New static method in interface detected as METHOD_NEW_DEFAULT

[runeflobakk]

I have added a couple of public static methods in an interface, and japicmp detects them as a binary incompatible METHOD_NEW_DEFAULT change. I don't have the knowledge to tell if this indeed is incompatible, but I was a bit surprised, and since the change indicates something to do with default methods, I thought I'd ask if this may be a false positive.

Should adding static methods to an interface be detected as METHOD_NEW_DEFAULT?

If I have not provided enough context here, please just let me know what information you need :)

[WencongLiu]

Hello @runeflobakk , I meet a similar problem with you. The link is ISSUE. The difference is that I set BinaryIncompatible to disabled and SourceIncompatible to enabled.

However, I think adding a default method to an interface shouldn't be source incompatible. Do you have any solution right now?

[siom79]

Hello, you both are right (see here). I will fix this in the next release.

[WencongLiu]

Thanks for your reply! @siom79 Looking forward to the next version.

[WencongLiu]

When will the next version be released, please? @siom79 😄

[siom79]

I have just released 0.17.3. It should be available in Maven central within a few hours.

[Marcono1234]

@siom79, it looks like this issue here was also about whether new static interface methods should be reported as METHOD_NEW_DEFAULT. Is that intended? japicmp 0.17.3 still behaves this way.

For regular classes, adding a static method seems to be reported as METHOD_ADDED_TO_PUBLIC_CLASS. Though there seems to be no corresponding existing type for interfaces yet; METHOD_ADDED_TO_INTERFACE seems to be about abstract interface methods.

[siom79]

@Marcono1234 Yes, you are right. If the method is new an not abstract (e.g. static) it is flagged as METHOD_NEW_DEFAULT. It should rather be flagged METHOD_ADDED_TO_INTERFACE. I need to change that.

[Marcono1234]

It should rather be flagged METHOD_ADDED_TO_INTERFACE

Or would it need a new type? Because METHOD_ADDED_TO_INTERFACE is currently for adding an abstract method, which is not source compatible, while adding a static method is source compatible.

Should maybe METHOD_ADDED_TO_INTERFACE then also be deprecated and be renamed to METHOD_ABSTRACT_ADDED_TO_INTERFACE to be more precise and to match the name of the existing METHOD_ABSTRACT_ADDED_TO_CLASS type?

[siom79]

I have fixed the issue in the latest commit. In this context I have introduced three new incompatiblities:

• METHOD_NEW_STATIC_ADDED_TO_INTERFACE
• METHOD_NON_STATIC_IN_INTERFACE_NOW_STATIC
• METHOD_STATIC_IN_INTERFACE_NO_LONGER_STATIC