com.google.maps.android:maps-ktx:5.1.0 requires Java 17 runtime

[mateuszkwiecinski]

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Environment details

1. Specify the API at the beginning of the title (for example, "Places: ..."): Kotlin Compiler
2. OS type and version: Yes
3. Library version and other environment information: `com.google.maps.android:maps-ktx:5.1.0

Steps to reproduce

1. Have an build that produces java 11 compatible bytecode i..e

android.kotlinOptions.jvmTarget = JavaVersion.VERSION_11.toString()

or whatever it is preferred these days
2. Call com.google.maps.android.ktx.awaitMap in the source code
3. Compile the app

Expected: The project compiles just fine
Actual: compileDebugKotlin fails with Cannot inline bytecode built with JVM target 17 into bytecode that is being built with JVM target 11. Please specify proper '-jvm-target' option.

My reasoning why this is a bug:

• Such breaking change was released in minor version bump. I'm not sure which java version targets 5.0.0 but it compiles just fine for a project targeting Java 11
• Release notes don't mention that change at all

• only some of Java 11 and 17 APIs are available via desugaring on Android, we're still far from most of the devices being able to run (even desugared) Java 17 code. Plus desugaring isn't yet enforced or even enabled by default
• According to https://developer.android.com/build/jdks#compileSdk Java 17 runtime is available only starting from API 34

More insights:

• PR responsible for this change: chore: setting Java 17 for the release flow #261
• A fix would be to set the target version for the lowest possible version since you're aiming to support down to API 21

Related articles:

• https://jakewharton.com/build-on-latest-java-test-through-lowest-java/
• https://jakewharton.com/kotlins-jdk-release-compatibility-flag/

Code example

# example
fun repro(map : com.google.android.gms.maps.MapView) = map.awaitMap()

Stack trace

# example
`Cannot inline bytecode built with JVM target 17 into bytecode that is being built with JVM target 11. Please specify proper '-jvm-target' option.`

Following these steps will guarantee the quickest resolution possible.

Thanks!

[kikoso]

Hi @mateuszkwiecinski , thanks for opening this issue.

Actually, this problem goes further in the past. In January we updated some of our libraries to include an upgrade in the Android Gradle Plugin from 7.x to 8.x. This requires us to update the Java version to 17, to support the new plugin version.

This didn't trigger a release and I can't recall the specific reason, but it should have been a major release (i.e., 6.0.0). The current 5.1.0 release includes this new AGP version and some other updates.

I am not sure if it could be worth to release a "lean" 6.0.0 to reflect the breaking change. Probably it could. I am updating also the release notes to reflect this new change.

[mateuszkwiecinski]

This requires us to update the Java version to 17, to support the new plugin version.

But that's only for the build, right? The runtime was not affected by AGP bump, was it?

My understanding is you can compile the project with latest java version, but still release artifacts compatible with lower Java versions. Or is it now required for library runtime to use Java 17 features specifically?

[mateuszkwiecinski]

I wanted to check what forced you to bump target version and opened: #267
It passed for me locally, including local publishing.

javap -v ~/.m2/repository/com/google/maps/android/maps-utils-ktx/5.1.0/maps-utils-ktx-5.1.0/classes/com/google/maps/android/ktx/utils/LatLngKt.class | grep major

Confirms java 11 compatibility 👀

[kikoso]

My understanding is you can compile the project with latest java version, but still release artifacts compatible with lower Java versions

This is correct. I honestly do not recall why the Java version was updated back in January, unfortunately logs for past GitHub actions are not available.

The PR you open looks good. Would you mind signing the Google CLA?.

I am thinking of whether this should trigger a minor release. It is technically not a breaking change, but the changes that were merged in January and didn't trigger a release are.

[mateuszkwiecinski]

The PR you open looks good. Would you mind signing the Google CLA?.

Sure, done ✅

I am thinking of whether this should trigger a minor release

I'm not sure what the versioning policy here is. I can propose downgrading the target version further, down to 1.8 as it was it 5.0.0, that way a patch release 5.1.1 would be enough as it will not introduce breaking changes since last major release. That way you could discuss internally which Android runtimes you want to officially support and decide at your own pace

If you keep setup from 5.1.0 and accidentaly start using Java 17 APIs (assuming consumers don't use desugaring), you can start crashing in runtime on devices with API < 34 and nothing will warn you about that. Setup from my PR can crash in runtime on devices with API <29. Downgrading target java version to 1.8 should always work down to API 21 (the one that is mentioned in project's Readme)

[kikoso]

I have changed the title to fix: bring back Java 11 compatibility, which should trigger the release 5.1.1.

Leaving some comments on the PR for transparency.