Java Class Definitions and Identifier Quiz

What should be the name and extension of the file where the given Java source code should be stored?

public class Test{ public static void main(String[ ] args){ System.out.println("Hello World"); } }

Which of the following is a valid identifier?

Which of the following code displays the area of a circle if the radius is positive?

What is the output of the attached statement if x = 1, y = -1, and z = 1?

Java Class Definition

A Java class definition should be stored in a file with a .java extension, with the file name matching the class name (e.g. Test.java for a class named Test).

Valid Identifiers

Valid identifiers in Java do not include keywords (e.g. class), numbers at the beginning (e.g. 8+9), or special characters (e.g. 9X, $43).

Conditional Statements

The if statement is used to execute code based on a condition.
if (radius = 0) is not a valid condition, as = is an assignment operator, not a comparison operator.
if (radius > 0) is a valid condition to check if the radius is positive.
if (radius .< 0) is not a valid condition, as there is no .< operator in Java.
if (radius .= 0) is not a valid condition, as there is no .= operator in Java.

Logical Operators

The and operator in Java is represented by &&.
The or operator in Java is represented by ||.
x < 0 and z < 0 is not a valid Java statement, use x < 0 && z < 0 instead.
x < 0 and z > 0 is not a valid Java statement, use x < 0 && z > 0 instead.

This quiz tests your knowledge of Java class definitions and valid identifiers. It includes questions about file naming conventions, valid identifier syntax, and more. Test your Java skills now!