8. THE ? OPERATOR

Hi friends what’s up. Hope you are well. Today I will talk about the ? operators.

Java includes a special ternary(three-way) operator that can replace certain types of if-then-else statements. This operator is the ?. It can seem somewhat confusing at first, but the ? can be used very effectively once mastered. The ? has this general form:

         Expression1 ? expression2 : expression3

Here, expression can be any expression that evaluates to a Boolean value. If expression1 is true, then expression2 is evaluated; otherwise, expression3 is evaluated. The result of the ? operation is that of the expression evaluated. Both expression2 and expression3 are required to return the same type , which can’t be void.

Here is an example of the way that the ? is employed:

           ratio = denom == 0 ? 0 : num/denom;

When java evaluates this assignment expression, it first looks at the expression, it first looks at the expression to the left of the question mark. If denom equals zero, then the expression between the question mark and the colon is evaluated and used as the value of the entire ? expression. If denom does not equal zero, then the expression after the colon is evaluated and used for the value of the entire ? expression. The result produced by the ? operator is then assigned to ratio.

Here is a program that demonstrates the ? operator. It uses it to obtain the absolute value of a variable.

public class absolute {

      public static void main(String args[]){

         int i,j;

         

         i = 10;

         j = i<0 ? -i : i;

         System.out.println("Absolute value of " + i +" is " + j);

         

         i = -10;

         j = i<0 ? -i : i;

         System.out.println("Absolute value of " + i +" is " + j);

      }

}

Output:

Absolute value of 10 is 10

Absolute value of -10 is 10

Hope you understand now. Thanks everyone to see this.

Penulis : Mostafij ~ Sebuah blog yang menyediakan berbagai macam informasi

Artikel 8. THE ? OPERATOR ini dipublish oleh Mostafij pada hari Tuesday, April 9, 2013. Semoga artikel ini dapat bermanfaat.Terimakasih atas kunjungan Anda silahkan tinggalkan komentar.sudah ada 0 komentar: di postingan 8. THE ? OPERATOR