code.java

class Context<T extends Property> {
   Path<T> getPath(String dotPath) { … } // foo.bar.foobar
}

class Path<T> { … }

class ResultException {  // ResultException<T> is not allowed
  Path<T> getResolvedPath() { … }
}

try 
  Path<T> path = context.getResult(…);
} catch (ResultException ex) {
  Path<T> resolvedPath = ex.getResolvedPath();
}

explanation.adoc

The idea is to have code to be able to turn a segmented String path (e.g. foo.bar.foobbar) into a Path<T> where T is a generic subtype of a well-known one. If the dot path contains an unresolvable segment I’d like to throw an exception that contains the path that already has been resolved. However it doesn’t seem like I could get the generic type of the Path<T> into the exception and have to resort to the common supertype of T.

I guess I’ll resort to keep the String path that could be resolved in the exception, so that clients can do the following:

try
  Path<T> path = context.getResult(…);
} catch (ResultException ex) {
  Path<T> resolvedPath = context.getPath(ex.getResolvedPath());
}

Slightly more involved but should do the trick.

For reference I went with this approach in the end: spring-projects/spring-data-commons@709bb5c#diff-fd8c8b2042656f92a16069b7ccc3cceeR267