Java Values and Data Types Quiz

What are the primitive data types in Java?

• string, array, object, null, undefined

• integer, decimal, boolean, character, void

• int, long, float, double, boolean, char, and byte

• true, false, null, undefined, NaN

Explain the difference between int and double data types in Java.

• int and double are the same data type in Java.

• int stores whole numbers, while double stores decimal numbers.

• int is used for text data, while double is used for numerical data.

• int stores decimal numbers, while double stores whole numbers.

What are the numeric data types in Java?

• byte, short, int, long, float, and double

• float, char, boolean

• int, double, boolean

• string, boolean, char

How is a char data type represented in Java?

• 'char'

• boolean

• double

• int

What is the boolean data type used for in Java?

• To represent true or false values

• To represent numbers

• To store text

• To perform mathematical operations

Explain the concept of true and false in boolean data type in Java.

• The boolean data type in Java represents true or false values.

• Boolean data type in Java is used for storing characters and symbols.

• In Java, true is represented as 0 and false is represented as 1.

• The boolean data type in Java represents numbers and strings.

What is the string data type in Java?

• Integer

• Boolean

• String

• Double

How do you declare and initialize a string variable in Java?

• int variableName = 'initial value';

• String variableName = initial value;

• String variableName = new String('initial value');

• String variableName = "initial value";

What are the different methods available for string manipulation in Java?

• add(), remove(), concat(), indexOf()

• split(), join(), reverse(), isEmpty()

• substring(), length(), charAt(), toUpperCase(), toLowerCase(), trim(), replace()

• toUpperCaseFirstLetter(), toUpperCaseLastLetter(), toUpperCaseVowels(), toUpperCaseConsonants()

Explain the concept of string immutability in Java.

• A string can be modified multiple times after creation

• Once a string object is created, it cannot be changed or modified.

• String immutability means that strings are always null

• String immutability only applies to certain data types