build(gradle): Build with Java 21

This is a preparation for upgrading to ORT 35.0.0 which was built with
Java 21.

Signed-off-by: Sebastian Schuberth <[email protected]>

Author: sschuberth

build.gradle.kts

@@ -19,11 +19,17 @@
 
 import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
 
+import io.gitlab.arturbosch.detekt.Detekt
+
 import org.jetbrains.gradle.ext.GradleTask
 import org.jetbrains.gradle.ext.JarApplication
 import org.jetbrains.gradle.ext.runConfigurations
 import org.jetbrains.gradle.ext.settings
+import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
+
+val javaLanguageVersion: String by project
 
 plugins {
     // Apply core plugins.
@@ -46,6 +52,23 @@ configurations {
     resolvable("analyzerCliClasspath").get().extendsFrom(project.configurations["runtimeClasspath"])
 }
 
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(javaLanguageVersion)
+        vendor = JvmVendorSpec.ADOPTIUM
+    }
+}
+
+val maxKotlinJvmTarget = runCatching { JvmTarget.fromTarget(javaLanguageVersion) }
+    .getOrDefault(enumValues<JvmTarget>().max())
+
+tasks.withType<KotlinCompile> {
+    compilerOptions {
+        allWarningsAsErrors = true
+        jvmTarget = maxKotlinJvmTarget
+    }
+}
+
 val shadowJar = tasks.named<ShadowJar>("shadowJar") {
     archiveClassifier = "analyzer-cli"
 
@@ -140,3 +163,14 @@ detekt {
     config.from(files(".detekt.yml"))
     buildUponDefaultConfig = true
 }
+
+tasks.withType<Detekt>().configureEach {
+     jvmTarget = maxKotlinJvmTarget.target
+
+    reports {
+        xml.required.set(false)
+        html.required.set(false)
+        txt.required.set(false)
+        sarif.required.set(true)
+    }
+}

gradle.properties

@@ -0,0 +1,2 @@
+# Keep this aligned with `toolchainVersion` in `gradle/gradle-daemon-jvm.properties`.
+javaLanguageVersion = 21

gradle/gradle-daemon-jvm.properties

@@ -0,0 +1,3 @@
+# Keep this aligned with `javaLanguageVersion` in `gradle.properties`.
+toolchainVersion = 21
+toolchainVendor = Adoptium