Recent Posts by Joe Darcy

As previously reported, the JSR 269 annotation processing APIs in the javax.lang.model and javax.annotation.processing packages are undergoing maintenance review as part of Java SE 9. All the planned changes to the JSR 269 API are in JDK 9 build 164, downloadable as an early access binary. Of note new in build 164 is the annotation type javax.annotation.processing.Generated, meant to be a drop-in replacement for javax.annotation.Generatedsince the latter is not in a...

As has been done previously during Java SE 7 and Java SE 8, the JSR 269 annotation processing API is undergoing a maintenance review (MR) as part of Java SE 9. Most of the API changes are in support of adding modules to the platform, both as a language structure in javax.lang.model.* as well as another interaction point in javax.annotation.processing in the Filer and elsewhere. A small API change was also done to better support repeating annotations. A more detailed summary o...

The slides and video for my JavaOne 2016 talk about JDK 9 Language, Tooling, and Library Features have now been posted. There are many features in the release in addition to modules!

As an addendum to the parting message on coin-dev, one of the most popular candidate coin features not included in JDK 7 was some sort of literal syntax for collections, sets, lists, and/or maps. [1] [2] Fortunately, this functionality is approximated in JDK 9 via Stuart Marks' JEP 269: Convenience Factory Methods for Collections which added factory methods named "of" that return immutable collections to the List, Set, and Map interfaces. I've enjoyed using this feature in my...

Over the last twelve months or so, one of my projects has been fixing and reviewing fixes of javac lint warnings in the JDK 9 code base (varargs,fallthrough,serial,finally,overrides,deprecation,raw and unchecked) and once a warning category is cleared, making new instances of that category a fatal build error. Ultimately, all the warnings in the jdk repository were resolved and -Xlint:all -Werror is now used in the build. Being involved in fixing several thousand warnings,...

As part of milling Project Coin in JDK 9, the try-with-resources statement has been improved. If you already have a resource as a final or effectively final variable, you can use that variable in the try-with-resources statement without declaring a new variable in the try-with-resources statement. For example, given resource declarations like // A final resource final Resource resource1 = new Resource("resource1"); // An effectively final resource ...

The annotation processing API, both the processor-specific portion of the API in javax.annotation.processing and the language modeling portions in javax.lang.model.*, are being updated to support the new language features in Java SE 8. Procedurally, the proposed changes are covered by the second maintenance review of JSR 269: Maintenance Draft Review 2. As summarized on on the maintenance review page, there are three categories of changes from the version of the API shipped...

Back when the javax.lang.model API was being designed as part of JSR 269, while the API was primarily intended for use at compile-time with annotation processing, the expert group also wanted the API to be usable in other contexts as well, including at runtime. JEP 119, javax.lang.model Implementation Backed by Core Reflection, proposed adding such an alternative runtime implementation of javax.lang.model to JDK 8. Such an implementation has recently been pushed as sample code ...

As written up inJEP 182: Policy for Retiring javac -source and -target Options, we're implementing a policy to over time clean up the -source and -target portions of javacs command line: Class files going all the way back to version 45.3 generated by JDK 1.0.2 will continue to be recognized by javac when put on the classpath, etc. The never-documented -target options 1.4.1, 1.4.2, and jsr14 have been removed in JDK 8 (8010179). In JDK 8, source and target options for 1.5 and...