Skip printing JNICache for non enum types.

Author: sidepelican

Sources/JExtractSwiftLib/JNI/JNISwift2JavaGenerator+SwiftThunkPrinting.swift

@@ -174,6 +174,10 @@ extension JNISwift2JavaGenerator {
   }
 
   private func printJNICache(_ printer: inout CodePrinter, _ type: ImportedNominalType) {
+    if type.cases.isEmpty {
+      return
+    }
+    
     printer.printBraceBlock("enum \(JNICaching.cacheName(for: type))") { printer in
       for enumCase in type.cases {
         guard let translatedCase = translatedEnumCase(for: enumCase) else { continue }