Drop support for Java 8, make Java 11 the minimum

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
         # NOTE(olafurpg) Windows is not enabled because it times out due to reasons I don't understand.
         # os: [windows-latest, ubuntu-latest]
         os: [ubuntu-latest]
-        java: [8, 11, 17, 21]
+        java: [11, 17, 21]
     steps:
       - uses: actions/checkout@v4
 
@@ -140,7 +140,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        java: [8, 11, 17, 21]
+        java: [11, 17, 21]
     steps:
       - uses: actions/checkout@v4
 

.github/workflows/release-cli.yml

@@ -17,7 +17,7 @@ jobs:
       - uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
-          java-version: 8
+          java-version: 11
 
       - uses: coursier/setup-action@v3
         with:

.github/workflows/release-docker.yml

@@ -14,7 +14,7 @@ jobs:
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
-          java-version: 8
+          java-version: 11
           cache: 'sbt'
       - uses: sbt/setup-sbt@v1
       - uses: docker/setup-buildx-action@v1

.github/workflows/release-maven.yml

@@ -14,7 +14,7 @@ jobs:
       - uses: actions/setup-java@v3
         with:
           distribution: 'temurin'
-          java-version: 8
+          java-version: 11
           cache: 'sbt'
       - uses: sbt/setup-sbt@v1
       - name: Publish ${{ github.ref }}

bin/docker-setup.sh

@@ -15,7 +15,7 @@ rm gradle.zip
 mv /opt/gradle/*/* /opt/gradle
 
 # pre-install JDK for all major versions
-for JVM_VERSION in 21 17 11 8
+for JVM_VERSION in 21 17 11
 do 
   coursier java --jvm $JVM_VERSION --jvm-index https://github.com/coursier/jvm-index/blob/master/index.json -- -version
 done

build.sbt

@@ -88,7 +88,6 @@ lazy val agent = project
   .settings(
     fatjarPackageSettings,
     javaOnlySettings,
-    javaToolchainVersion := "8",
     moduleName := "semanticdb-agent",
     libraryDependencies ++=
       List(
@@ -110,8 +109,7 @@ lazy val gradlePlugin = project
     scalaVersion := V.scala213,
     buildInfoPackage := "com.sourcegraph.scip_java",
     publish / skip := true,
-    javaToolchainVersion := "8",
-    scalacOptions ++= Seq("-target:8", "-release", "8"),
+    scalacOptions ++= Seq("-target:11", "-release", "11"),
     libraryDependencies ++=
       List(
         "dev.gradleplugins" % "gradle-api" % V.gradle % Provided,
@@ -150,7 +148,6 @@ lazy val javacPlugin = project
     fatjarPackageSettings,
     javaOnlySettings,
     moduleName := "semanticdb-javac",
-    javaToolchainVersion := "8",
     javacOptions += "-g",
     (assembly / assemblyShadeRules) :=
       Seq(
@@ -186,7 +183,6 @@ lazy val scipProto = project
   .in(file("scip-java-proto"))
   .settings(
     moduleName := "scip-java-proto",
-    javaToolchainVersion := "8",
     javaOnlySettings,
     libraryDependencies +=
       "com.google.protobuf" % "protobuf-java-util" % V.protobuf,
@@ -200,7 +196,6 @@ lazy val scip = project
   .settings(
     publishMavenStyle := true,
     moduleName := "scip-semanticdb",
-    javaToolchainVersion := "8",
     javaOnlySettings,
     (Compile / PB.targets) :=
       Seq(PB.gens.java(V.protobuf) -> (Compile / sourceManaged).value),
@@ -212,7 +207,6 @@ lazy val mavenPlugin = project
   .in(file("maven-plugin"))
   .settings(
     moduleName := "maven-plugin",
-    javaToolchainVersion := "8",
     javaOnlySettings,
     libraryDependencies ++=
       Seq(
@@ -388,12 +382,6 @@ lazy val minimized = project
   .dependsOn(agent, javacPlugin)
   .disablePlugins(JavaFormatterPlugin)
 
-lazy val minimized8 = project
-  .in(file("tests/minimized/.j8"))
-  .settings(minimizedSettings, javaToolchainVersion := "8", javaOnlySettings)
-  .dependsOn(agent, javacPlugin)
-  .disablePlugins(JavaFormatterPlugin)
-
 def javacModuleOptions = List(
   "-J--add-exports",
   "-Jjdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED",

docs/contributing.md

@@ -95,6 +95,4 @@ write tests because:
   [snapshot testing](https://jestjs.io/docs/en/snapshot-testing), which is a
   testing technique that's heavily used in this codebase.
 - Multiline literal strings in Scala make it easy to write unit tests for source
-  code (which is always multiline). Modern versions of Java support multiline
-  string literals, but they're not supported in Java 8, which is supported by
-  scip-java.
+  code (which is always multiline).

docs/getting-started.md

@@ -35,7 +35,7 @@ finished indexing the project.
 
