JAVA Control Statements

JAVA Control Statements

The if-else Statement

Java if-else statement works much like the IF statement in any other language. Here, condition is a Boolean expression. If condition is true, then the statement is executed. If condition is false, then the statement is bypassed.

Switch Statement

switch statement is Java’s multiway branch statement. It provides an easy way to

dispatch execution to different parts of your code based on the value of an expression.

As such, it often provides a better alternative than a large series of if-else-if   statements.

 The for Loop

for(initialization; condition; iteration) {

// body

}

 The While Loop

while(condition) {

// body of loop

}

The do-while Loop

do {

// body of loop

} while (condition);

Prorgam # 1

java program finds factorial of a number. Entered number is checked first if its negative then an error message is printed.

public class Factorial

{

   public static void main(String args[])

   {

      int n=10, c, fact = 1;

     

      if ( n < 0 )

         System.out.println("Number should be non-negative.");

      else

      {

         for ( c = 1 ; c <= n ; c++ )

            fact = fact*c;

         System.out.println("Factorial of "+n+" is = "+fact);

      }

   }

}

Output:

 

 

Math Classes

Math class contains all the floating-point functions that are used for geometry and trigonometry, as well as several general-purpose methods. Math defines two double constants: E (approximately 2.72) and PI (approximately 3.14).

The Java Math library function Math.random() generates a double value in the range [0,1). Notice this range does not include the 1.

import java.lang.Math;

public class MathDemo

{

    public static void main(String[] args) 

   {   double num = -4876.1874d;

        double x=10.0,y=20.0;

        int max=15;

 //  print absolute value of num

        System.out.println("\nMath.abs(" + x + ")= " + Math.abs(num));

// print square root value of x

       System.out.println("\nMath.sqrt(" + x + ")= " + Math.sqrt(x));

// print power value of x

       System.out.println("\nMath.pow(" + x + ")= " + Math.pow(x,y));

// print exponential value of x

      System.out.println("\nMath.exp(" + x + ")= " + Math.exp(x));

// print sine value of x in radian

      System.out.println("\nMath.sin(" + x + ")= " + Math.sin(x));

// print maximum value 

      System.out.println("\nMath.max(" + x + ")= " + Math.max(x,y));

// print random value 

      System.out.println("\nMath.random()= " +(Math.random());

    }

}

Output: