OCA Java SE 8 Mock Exam - OCA Mock Question 7








Question

What is the result of the following program? 

     1:public class Main { 
     2:   public static void addToInt(int x, int amountToAdd) { 
     3:     x = x + amountToAdd; 
     4:   } 
     5:   public static void main(String[] args) { 
     6:     int a = 15; 
     7:     int b = 10; 
     8:     Main.addToInt(a, b); 
     9:     System.out.println(a);   
     10:  } 
     11:}
  1. 10
  2. 15
  3. 25
  4. Compiler error on line 3.
  5. Compiler error on line 8.
  6. None of the above.




Answer



B.

Note

The code runs, so D and E are incorrect.

The value of a is not changed by the addToInt method, because only a copy of the value from a is passed into the parameter x. Therefore, a does not change.

Java always passes parameters by value.

     public class Main { 
        public static void addToInt(int x, int amountToAdd) { 
          x = x + amountToAdd; /*from  w w w.j a  va 2 s. c  o  m*/
        } 
        public static void main(String[] args) { 
          int a = 15; 
          int b = 10; 
          Main.addToInt(a, b); 
          System.out.println(a);   
        } 
     }

The code above generates the following result.