Java syntax

Front

What is the correct file extension for a Java program? Options: .java, .js, .py, .txt

Back

.java

Answer explanation

Java files are saved with a .java extension.

Front

Which keyword is used to declare a variable? Options: variable, var, int, let

Back

int

Answer explanation

In Java, 'int' is used for integer variables.

Front

What does the 'public' keyword signify in Java?

Back

It is accessible to all

Answer explanation

public' allows access from any class in the program.

Front

How do you print text to the console in Java?

Back

System.out.println()

Answer explanation

System.out.println() is the correct way to print to the console in Java.

Front

What happens if a local int variable is used without initialization?

Back

It is initialized to 0.

Answer explanation

"Local variables in Java must be explicitly initialized before use, as they do not have default values. Attempting to use an uninitialized local variable results in a compilation error.

Front

What symbol is used to end a Java statement?

Back

;

Answer explanation

Java statements end with a semicolon (;).

Front

What is the correct syntax for a single-line comment?

Back

//

Answer explanation

Single-line comments in Java start with //.

Front

What is the output of System.out.println(5 + "5")?

Back

55

Answer explanation

The + operator concatenates a string and a number, resulting in "55".

Front

How do you declare a constant in Java? Options: constant, final, const, static

Back

final

Answer explanation

final' is used to declare a constant in Java.

Front

Which of these is NOT a valid variable name in Java? myVar, $myVar, 123myVar, _myVar

Back

123myVar

Answer explanation

Variable names cannot start with a digit in Java.