Tutorial for Design Patterns https://www.geeksforgeeks.org/java-design-patterns/?ref=gcse_ind

Factory Design Patterns can be produced using Interfaces (implements) or Abstract (extends) classes https://www.baeldung.com/java-factory-pattern

https://www.baeldung.com/java-abstract-factory-pattern

Builder pattern https://www.geeksforgeeks.org/builder-pattern-in-java/ https://www.baeldung.com/java-builder-pattern https://www.digitalocean.com/community/tutorials/builder-design-pattern-in-java

Prototype Design Pattern https://www.geeksforgeeks.org/prototype-design-pattern-in-java/

Singleton https://www.geeksforgeeks.org/singleton-class-java/