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This bug is to suggest adding additional, more general conversions "to lambda expression" conversions, e.g., for loops. Currently, Eclipse can convert (via quick fix) an annonymous inner class to a lambda expression, however, it cannot convert a for loop on a collection to an equivalent forEach() call using a lambda expression. Here's an example: List<String> list = Arrays.asList({"Moe", "Larry", "Curly"}); for (String s : list) System.out.println(s); //should be converted to: list.forEach(s -> System.out.println(s)); //or better yet: list.forEach(System.out::println); //and it also should work with streams: list.stream.forEach(System.out::println); Note that NetBeans has some functionality for this, although not perfect. It is based on the following paper: A. Gyori, L. Franklin, D. Dig, and J. Lahoda. Crossing the gap from imperative to functional pro- gramming through refactoring. In Proceedings of the 2013 9th Joint Meeting on Foundations of Software Engineering, pages 543–553. ACM, 2013. http://dl.acm.org/citation.cfm?id=2491461.
This is the bug for the GSoC proposal [1], right? Have you seen bug 431967? I'm moving this bug to JDT/UI (which is where refactorings and quick assists are implemented) to facilitate discussion / coordination. [1] https://wiki.eclipse.org/Google_Summer_of_Code_2015_Ideas#JDT_Core:_More_general_convert_to_lambda_expression_Java_8_refactoring.2Fquick_fixes
(In reply to Stephan Herrmann from comment #1) > This is the bug for the GSoC proposal [1], right? > > Have you seen bug 431967? > > I'm moving this bug to JDT/UI (which is where refactorings and quick assists > are implemented) to facilitate discussion / coordination. > > > [1] > https://wiki.eclipse.org/Google_Summer_of_Code_2015_Ideas#JDT_Core: > _More_general_convert_to_lambda_expression_Java_8_refactoring.2Fquick_fixes Yes, I currently have a student interested in submitting it for his proposal.
(In reply to Stephan Herrmann from comment #1) > This is the bug for the GSoC proposal [1], right? > > Have you seen bug 431967? Ah, no I have not seen that bug! However, I would be hesitant to mark it as a duplicate as the example I give is actually independent of streams. It is certainly related, however.
I just wanted to comment on the status of this bug in respect to the GSoC 2015 project progress. My student's code is in a GitHub repo at http://github.com/mdarefin/Convert-For-Each-Loop-to-Lambda-Expression-Eclipse-Plugin. He developed it as a separate plugin with the intention of integrating it into Eclipse later. The project was not completed during the summer. We broke the tasks down into preconditions and transformation. I would say that the preconditions are almost complete but he did not begin the transformation phase. He does, however, have a full refactoring test suite, which he used for TDD. More information can be found in the issue tracker (completed: https://github.com/mdarefin/Convert-For-Each-Loop-to-Lambda-Expression-Eclipse-Plugin/issues?q=is%3Aissue+is%3Aclosed; pending: https://github.com/mdarefin/Convert-For-Each-Loop-to-Lambda-Expression-Eclipse-Plugin/issues).
Clean-up / Save action or Quickfix for this conversion would be great and seems available in Netbeans as well as in IntelliJ.
