Discussion on: Frequently used design patterns

[Ricardo Costeira]

It really depends on the domain. The ones I used the most until now are:

• Singletons for core entity access (maintaining a database connection or a thread manager, for instance);
• Thread pool for thread managers;
• Observer and iterator (ReactiveX is awesome);
• Facade and repository for data access;
• Adapters for, well, adapting classes to interfaces (used them a lot on Android);
• Builders and factories for objects with many different parameters and versions;
• mvp and mvvm as architectural patterns;
• Strategy and template method because I hate seeing a lot of ifs and switches :)