Builder
Used to write readable and understandable code to set up complex objects.
Whenever you create a class with some members, you pass the values you want them to have to the constructor while creating object. This could get very complex if there are too many members of different types.
Create another (builder) class with all the same members and setters of individual members and return object of the builder class.
Phone newphone = new PhoneBuilder().setOS().setBattery().getPhone()
//getPhone gives the object of Phone type
No need to specify all the values too. Set only the values you want. Rest will have default values.
Children