I'd welcome a separate discussion about a backward compatibility contract, but clearly we have to contrast the "technically Java 8 is supported" with "realistically, any project that uses standard up-to-date tools can't use Java 8 by the end of 2023". We support _end users_ to the extreme, as so many huge enterprise apps built with GWT end up in situations with ancient PCs running out-of-date browsers, but we may need to consider Java or jakarta versioning to be different, as those face the developers and deployments.
If we assume that support Java 8 is required, we have roughly two options: * Support it only on the server, but not dev mode. GWT can migrate to Java 11/17/etc but be sure that gwt-servlet.jar and the like are only built with with Java 8 bytecode. This add a small amount of complexity to the build, and limits use of new features, but unblocks the compiler and dev mode from supporting newer versions of Jetty, JDT, etc. Jetty 9 is EOL, and 10 and 11 require Java 11. In turn, this is going to cut us off from HtmlUnit updates before much longer. Any recent JDT also requires Java 11, so we're cut off from records, multi-line strings, pattern matching, etc. Closure-compiler has also dropped Java 8 support, as another example (from Google, which famously requires Java 7 support for so long). * Support two long term releases, whereas we only support "the latest release" today, and don't backport fixes. This imposes very little burden today, as most commits will go in both branches, but costs will go up as time goes on, especially if we expect to make it until _at least_ 2030 with a long running 2.11 branch or whatever. It wouldn't quite double our current review/testing/release overhead, but I suspect it will be close to that in five years. Either way we're starving for code reviewers and testers today - reported bugs may get fixes, but those fixes are not being tested and critical reviews are not being done. So I put this to teams that will require Java 8 in 2023 and beyond: additional support of some kind or another is required to maintain your use case. Do you need to deploy to Java 8 environments, or do you need to do all development in Java 8 as well? Are you able to coordinate with us to help make your use case a reality? On Monday, January 2, 2023 at 12:49:36 PM UTC-6 eliasbala...@gmail.com wrote: > My 2 cents: > > We also have quite a few projects here based on GWT, still running DevMode > on Java 1.8 I am afraid. > Like everyone else sharing the same fate, we are struggling to upgrade to > Java 11 which seems to be the next sensible move. > Yet, the world is being indirectly and inevitably forced to embrace the > transformation challenge, as relevant tools and integrations have already > switched to Java 11 (e.g. Jenkins). > > In our experience, when using DevMode, it is best to run simpler variants > of the actual UI apps, or keep them as simple as possible so that they can > still run on Jetty even with an altered classpath. > > On Monday, 2 January 2023 at 13:10:59 UTC hthdjeu...@googlemail.com wrote: > >> We have a project here that uses GWT for all its web UI and is still >> running Java 1.8. The SAP JVM 8 will be supported at least until 2030. >> According to >> https://newrelic.com/resources/report/2022-state-of-java-ecosystem in >> April 2022 still close to half of the projects (46%) were using Java 1.8. >> We have made some efforts to move to 11 and 17 and succeeded to the degree >> that we have the build pipelines running for those two new LTS versions >> using their respective JDKs to compile, have our Docker images ready and >> can run the solution with both these new Java LTS releases. But this took a >> few months, and I find it very likely that from the 46% of the projects not >> all have the resources to invest into the migration. If only half of them >> do, we're still at those ~25% that Colin already sampled from the responses >> on this thread who will continue to use 1.8 for some time to come. >> >> Still, we're not yet decided on making the move. Even when using the >> sapmachine.io flavors of the new JDKs we will lose some beloved features >> we get from SAP JVM 8, among them a really neat profiler that integrates >> nicely with Eclipse, as well as reversible on-the-fly debugging. The only >> immediate incentive for a migration to 17 could be the performance >> improvements we measure (depending on the type of workload an average >> improvement by 10-20%), whereas language features or the new GCs (which >> frankly were