Java 1

What is Java primarily used for?

• Creating music

• Mobile apps, web apps, and games

• Photo editing

• 3D modeling

Answer explanation

Java is primarily used for developing mobile apps, web apps, and games. It is a versatile programming language for creating software applications across various platforms.

Which of these is a valid Java data type?

• character

• image

• Booleans

• sound

Answer explanation

The valid Java data type among the choices is Booleans. Booleans represent true or false values in Java programming.

What does OOP stand for?

• Oriented Optional Programming

• Optional Object Programming

• Object Oriented Programming

• Only Object Programming

Answer explanation

OOP stands for Object Oriented Programming, making it the correct choice among the options provided.

Which method is used to print text in Java?

• console.log()

• printText()

• System.out.println()

• document.write()

Answer explanation

The correct method to print text in Java is System.out.println().

What is the correct way to declare a variable in Java?

• const value;

• var name;

• int age;

• let number;

Answer explanation

The correct way to declare a variable in Java is by using 'int' followed by the variable name, as shown in 'int age;'.

Which of these is a Java loop structure?

• loop

• repeat-until

• for

• do-while

Answer explanation

The correct Java loop structures are 'for' and 'do-while'. These loops are commonly used for iterating through code blocks based on certain conditions.

What is encapsulation in Java?

• A type of data structure

• Wrapping data and code together

• A version of Java

• A security mechanism

Answer explanation

Encapsulation in Java refers to wrapping data and code together, ensuring data hiding and access control. It is not a type of data structure, version of Java, or a security mechanism.

Which of these is not a Java modifier?

• static

• dynamic

• public

• protected

Answer explanation

The correct choice is 'dynamic' as it is not a Java modifier. 'static', 'public', and 'protected' are all valid Java modifiers.

What does the 'new' keyword do in Java?

• Creates a new object

• Updates a method

• Starts a new thread

• Declares a static variable

Answer explanation

The 'new' keyword in Java is used to create a new object, making it the correct choice among the options provided.

Which of these is a Java collection class?

• ListArray

• Array

• ArrayList

• CollectionList

Answer explanation

The correct choice is ArrayList as it is a Java collection class, while the other options are not valid Java collection classes.