Bug 578006

Description Jens Lideström 2021-12-31 05:55:36 EST

It would make some parts of the databinding framework more convenient to use if lambda expressions could be used directly for IConverters.

### Example

var s = new UpdateValueStrategy<Integer, String>();

// Like this:
s.setConverter(i -> "int: " + i);

// Instead of this:
s.setConverter(IConverter.create(i -> "int: " + i));

### Implementation

This can be achieved by providing default implementations for the methods IConverter.getFromType and IConverter.getToType. The only remaining unimplemented method would be IConverter.convert, which would make it possible to implement a converter with a lambda.

### Disadvantages

To do this the API annotations @noextend and @noimplement would need to be removed from IConverter, opening up the type for direct implementation by clients. This makes it a little harder to make  additions to the IConverter in the future. This seem to be a small problem however, which is more than enough balanced by the benefits of the change. This is because modern Java versions have the default method construct, and also that IConverter is a stable interface which is unlikely to be changed in the future.