 > The `sourcegraph/scip-java` Docker image is made available for convenience at
 > the cost of performance. The `sourcegraph/scip-java` image is a big download
-> because it includes pre-installed versions of Java 8, Java 11, and Java 17.
+> because it includes pre-installed versions of Java 11, Java 17, and Java 21.
 > The `sourcegraph/scip-java` image has slow performance because it needs to
 > download all external dependencies of your codebase on every invocation.
 >
@@ -46,9 +46,6 @@ Java 17 is the default Java version in the `sourcegraph/scip-java` Docker image.
 Use the following commands to use a different JVM version:
 
 ```sh
-# Java 8
-docker run -v $(pwd):/sources --env JVM_VERSION=8 sourcegraph/scip-java:latest scip-java index
-
 # Java 11
 docker run -v $(pwd):/sources --env JVM_VERSION=11 sourcegraph/scip-java:latest scip-java index
 
@@ -227,9 +224,10 @@ of Java versions.
 | Java version | Support                      | Tracking issue |
 | ------------ | ---------------------------- | -------------- |
 | Java 7       | ❌                           |                |
-| Java 8       | ✅                           |                |
+| Java 8       | ❌                           |                |
 | Java 11      | ✅                           |                |
 | Java 17      | ✅, requires `--add-exports` |                |
+| Java 21      | ✅, requires `--add-exports` |                |
 
 For Java 17 and newer versions, the following JVM options are required:
 

docs/manual-configuration.md

@@ -135,8 +135,8 @@ targetroot directory.
 
