the java class is,
<modifier> type <name>;
*/
private String name;
/*
Syntax of defining methods of the java class is,
<modifier> <return-type> methodName(<optional-parameter-list>) <exception-list>{
...
}
*/
public void setName(String n){
//set passed parameter as name
name = n;
}
public String getName(){
//return the set name
return name;
}
//main method will be called first when program is executed
public static void main(String args[]){
/*
Syntax of java object creation is,
<class-name> object-name = new <class-constructor>;
*/
JavaClassExample javaClassExample = new JavaClassExample();
//set name member of this object
javaClassExample.setName("Visitor");
// print the name
System.out.println("Hello " + javaClassExample.getName());
}
}
/*
OUTPUT of the above given Java Class Example would be :
Hello Visitor
*/
Hello World java
/*
Java Hello World example.
*/
public class HelloWorldExample{
public static void main(String args[]){
/*
Use System.out.println() to print on console.
*/
System.out.println("Hello World !");
}
}
/*
OUTPUT of the above given Java Hello World Example would be :
Hello World !
*/
Find Largest and Smallest Number in an Array
/*
Find Largest and Smallest Number in an Array Example
This Java Example shows how to find largest and smallest number in an
array.
*/
public class FindLargestSmallestNumber {
public static void main(String[] args) {
//array of 10 numbers
int numbers[] = new int[]{32,43,53,54,32,65,63,98,43,23};
//assign first element of an array to largest and smallest
int smallest = numbers[0];
int largetst = numbers[0];
for(int i=1; i< numbers.length; i++)
{
if(numbers[i] > largetst)
largetst = numbers[i];
else if (numbers[i] < smallest)
smallest = numbers[i];
}
System.out.println("Largest Number is : " + largetst);
System.out.println("Smallest Number is : " + smallest);
}
}
/*
Output of this program would be
Largest Number is : 98
Smallest Number is : 23
*/
Odd Number Java
/*
Even Odd Number Example
This Java Even Odd Number Example shows how to check if the given
number is even or odd.
*/
public class FindEvenOrOddNumber {
public static void main(String[] args) {
//create an array of 10 numbers
int[] numbers = new int[]{1,2,3,4,5,6,7,8,9,10};
for(int i=0; i < numbers.length; i++){
/*
* use modulus operator to check if the number is even or odd.
* If we divide any number by 2 and reminder is 0 then the number is
* even, otherwise it is odd.
*/
if(numbers[i]%2 == 0)
System.out.println(numbers[i] + " is even number.");
else
System.out.println(numbers[i] + " is odd number.");
}
}
}
/*
Output of the program would be
1 is odd number.
2 is even number.
3 is odd number.
4 is even number.
5 is odd number.
6 is even number.
7 is odd number.
8 is even number.
9 is odd number.
10 is even number.
*/
Calculate Rectangle Perimeter using Java
/*
Calculate Rectangle Perimeter using Java Example
This Calculate Rectangle Perimeter using Java Example shows how to calculate
perimeter of Rectangle using it's length and width.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class CalculateRectPerimeter {
public static void main(String[] args) {
int width = 0;
int length = 0;
try
{
//read the length from console
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please enter length of a rectangle");
length = Integer.parseInt(br.readLine());
//read the width from console
System.out.println("Please enter width of a rectangle");
width = Integer.parseInt(br.readLine());
}
//if invalid value was entered
catch(NumberFormatException ne)
{
System.out.println("Invalid value" + ne);
System.exit(0);
}
catch(IOException ioe)
{
System.out.println("IO Error :" + ioe);
System.exit(0);
}
/*
* Perimeter of a rectangle is
* 2 * (length + width)
*/
int perimeter = 2 * (length + width);
System.out.println("Perimeter of a rectangle is " + perimeter);
}
}
/*
Output of Calculate Rectangle Perimeter using Java Example would be
Please enter length of a rectangle
10
Please enter width of a rectangle
15
Perimeter of a rectangle is 50
*/
Calculate Rectangle Area using Java
/*
Calculate Rectangle Area using Java Example
This Calculate Rectangle Area using Java Example shows how to calculate
area of Rectangle using it's length and width.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class CalculateRectArea {
public static void main(String[] args) {
int width = 0;
int length = 0;
try
{
//read the length from console
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please enter length of a rectangle");
length = Integer.parseInt(br.readLine());
//read the width from console
System.out.println("Please enter width of a rectangle");
width = Integer.parseInt(br.readLine());
}
//if invalid value was entered
catch(NumberFormatException ne)
{
System.out.println("Invalid value" + ne);
System.exit(0);
}
catch(IOException ioe)
{
System.out.println("IO Error :" + ioe);
System.exit(0);
}
/*
* Area of a rectangle is
* length * width
*/
int area = length * width;
System.out.println("Area of a rectangle is " + area);
}
}
/*
Output of Calculate Rectangle Area using Java Example would be
Please enter length of a rectangle
10
Please enter width of a rectangle
15
Area of a rectangle is 150
*/
Calculate Circle Perimeter using Java
/*
Calculate Circle Perimeter using Java Example
This Calculate Circle Perimeter using Java Example shows how to calculate
Perimeter of circle using it's radius.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class CalculateCirclePerimeterExample {
public static void main(String[] args) {
int radius = 0;
System.out.println("Please enter radius of a circle");
try
{
//get the radius from console
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
radius = Integer.parseInt(br.readLine());
}
//if invalid value was entered
catch(NumberFormatException ne)
{
System.out.println("Invalid radius value" + ne);
System.exit(0);
}
catch(IOException ioe)
{
System.out.println("IO Error :" + ioe);
System.exit(0);
}
/*
* Perimeter of a circle is
* 2 * pi * r
* where r is a radius of a circle.
*/
//NOTE : use Math.PI constant to get value of pi
double perimeter = 2 * Math.PI * radius;
System.out.println("Perimeter of a circle is " + perimeter);
}
}
/*
Output of Calculate Circle Perimeter using Java Example would be
Please enter radius of a circle
19
Perimeter of a circle is 119.38052083641213
*/
Calculate Circle Area using Java
/*
Calculate Circle Area using Java Example
This Calculate Circle Area using Java Example shows how to calculate
area of circle using it's radius.
*/
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class CalculateCircleAreaExample {
public static void main(String[] args) {
int radius = 0;
System.out.println("Please enter radius of a circle");
try
{
//get the radius from console
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
radius = Integer.parseInt(br.readLine());
}
//if invalid value was entered
catch(NumberFormatException ne)
{
System.out.println("Invalid radius value" + ne);
System.exit(0);
}
catch(IOException ioe)
{
System.out.println("IO Error :" + ioe);
System.exit(0);
}
/*
* Area of a circle is
* pi * r * r
* where r is a radius of a circle.
*/
//NOTE : use Math.PI constant to get value of pi
double area = Math.PI * radius * radius;
System.out.println("Area of a circle is " + area);
}
}
/*
Output of Calculate Circle Area using Java Example would be
Please enter radius of a circle
19
Area of a circle is 1134.1149479459152
*/
