feat(provider): add language level detection

Add a new function `detectLanguageLevel` to the `JavaBuildSystemProvider` class. This function is used to determine the language level of the Java project. It first checks the project SDK and if not found, it checks the module SDK. The detected language level is then used to set the `languageVersion` property in the `DockerfileContext` object. This feature enhances the accuracy of language version

Author: phodal

java/src/233/main/kotlin/cc/unitmesh/idea/provider/JavaBuildSystemProvider.kt

@@ -4,8 +4,18 @@ import cc.unitmesh.devti.provider.BuildSystemProvider
 import cc.unitmesh.devti.template.context.DockerfileContext
 import com.intellij.openapi.externalSystem.service.project.ProjectDataManager
 import com.intellij.openapi.externalSystem.service.ui.completion.TextCompletionInfo
+import com.intellij.openapi.module.LanguageLevelUtil
+import com.intellij.openapi.module.Module
+import com.intellij.openapi.module.ModuleManager
+import com.intellij.openapi.module.ModuleUtilCore
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.project.guessProjectDir
+import com.intellij.openapi.projectRoots.JavaSdkType
+import com.intellij.openapi.roots.ModuleRootManager
+import com.intellij.openapi.roots.ProjectRootManager
+import com.intellij.pom.java.LanguageLevel
+import com.intellij.psi.PsiFile
+import com.intellij.psi.util.PsiUtil
 import com.intellij.util.lang.JavaVersion
 import org.jetbrains.plugins.gradle.service.project.GradleTasksIndices
 import org.jetbrains.plugins.gradle.util.GradleConstants
@@ -33,19 +43,36 @@ open class JavaBuildSystemProvider : BuildSystemProvider() {
             buildToolName = "Maven"
         }
 
-        val javaVersion = JavaVersion.current()
-        val javaVersionStr = "${javaVersion.feature}"
+        val javaVersion = detectLanguageLevel(project, null)
 
         return DockerfileContext(
             buildToolName = buildToolName,
             buildToolVersion = "",
             languageName = "Java",
-            languageVersion = javaVersionStr,
+            languageVersion = "$javaVersion",
             taskString = taskString
         )
     }
 
     companion object {
+        fun detectLanguageLevel(project: Project, sourceFile: PsiFile?): LanguageLevel? {
+            val projectSdk = ProjectRootManager.getInstance(project).projectSdk
+            if (projectSdk != null) {
+                if (projectSdk.sdkType !is JavaSdkType) return null
+                return PsiUtil.getLanguageLevel(project)
+            }
+
+            var moduleOfFile = ModuleUtilCore.findModuleForFile(sourceFile)
+            if (moduleOfFile == null) {
+                moduleOfFile = ModuleManager.getInstance(project).modules.firstOrNull() ?: return null
+            }
+
+            val sdk = ModuleRootManager.getInstance(moduleOfFile).sdk ?: return null
+            if (sdk.sdkType !is JavaSdkType) return null
+
+            return LanguageLevelUtil.getEffectiveLanguageLevel(moduleOfFile)
+        }
+
         val GRADLE_COMPLETION_COMPARATOR = Comparator<String> { o1, o2 ->
             when {
                 o1.startsWith("--") && o2.startsWith("--") -> o1.compareTo(o2)