 ```
 ❯ find $TARGETROOT -type f
-build/semanticdb-targetroot/META-INF/semanticdb/j8/src/test/java/example/ExampleTest.java.semanticdb
-build/semanticdb-targetroot/META-INF/semanticdb/j8/src/main/java/example/Example.java.semanticdb
+build/semanticdb-targetroot/META-INF/semanticdb/j11/src/test/java/example/ExampleTest.java.semanticdb
+build/semanticdb-targetroot/META-INF/semanticdb/j11/src/main/java/example/Example.java.semanticdb
 ...
 ```
 

examples/maven-example/pom.xml

@@ -14,8 +14,8 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
         <revision>1.0.0-SNAPSHOT</revision>
     </properties>
 

maven-plugin/src/main/resources/META-INF/maven/plugin.template.xml

@@ -11,7 +11,7 @@
   <goalPrefix>sourcegraph</goalPrefix>
   <isolatedRealm>false</isolatedRealm>
   <inheritedByDefault>true</inheritedByDefault>
-  <requiredJavaVersion>1.8</requiredJavaVersion>
+  <requiredJavaVersion>11</requiredJavaVersion>
   <requiredMavenVersion>3.9.5</requiredMavenVersion>
   <mojos>
     <mojo>

project/JavaToolchainPlugin.scala

@@ -27,50 +27,16 @@ object JavaToolchainPlugin extends AutoPlugin {
   import autoImport._
 
   override lazy val projectSettings: Seq[Def.Setting[_]] = List(
-    javacOptions ++=
-      List(
-        "-target",
-        "1.8",
-        "-source",
-        "1.8",
-        "-bootclasspath",
-        java8Bootclasspath()
-      ),
-    (doc / javacOptions) --= List("-target", "1.8"),
-    (doc / javacOptions) --= bootclasspathSettings(javaToolchainVersion.value),
+    javacOptions ++= List("--release", "11"),
+    (doc / javacOptions) --= List("--release", "11"),
     (doc / javacOptions) --= List("-g"),
-    javacOptions ++= bootclasspathSettings(javaToolchainVersion.value),
-    javaOptions ++= bootclasspathSettings(javaToolchainVersion.value),
     fork := true,
     javaToolchainVersion := "11",
     javaToolchainJvmIndex := None,
     javaHome :=
       Some(getJavaHome(javaToolchainVersion.value, javaToolchainJvmIndex.value))
   )
 
-  /**
-   * For Java 8, we need to manually add the Java compiler to the boot
-   * classpath.
-   *
-   * Newer Java versions include the compiler by default.
-   */
-  private def bootclasspathSettings(version: String): List[String] = {
-    val home = getJavaHome(version)
-    val toolsJar: File = home / "lib" / "tools.jar"
-    // The tools.jar file includes the bytecode for the Java compiler in the com.sun.source package.
-    // The Java compiler is available by default in Java 9+, so we only need to add tools.jar to the
-    // bootclasspath for Java 8.
-    if (version == "8" && toolsJar.isFile) {
-      List(s"-Xbootclasspath/p:$toolsJar")
-    } else {
-      List()
-    }
-  }
-
-  private def java8Bootclasspath(): String = {
-    (getJavaHome("8") / "jre" / "lib" / "rt.jar").toString
-  }
-
   private val javaHomeCache: util.Map[String, File] = Collections
     .synchronizedMap(new util.HashMap[String, File]())
   private def getJavaHome(
@@ -85,28 +51,14 @@ object JavaToolchainPlugin extends AutoPlugin {
           .toList
           .flatMap(index => "--jvm-index" :: index :: Nil)
         val arguments =
-          List(
-            "java",
-            "-jar",
-            coursier.toString,
-            "java-home",
-            "--jvm",
-            jvmName(v)
-          ) ++ index
+          List("java", "-jar", coursier.toString, "java-home", "--jvm", v) ++
+            index
 
         new File(Process(arguments).!!.trim)
       }
     )
   }
 
-  private def jvmName(version: String) =
-    version match {
-      case "8" if isAppleM1 =>
-        "zulu:8" // the only Java 8 distribution available for Apple M1 is Zulu
-      case _ =>
-        version
-    }
-
   private def isAppleM1 =
     scala.util.Properties.isMac && sys.props("os.arch") == "aarch64"
 

scip-java/src/main/scala/com/sourcegraph/scip_java/buildtools/GradleJavaCompiler.scala

@@ -122,21 +122,13 @@ case class GradleJavaCompiler(languageVersion: String, javacPath: Path) {
 
     // For compile{Test}Kotlin when using jvm toolchains, we need to have access
     // to JDK internals found in <java-installation-path>/lib in JDK 9+,
-    // as well as <java-installation-path>/jre/lib in JDK <=8, else we get
-    // "no class roots are found in the JDK path" from the compile{Test}Kotlin tasks.
+    // else we get "no class roots are found in the JDK path" from the
+    // compile{Test}Kotlin tasks.
     // https://docs.oracle.com/en/java/javase/12/migrate/index.html#JSMIG-GUID-A78CC891-701D-4549-AA4E-B8DD90228B4B
     val javaHome = javacPath.getParent.getParent
     val libPath = dir.resolve("lib")
     val javacLibPath = javaHome.resolve("lib")
     copyFiles(javacLibPath, libPath)
-
-    if (languageVersion == "8") {
-      val jreLibPath = dir.resolve("jre").resolve("lib")
-      Files.createDirectories(jreLibPath.getParent)
-      val javacJreLibPath = javaHome.resolve("jre").resolve("lib")
-
-      copyFiles(javacJreLibPath, jreLibPath)
-    }
   }
 }
 object GradleJavaCompiler {
@@ -150,9 +142,9 @@ object GradleJavaCompiler {
   /**
    * Parses a single space-separated line into a GradleJavaCompiler instance.
    *
-   * Example input: "8 /javacLibPath/javac"
+   * Example input: "11 /javacLibPath/javac"
    *
-   * Example output: `Some(GradleJavaCompiler("8", * /javacLibPath/javac))`
+   * Example output: `Some(GradleJavaCompiler("11", * /javacLibPath/javac))`
    */
   def fromLine(line: String): Option[GradleJavaCompiler] =
     line.split(' ') match {

scip-java/src/main/scala/com/sourcegraph/scip_java/buildtools/ScipBuildTool.scala

@@ -77,7 +77,7 @@ import os.SubprocessException
  * {{{
  *   {
  *     "dependencies": ["junit:junit:4.13.1"],
- *     "jvm": "8"
+ *     "jvm": "11"
  *   }
  * }}}
  */
@@ -565,11 +565,7 @@ class ScipBuildTool(index: IndexCommand) extends BuildTool("SCIP", index) {
     })
     val javac = javacPath(config, tmp)
     index.app.reporter.info(s"$$ $javac @$argsfile")
-    val javacModuleOptions: Seq[String] =
-      if (config.jvm != "8")
-        BuildInfo.javacModuleOptions
-      else
-        Nil
+    val javacModuleOptions: Seq[String] = BuildInfo.javacModuleOptions
 
     val jvmOptions = config.jvmOptions.map("-J" + _)
 
@@ -671,16 +667,8 @@ class ScipBuildTool(index: IndexCommand) extends BuildTool("SCIP", index) {
 
   }
 
-  private def jvmArchitecture(jvm: String): String =
-    if (
-      // Hack only for local development on ARM64 Mac OS X
-      // won't affect any other system
-      scala.util.Properties.isMac && sys.props("os.arch") == "aarch64" &&
-      (jvm.startsWith("8") || jvm.startsWith("1.8"))
-    )
-      "amd64"
-    else
-      JvmIndex.defaultArchitecture()
+  private def jvmArchitecture(jvm: String): String = JvmIndex
+    .defaultArchitecture()
 
   def defaultCoursierJVMArchitecture: String =
     sys.props("os.arch") match {

scip-java/src/main/scala/com/sourcegraph/scip_java/commands/IndexDependencyCommand.scala

@@ -99,7 +99,7 @@ final case class IndexDependencyCommand(
   }
 
   private def inferJvmVersion(jar: Path): Option[Int] = {
-    Option(JavaVersion.classfileJvmVersion(jar).orElse(8)).map(
+    Option(JavaVersion.classfileJvmVersion(jar).orElse(11)).map(
       JavaVersion.roundToNearestStableRelease(_)
     )
   }