I'm a Java programmer, learning to program in Go. So far I really like the language. A LOT more than Java.
But there's one thing I'm a bit confused about. Java has interfaces because classes can inherit only from one class. Since Go allows multiple inheritance, what's the point of interfaces?
分享 Polymorphism
Interfaces enable functions to have a 'placeholder' parameter which can take different structs as an argument. For example, if structs Man, Woman, Child implement interface Human, then a method with the parameter Human can take any of the structs Man, Woman, Child as an argument. Hence, the interface parameter can 'morph' into any struct passed as an argument as long as it implements all functions defined in the interface.
This is important because interfaces are the only way of achieving Polymorphism in Go, since it doesn't have inheritance. So if Man 'extended' Human (by having it as an anonymous field), any method that used Human as an argument, would not be able to take Man as an argument.
My confusion stemmed from the fact that inheritance is also a way of achieving Polymorphism in Java, and I assumed that was the case here as well. I stand corrected!
分享
