if-else Statement in Java

The if-else Statement in Java

These are condition(branching) blocks. The "if-else" are the basic building blocks of any programming language for branching statements.

if-statement

The "if" is a Single-Selection Statement in itself. 
The conditional statement in Java has the syntax as,

if (condition) statement

The condition must be surrounded by parentheses.

if-else statement

There are two possible paths of execution in the if-else statement. The path is selected upon the basis of the condition expression.

for example,

if( studentGrade>=60)
System.out.println(“Passed”);
else
System.out.println(“Failed”);

if-else ladder

Multiple selection paths are available in the if-else-if ladder. The path will be selected upon the basis of the condition expression.

For example,

public class Demo {
    public static void main(String[] args) {
        int marks=90;
        if(marks>=90)//condition-1
        {
            System.out.println("you have done excellent!!!");
        }else if(marks>=75 && marks<90)//condition-2
        {
            System.out.println("you have done very good!!!");

        }else if(marks>=60 && marks<75)//condition-3
        {
            System.out.println("you have done fair!!!");
        }else if(marks>=50 && marks<60)//condition-4
        {
            System.out.println("you have done satisfactory!!!");
        }
        else//otherwise
        {
            System.out.println("Try again!!!");
        }          
    }
}

Nested if-else Statements

A Java program can test multiple cases by placing if...else statements inside other if...else statements to create nested if...else statements. For example, the following pseudo-code represents a nested if...else that prints A for exam grades greater than or equal to 90, B for grades in the range 80 to 89, C for grades in the range 70 to 79, D for grades in the range 60 to 69 and F for all other grades:

for example:

   

   if ( studentGrade >= 90 )
         System.out.println( "A" );
      else
         if ( studentGrade >= 80 )
            System.out.println( "B" );
         else
            if ( studentGrade >= 70 )
               System.out.println( "C" );
            else
               if ( studentGrade >= 60 )
                  System.out.println( "D" );
               else
                  System.out.println( "F" );

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