a bit disappointing for our parallelizing workloads) are not >> in such high demand in our case. >> >> Ironically, since we live off a fork of the GWT project to already >> incorporate two PRs we've made into our production, Java 1.8 is still >> required to run the GWT build... >> >> The compatibility issues raised here are of course all very valid. Some >> things seem reasonably easy to deal with (see, e.g., >> https://github.com/gwtproject/gwt/pull/9791). Other cases, some of which >> discussed here, too, such as potentially giving up the classic DevMode in a >> future release, and removing support for old IE versions in the current >> 2.10 release, may break existing projects for sure. The same applies for >> potential changes that don't deal "only" with bumping versions of >> dependencies but that try to improve aspects of GWT at the expense of what >> I would call minor compatibility glitches (see the discussion here: >> https://github.com/gwtproject/gwt/pull/9779). >> >> With some of these things I find it a problem that GWT doesn't seem to >> have a clearly defined "set of contracts" based on which "backward >> compatibility" could be defined. There are, e.g., things that for technical >> reasons have been made "protected" in non-final classes or public in other >> classes that probably shouldn't count as part of the "GWT contract." Yet, >> with enough projects out there in the wild there may be a few that exploit >> exactly those elements and hence would break in case of changes in those >> areas. Disallowing any change in any of these areas, however, may box GWT >> in this compatibility trap forever. And having to postponse such changes to >> releases that will break massively in other areas and hence may cause >> disruption and lack of adoption for a fair share of GWT-based projects >> doesn't seem ideal to me, either. >> >> Maybe we should take away from these challenges that it would be a good >> thing going forward to be more explicit abut which parts of GWT are >> contract and which ones are not; and those latter ones we then should be >> able to change incompatibly without worrying about adopters. >> On Thursday, August 4, 2022 at 5:05:45 AM UTC+2 nilo...@gmail.com wrote: >> >>> >>> >>> If there’s one thing that GWT has tried to be consistent about, it is >>> retaining support for technologies past their “best by” dates. This is a >>> sore point from time to time, as it makes the tooling feel dated even right >>> after a release, but it has some specific advantages with regards to >>> enabling projects that are otherwise in maintenance mode to still be able >>> to upgrade to a newer version. Similarly, GWT has traditionally only >>> supported the current release, with no fixes backported, due to the extra >>> work that would need to be done in testing, backporting, etc. >>> >>> >>> To get stuck on a tangent before even reaching the point of this post, >>> this is part of the reason that each of the GWT modules which previously >>> lived in gwt-user.jar is getting its own git repo, and being released as >>> its own pace, separate from the GWT compiler and its neighbors (and also >>> separate from J2CL, with tests to ensure it can work with both toolkits). >>> Migrating to a specific version of one of those modules might require some >>> code changes be made to a project, but is intended to uncouple changes to >>> that project from changes made to either J2CL or GWT2 toolchains. >>> >>> GWT 2.10 has been released, with a few important changes that border on >>> breaking - the groupId has changed from com.google.gwt to org.gwtproject, >>> Jetty was updated after languishing for years, and IE 8, 9, and 10 support >>> has been dropped. The Jetty change has caused a few minute hiccups, one of >>> which will probably result in a GWT 2.10.1 release, but otherwise things >>> seem to have gone well. >>> >>> Looking forward, we have some other decisions to make around deprecating >>> or dropping support for certain features or compatibility. The chief issue >>> is dropping support for Java 8. Jetty 9 is EOL (though still receiving >>> occasional security updates for now), and Jetty 10 requires Java 11 at a >>> minimum. Recent versions of the Eclipse JDT will also require Java 11, so >>> we can’t add support for Java 17 language features without dropping support >>> for running on Java 8. While it is possible that we might be able to >>> continue to compile gwt-servlet and other production server-side code for >>> Java 8, that is going to need