Java exam

Question 1

How many primitive data types are there?

Answer 1

8

byte
char
short
int
long
float
double
boolean

Question 2

What format are

byte
char
short
int
long

represented in?

Answer 2

two’s complement format
(left most bit represents the sign for all except char)

Question 3

Will float or double overflow?

Answer 3

No

Question 4

Does Java support a wrapper object for each primitive data type?

Answer 4

Yes ie., Character wrapper object for char primitive data type

Question 5

Can you declare multiple variables of the same data type in the same line in Java?

Answer 5

Yes

ie., double firstDouble, secondDouble;

Question 6

Can you declare multiple variables of different data type in the same line in Java?

Answer 6

No

ie., int myInt, short myShort will give an “identifier expected” error

Question 7

What is an unmodified integer value assumed to be?

Answer 7

A 32 bit int primitive

Question 8

What is a value containing a decimal point assumed to be?

Answer 8

A 64 bit double

Question 9

What is considered a valid char literal?

Answer 9

A single character value in single quotes

Question 10

When does a while statement satisfy compiler’s full initialisation check?

Answer 10

when the if condition is statically known ie.,

while(true) { do something }

it isn’t statically known in scenarios like:
while(v < 1) { do something }