Use Java SDK defined on JAVA_HOME by default on JetBrains IDEs

Author: felladrin

components/ide/jetbrains/backend-plugin/src/main/kotlin/io/gitpod/jetbrains/remote/GitpodProjectManager.kt

@@ -10,14 +10,17 @@ import com.intellij.openapi.module.Module
 import com.intellij.openapi.module.ModuleManager
 import com.intellij.openapi.project.ModuleListener
 import com.intellij.openapi.project.Project
+import com.intellij.openapi.projectRoots.JdkUtil
 import com.intellij.openapi.projectRoots.ProjectJdkTable
 import com.intellij.openapi.projectRoots.Sdk
 import com.intellij.openapi.roots.ModuleRootModificationUtil
 import com.intellij.openapi.roots.ProjectRootManager
+import com.intellij.openapi.vfs.VirtualFileManager
 import com.intellij.util.application
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.future.await
 import kotlinx.coroutines.launch
+import java.nio.file.Path
 import java.util.concurrent.CompletableFuture
 
 
@@ -29,19 +32,28 @@ class GitpodProjectManager(
         configureSdks()
     }
 
-    /**
-     * It is a workaround for https://youtrack.jetbrains.com/issue/GTW-88
-     */
     private fun configureSdks() {
         if (application.isHeadlessEnvironment) {
             return
         }
         val pendingSdk = CompletableFuture<Sdk>()
         application.invokeLaterOnWriteThread {
             application.runWriteAction {
+                val jdkTable = ProjectJdkTable.getInstance()
+                if (jdkTable.allJdks.isEmpty()) {
+                    jdkTable.preconfigure()
+                }
                 try {
-                    ProjectJdkTable.getInstance().preconfigure()
-                    pendingSdk.complete(ProjectJdkTable.getInstance().allJdks.firstOrNull())
+                    val javaHome = System.getenv("JAVA_HOME")
+                    if (javaHome !== null && JdkUtil.checkForJdk(javaHome)) {
+                        val javaHomeVirtualFile = VirtualFileManager.getInstance().findFileByNioPath(Path.of(javaHome))
+                        val sdk = jdkTable.getSdksOfType(jdkTable.defaultSdkType).find { sdk ->
+                            sdk.homeDirectory?.canonicalPath == javaHomeVirtualFile?.canonicalPath
+                        }
+                        pendingSdk.complete(sdk ?: jdkTable.allJdks.firstOrNull())
+                    } else {
+                        pendingSdk.complete(jdkTable.allJdks.firstOrNull())
+                    }
                 } catch (t: Throwable) {
                     pendingSdk.completeExceptionally(t)
                 }
@@ -58,24 +70,24 @@ class GitpodProjectManager(
             configureSdk(sdk)
         }
     }
-
+//  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" project-jdk-name="zulu-11" project-jdk-type="JavaSDK" />
     private fun configureSdk(sdk: Sdk) {
         application.invokeLaterOnWriteThread {
             application.runWriteAction {
                 val projectRootManager = ProjectRootManager.getInstance(project)
-                if (projectRootManager.projectSdk == null) {
+                if (projectRootManager.projectSdk != sdk) {
                     projectRootManager.projectSdk = sdk
                     thisLogger().warn("gitpod: '${project.name}' project: SDK was auto preconfigured: $sdk")
                 }
             }
         }
         for (module in ModuleManager.getInstance(project).modules) {
             ModuleRootModificationUtil.updateModel(module) { m ->
-                if (m.sdk == null) {
+                if (m.sdk != sdk) {
                     m.sdk = sdk
                     thisLogger().warn("gitpod: '${module.name}' module: SDK was auto preconfigured: $sdk")
                 }
             }
         }
     }
-}
+}