1Z0-811 Java Language Fundamentals 4

Question 1

Which of the following is true about Java's 'char' data type?

Accepted Answer

It is an unsigned 16-bit integer

Answer

Java's char is an unsigned 16-bit integer representing Unicode characters, with a range of 0 to 65535.

Question 2

What is the output of this code?

int x = 0;
while (x < 5) {
  x += 2;
}
System.out.println(x);

Accepted Answer

6

Answer

x goes 0→2→4→6; when x becomes 6, the condition 6<5 is false, so the loop exits with x=6.

Question 3

Which operator is used for bitwise AND in Java?

Accepted Answer

&

Answer

The single & operator performs bitwise AND on integer operands (and also non-short-circuit boolean AND).

Question 4

What is the scope of a variable declared inside a for-loop initializer?

Accepted Answer

Only the loop block and update expression

Answer

A variable declared in the for-loop initializer (e.g., int i=0) is scoped to the entire for statement including its body, condition, and update.

Question 5

What is the output of the following?

System.out.println("Value: " + 1 + 2);

Accepted Answer

Value: 12

Answer

String concatenation is left-to-right: "Value: "+1 gives "Value: 1", then +2 gives "Value: 12".

(1Z0-811) Oracle Java SE11 Programmer Practice Test