Display dynamic --jvm-target values when using --help flag

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/ArgumentConverters.kt

@@ -2,6 +2,7 @@ package io.gitlab.arturbosch.detekt.cli
 
 import com.beust.jcommander.IStringConverter
 import com.beust.jcommander.ParameterException
+import org.jetbrains.kotlin.config.JvmTarget
 import org.jetbrains.kotlin.config.LanguageVersion
 import java.io.File
 import java.net.URL
@@ -50,6 +51,11 @@ class LanguageVersionConverter : IStringConverter<LanguageVersion> {
         checkNotNull(LanguageVersion.fromFullVersionString(value)) { "Invalid value passed to --language-version" }
 }
 
+class JvmTargetConverter : IStringConverter<JvmTarget> {
+    override fun convert(value: String): JvmTarget =
+        checkNotNull(JvmTarget.fromString(value)) { "Invalid value passed to --jvm-target" }
+}
+
 class ClasspathResourceConverter : IStringConverter<URL> {
     override fun convert(resource: String): URL {
         val relativeResource = if (resource.startsWith("/")) resource else "/$resource"

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/CliArgs.kt

@@ -188,10 +188,11 @@ class CliArgs {
 
     @Parameter(
         names = ["--jvm-target"],
+        converter = JvmTargetConverter::class,
         description = "EXPERIMENTAL: Target version of the generated JVM bytecode that was generated during " +
-            "compilation and is now being used for type resolution (1.6, 1.8, 9, 10, 11, 12, 13, 14, 15, 16 or 17)"
+            "compilation and is now being used for type resolution"
     )
-    var jvmTarget: String = JvmTarget.DEFAULT.description
+    var jvmTarget: JvmTarget = JvmTarget.DEFAULT
 
     @Parameter(
         names = ["--version"],

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/Spec.kt

@@ -65,7 +65,7 @@ internal fun CliArgs.createSpec(output: Appendable, error: Appendable): Processi
         }
 
         compiler {
-            jvmTarget = args.jvmTarget
+            jvmTarget = args.jvmTarget.toString()
             languageVersion = args.languageVersion?.versionString
             classpath = args.classpath?.trim()
         }