Java Programming Language - Quiz Explanation
Syntax of the Java Programming Language
The answers you selected are indicated below, along with text that explains the correct answers.
1.
A core Java data type that is not derived from any other type and represents a single piece of information is called:
Please select the best answer.
A.
A complex data type
B.
A simple data type
C.
A composite data type
The correct answer is B.
A core Java data type that is not derived from any other type and represents a single piece of information is called a simple data type. A is incorrect because there is no complex Java data type classification. C is incorrect because a composite data type is based on simple types and is used to represent more complex information.
2.
What is a special construct in Java that allows you to store a list of items of the same data type?
Please select the best answer.
A.
A string
B.
A literal
C.
An array
The correct answer is C.
An array is a special construct in Java that allows you to store a list of items of the same data type. A is incorrect because although you can think of a string as storing a list of characters, strings aren't really handled that way in Java. B is incorrect because a literal is a program data element that is constant, and does not have anything specifically to do with lists of data.
3.
Java arrays are known as zero-based arrays because:
Please select the best answer.
A.
Their indexes always begin with zero.
B.
They always start out with zero elements.
C.
They are always terminated with the number zero.
The correct answer is A.
Java arrays are known as zero-based arrays because their indexes always begin with zero. B is incorrect because arrays can be initialized upon being created, in which case they start out with meaningful data. C is incorrect because there is no special termination data for arrays in Java.
4.
What kind of operation does the modulus operator (%) perform?
Please select the best answer.
A.
It converts from decimal to percent.
B.
It determines the remainder of a division.
C.
It determines the average of two numbers.
The correct answer is B.
The modulus operator (%) determines the remainder of a division. There is no Java operator to convert from decimal to percent, and there is no Java operator for determining the average of two numbers.
5.
Determine the value of x after execution of the following statement:
int x = 24 / 8 + 7 * 7 - 5 + 4;
Please select the best answer.
A.
69
B.
51
C.
43
The correct answer is B.
In this expression, first the multiplications and divisions are performed from left to right and then the additions and subtractions are performed from left to right. The expression is evaluated in the following steps:
24 / 8 + 7 * 7 - 5 + 4
3 + 7 * 7 - 5 + 4
3 + 49 - 5 + 4
52 - 5 + 4
47 + 4
51