Data Types And Variables - Study Mode

[#81] What would be the output of the following fraction of code? int Integer = 34

char String = 'S'

System.out.print( Integer )

System.out.print( String )

Correct Answer

Does not compile as Integer and String are API class names.

[#82] What is the output of the following program? public class Test{
static int x = 10

public static void main(String[] a){
Test test = new Test( )

Test test1 = new Test( )

test.x += 1

System.out.println( test.x + test1.x )

}
}
Correct Answer

(C) 22

Explanation

Solution: Static variable have a single copy of memory. That means all the objects will share the same memory location. So, if the object test increase the value of x by 1, then object test1 will access that incremented value of x

[#83] What will be output of the following program code? public class Test{
public static void main(String[] a){
short x = 10

x = x*5

System.out.print(x)

}
}
Correct Answer

(C) Compilation Error

Explanation

Solution: lossy conversion from int to short x = x*5

^ 1 error

[#84] Determine output: public class Test{
int i = 34

public static void main(String args[]){
Test t1 = new Test()

Test t2 = new Test()

t1.i = 65

System.out.print(t1.i)

System.out.print(t2.i)

}
}
Correct Answer

(B) 65 34

Explanation

Solution: Instance variable is unique for their object, that means each copy of memory for variable i will be available for each object. So, changing value of i from one object will not affect the value of i accessed by another object. 1. Two objects of the Test class, t1 and t2 , are created using the new keyword. 2. The default value of the instance variable i is 34 as defined in the class Test . 3. The instance variable i of t1 is then set to 65 using t1.i = 65

4. When we print t1.i , it will output 65 . 5. When we print t2.i , it will output 34 . This is because t2 is a separate instance of the Test class, and its i remains the default value of 34 . Therefore, the correct output will be 6534 .

[#85] The following program: public class Test{
static boolean isOK

public static void main(String args[]){
System.out.print(isOK)

}
}
Correct Answer

(B) Prints false

Explanation

Solution: By default, a boolean variable will contain false.