using java and design Patterns at least 4 (2 Behavioral pattern and 2 structural Patterns ) create a sign up and login application with saving the user information to a file and please explain why did you use every Pattern with a coments to help me understand the code

you can choose any of the behavral 2 of them and the structural also 2 of them

for example the state pattren and the composite , adapter, decorator , bridge , command , interator any if them just four of them