Backwards compatablity

[adoble]

I am concerned that supporting backwards compatibility right back to Java 8 (see PR 53) will result in problems down the line (e.g. new functionality that uses other libraries, inability to use new features in Java that could lighten the coding workload). This was the reason for ADR 8.

However, as @wviana mentioned

Big enterprise projects using ADRs are probably not on the cutting edge java version.

So my proposal would be:

• Use the the latest Java LTS version for development (as per ADR 8)
• Provide backwards compatibly for two LTS versions before (e.g developed using Java 21, compatible with Java 11 - exactly as was done in PR 57)
• The old compatibility version is signaled as being deprecated. In our current case this means that version 11 is shown as deprecated
• Supersede ADR 8 to show this change.

Any thoughts on this?

[sdavids]

See comments in 07e8a69.

---

I suggest:

Gradle build

current LTS

adr-j/gradle/gradle-daemon-jvm.properties

Line 3 in 07e8a69

toolchainVersion=21

adr-j/build.gradle.kts

Line 25 in 07e8a69

languageVersion = JavaLanguageVersion.of(21)

Sources

src/main: release = current LTS - 2

adr-j/build.gradle.kts

Line 41 in 07e8a69

release = 11

src/test: release = current LTS

adr-j/build.gradle.kts

Line 25 in 07e8a69

languageVersion = JavaLanguageVersion.of(21)

So basically the current setup.

---

When a new LTS drops the following lines have to be changed:

adr-j/gradle/gradle-daemon-jvm.properties

Line 3 in 07e8a69

toolchainVersion=21

adr-j/build.gradle.kts

Line 25 in 07e8a69

languageVersion = JavaLanguageVersion.of(21)

adr-j/build.gradle.kts

Line 41 in 07e8a69

release = 11

The major version should be increased:

adr-j/build.gradle.kts

Line 20 in 07e8a69

version = "3.3.1"

The changelog/release notes should say something along the lines:

We have dropped support for Java version 11; the new minimum JRE version is 17.

[adoble]

Thanks for the review.

I've added some comments to the build script to highlight where things need to be changed and also created ADR 10 to cover binary compatibility.