dedicated testing to ensure it behaves as we >>> expect, so I wouldn’t want to have it be one of our first choices. >>> >>> We would be in good company with dropping Java 8 in our next release - >>> the Spring Framework has gone so far as to drop Java 11 support as well, >>> requiring Java 17 as the minimum supported Java version as of version 6 >>> <https://spring.io/blog/2022/03/28/an-update-on-java-17-adoption>. >>> >>> Other deprecations/updates/removals to consider - I haven’t spent a >>> great deal of time investigating any of these, but wanted to at least open >>> the door to some of these. >>> >>> >>> - Legacy Dev Mode - the use cases are diminishing but not totally >>> gone yet. IE11 technically supports it, and HtmlUnit can use it as well. >>> Some testing tools like gwt-mockito and Emma require it as well. With >>> that >>> said, if removed, there is considerable old code that can go with it, >>> not >>> just in the compiler and dev mode, but simplification that can happen in >>> emulation as well. >>> - Selenium - Selenium support is ancient, and I’m not aware of a way >>> to make it work with recent browsers. Moving to modern WebDriver would >>> make >>> sense, though this is a bit of a moving target in my experience, but >>> downstream projects should be able to update without affecting GWT. It >>> might even make sense to leave this as an optional dependency, and rely >>> on >>> the downstream project adding its own implementation. >>> - javax.servlet -> jakarta.servlet - This could potentially be done >>> in a way to support both APIs in a single release, though that may also >>> require supporting two sets of dev mode implementations, for users that >>> run >>> their own servlets in the dev mode server. >>> >>> >>> Inevitably, removing these before they are formally end-of-life’d is >>> bound to inconvenience at least a few downstream developers, so this isn’t >>> to be taken lightly, nor done without some plan to continue to support >>> critical fixes. Some quick options, based on how much pushback we get on >>> each: >>> >>> - Keep all compatibility until the dependency in question is >>> formally end-of-life’d. We’ll be waiting until something like 2026 to >>> pick >>> up the Java 17 support through JDT, though other options might be >>> possible >>> along the way. >>> - Be very aggressive in dropping support, such as Spring’s model, >>> where the next release will only support Java 17+. This will undoubtedly >>> cut off support for many projects far before they are ready to update. >>> - Let the main branch work towards updating some of these >>> dependencies for a 2.11 release, and backport any fixes that don’t >>> directly >>> relate to upgrades to the release/2.10 branch. This would represent a >>> shift >>> in existing policy around releases, and might require more support from >>> community members for testing and such. There is also the risk that 2.10 >>> could miss out on some fixes. As the “current version” of Java is going >>> to >>> keep on marching forward, likely 2.12 and so on would continue to be >>> released, and 2.10 would remain the “LTS” version. >>> - Same as above, but let 2.11 become the LTS release (so as to give >>> the project time to adapt to being moved to GitHub, and to get a 2.10.1 >>> out >>> to fix known regressions), and let 2.12+ feel comfortable dropping >>> support >>> for Java 8, etc. >>> - Same as above, but a more complex plan where more than one version >>> is maintained long-term, to allow (for example) 2.11 to drop Java 8, >>> 2.12 >>> to drop javax.servlet, 2.13 to drop Java 11 and so on. This could easily >>> explode out of control with many backported fixes to manage and test. >>> >>> >>> I don’t want to dwell too much yet on exactly what should be dropped and >>> when, at least until some initial conversation is had on generally handling >>> deprecations and potentially picking a potential strategy for keeping a >>> “LTS”-style release. Then, discuss community support needs for the various >>> dependencies in a broader audience, and make decisions from there. >>> >>> Thoughts on how to generally balance deprecations against updates? >>> >> -- You received this message because you are subscribed to the Google Groups "GWT Contributors" group. To unsubscribe from this group and stop receiving emails from it, send an email to google-web-toolkit-contributors+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/google-web-toolkit-contributors/ca5b45ea-c02b-4f57-8ac8-6122dfa69ce4n%40googlegroups.com.
