Refrence Types
Reference types in Java include classes, arrays, and interfaces. Unlike primitive types, reference types store addresses (references) to objects rather than the objects themselves.
Classes
- Create complex data structures by grouping variables and methods.
Example:
class Person {
String name;
int age;
}
Person person = new Person(); // `person` reference in stack, `Person` object in heap
Arrays
- Collections of variables of the same type.
Example:
int[] numbers = new int[5]; // `numbers` reference in stack, array in heap
Popcorn Hack
public class Main {
public static void main(String[] args) {
// Create a reference type variable of type String
String myString = "Hello, World!";
// Create a reference type variable of type Array
int[] myArray = new int[] {1, 2, 3, 4, 5};
// Print the values
System.out.println(myString);
// Print the array manually
System.out.print("[");
for (int i = 0; i < myArray.length; i++) {
System.out.print(myArray[i]);
if (i < myArray.length - 1) {
System.out.print(", ");
}
}
System.out.println("]");
}
}
Main.main(null);
Hello, World!
[1, 2, 3, 4, 5]