Java 9 features announced

Re:Java 9 features announced by Tloewald on Monday August 18, 2014 @02:59PM (#8193995)

The purpose of a getter or setter is to abstract the implementation out from the usage. Computed properties (e.g. C#'s ability to replace a concrete property with a virtual property without breaking any code) do this without requiring mindless implementation (boilerplate code) for the common case (a property that is exactly what it seems to be).

As an added bonus, you don't need to write foo.getBar(), you can just write foo.bar and it Just Works, whether foo.bar is a concrete implementation or a computed property.

Look at this blog post for example:

http://java.dzone.com/articles/java-properties-without

The sad thing is the request here is for something more ugly than what is really wanted (this is just automatic getter/setter implementation -- computed properties are better both for developers and consumers of their output.

[ Parent | on HN ]

Re:Java 9 features announced by bassman7755 on Wednesday August 27, 2014 @03:28AM (#8231132)

The problem is that you cant add computed accessor methods to java without breaking code backwards compatibility. This is because a public fields and a public methods have different inheritance semantics - public field access does not trigger polymorphic resolution. Hence auto replacing it with a access method would break any code that relies on the static resolution of the public field (i.e. resolution by referencing type). To fair there probably isnt much code out there that would fall foul of this since there isnt any good reason to write code that relies on public field "hiding" by subclasses, but it would be technically non backwards compatible.

[ Parent | on HN ]