Java data types with examples

Stella 71 Published: 11/17/2024

Java data types with examples

Here are the basic data types in Java with examples:

1. Primitive Data Types

Java has eight primitive data types, which are:

int: an integer value (e.g., 123) byte: a byte value (-128 to 127) short: a short integer value (-32768 to 32767)

long: a long integer value (-9,223,372,036,854,775,807 to 9,223,372,036,854,775,807) float: a floating-point number (e.g., 123.45f) double: a double-precision floating-point number boolean: a true or false value char: a single character (e.g., 'a' or 'n')

Example:

int age = 30;

byte score = 80;


short height = 175;


long population = 1000000L; // note the L suffix for long


float grade = 3.5f;


double pi = 3.14159;


boolean isAdmin = true;


char letter = 'A';

2. Non-Primitive Data Types

Java also has several non-primitive data types:

String: a sequence of characters (e.g., "hello") Array: a collection of values of the same type (e.g., int[] scores) Object: a reference to any object Wrapper Class (e.g., Integer, Double, Boolean): a class that wraps around a primitive value

Example:

String name = "John";

int[] scores = {90, 80, 70};


Object obj = new Object();


Integer ageInt = Integer.valueOf(30);


Double scoreDouble = Double.valueOf(3.5);


Boolean isAdminBool = Boolean.TRUE;

Note: In Java, the null value is equivalent to the absence of any object reference.

Additional tips:

Use meaningful variable names to make your code more readable. Use constants instead of magic numbers (e.g., use final int MAX_SCORE = 100; instead of int score = 100;) Use enum types when you need a set of named values (e.g., public enum Days { MONDAY, TUESDAY, WEDNESDAY };) Use class types to create custom data types (e.g., public class Person { public int age; public String name; })

I hope this helps!

Java data types with examples

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