#1395: MetaModel Generator fails on Records

Signed-off-by: Lukas Jungmann <lukas.jungmann@oracle.com>

jpa/org.eclipse.persistence.jpa.modelgen/src/main/java/org/eclipse/persistence/internal/jpa/modelgen/visitors/ElementVisitor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2021 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2022 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at
@@ -37,6 +37,7 @@
 import javax.lang.model.element.VariableElement;
 import javax.lang.model.type.TypeMirror;
 import javax.lang.model.util.AbstractElementVisitor8;
+import javax.tools.Diagnostic;
 
 import org.eclipse.persistence.internal.helper.Helper;
 import org.eclipse.persistence.internal.jpa.metadata.MetadataLogger;
@@ -298,4 +299,10 @@ public MetadataField visitVariable(VariableElement variableElement, MetadataClas
 
         return field;
     }
+
+    @Override
+    public MetadataAnnotatedElement visitUnknown(Element e, MetadataClass metadataClass) {
+        processingEnv.getMessager().printMessage(Diagnostic.Kind.WARNING, "Unsupported element", e);
+        return null;
+    }
 }