Downgrade okhttp to 4.11.0 upgrade Kotlin to 1.9

Uses Kotlin 1.9 to compile but remains compatible with Kotlin 1.7. For this, we need to be on OkHttp 4.11.0. Upgrading to 4.12.0 makes Kotlin 1.7 not work in the sample.

build.gradle

@@ -88,6 +88,8 @@ subprojects {
 
             toolchain {
                 languageVersion = javaLanguageVersion
+                sourceCompatibility = javaTargetVersion
+                targetCompatibility = javaTargetVersion
             }
         }
 
@@ -117,6 +119,9 @@ subprojects {
             compileTestJava {
                 options.encoding = 'UTF-8'
                 options.compilerArgs << '-Xlint:unchecked' << '-Xlint:deprecation'
+
+                sourceCompatibility = 11
+                targetCompatibility = 11
             }
 
 

gradle/libs.versions.toml

@@ -61,7 +61,8 @@ mockito = "5.8.0"
 mongo = "4.11.1"
 netty = "4.1.104.Final"
 newrelic-api = "5.14.0"
-okhttp = "5.0.0-alpha.11" # TODO is compiling against an alpha version intentional?
+# Kotlin 1.7 sample will fail from OkHttp 4.12.0 due to okio dependency being a Kotlin 1.9 module
+okhttp = "4.11.0"
 postgre = "42.7.1"
 prometheus = "0.16.0"
 reactor = "2022.0.13"

micrometer-core/build.gradle

@@ -1,5 +1,5 @@
 plugins {
-    alias(libs.plugins.kotlin17)
+    alias(libs.plugins.kotlin19)
     id 'me.champeau.mrjar' version "0.1.1"
 }
 
@@ -12,12 +12,14 @@ multiRelease {
 tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).all {
     kotlinOptions {
         jvmTarget = javaTargetVersion
+        apiVersion = "1.7"
+        languageVersion = "1.7"
     }
 }
 
-tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinTest).all {
+compileTestKotlin {
     kotlinOptions {
-        jvmTarget = JavaVersion.toVersion(javaLanguageVersion)
+        jvmTarget = 11
     }
 }
 
@@ -273,3 +275,8 @@ java11Test {
         maxRetries = 3
     }
 }
+
+compileJava11TestJava {
+    sourceCompatibility = 11
+    targetCompatibility = 11
+}

micrometer-jetty11/build.gradle

@@ -8,6 +8,10 @@ dependencies {
     testImplementation 'org.assertj:assertj-core'
 }
 
+java {
+    targetCompatibility = 11
+}
+
 compileJava {
     sourceCompatibility = JavaVersion.VERSION_11
     targetCompatibility = JavaVersion.VERSION_11

micrometer-test/build.gradle

@@ -80,3 +80,8 @@ java11Test {
         maxRetries = 3
     }
 }
+
+compileJava11TestJava {
+    sourceCompatibility = 11
+    targetCompatibility = 11
+}

samples/micrometer-samples-javalin/build.gradle

@@ -11,6 +11,10 @@ dependencies {
     implementation 'ch.qos.logback:logback-classic'
 }
 
+java {
+    targetCompatibility = 11
+}
+
 compileJava {
     sourceCompatibility = JavaVersion.VERSION_11
     targetCompatibility = JavaVersion.VERSION_11

samples/micrometer-samples-kotlin/build.gradle

@@ -1,6 +1,14 @@
 plugins {
-    // test with the highest version of Kotlin supported because we compile with oldest version supported
-    alias(libs.plugins.kotlin19)
+    // test with the lowest version of Kotlin supported because we compile with highest version supported
+    alias(libs.plugins.kotlin17)
+}
+
+tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).all {
+    kotlinOptions {
+        jvmTarget = javaTargetVersion
+        apiVersion = "1.7"
+        languageVersion = "1.7"
+    }
 }
 
 dependencies {