Ignore classes defined in the unnamed pckg inside BeanArchives.index

fixes: #26524

independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/BeanArchives.java

@@ -19,6 +19,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.regex.Pattern;
 import javax.enterprise.context.BeforeDestroyed;
 import javax.enterprise.context.Destroyed;
 import javax.enterprise.context.Initialized;
@@ -43,6 +44,8 @@ public final class BeanArchives {
 
     private static final Logger LOGGER = Logger.getLogger(BeanArchives.class);
 
+    private static final Pattern MISSING_PACKAGE_PATTERN = Pattern.compile("[^.]+");
+
     /**
      *
      * @param applicationIndexes
@@ -279,6 +282,10 @@ static boolean index(Indexer indexer, String className, ClassLoader classLoader)
             // Ignore primitives and arrays
             return false;
         }
+        if (isInUnnamedPackage(className)) {
+            LOGGER.debugf("Class %s is defined in the unnamed package that is not indexed", className);
+            return false;
+        }
         try (InputStream stream = classLoader
                 .getResourceAsStream(className.replace('.', '/') + ".class")) {
             if (stream != null) {
@@ -292,4 +299,8 @@ static boolean index(Indexer indexer, String className, ClassLoader classLoader)
         }
         return result;
     }
+
+    private static boolean isInUnnamedPackage(String className) {
+        return MISSING_PACKAGE_PATTERN.matcher(className).matches();
+    }
 }

independent-projects/arc/processor/src/test/java/io/quarkus/arc/processor/BeanArchivesTest.java

@@ -0,0 +1,16 @@
+package io.quarkus.arc.processor;
+
+import org.jboss.jandex.Indexer;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class BeanArchivesTest {
+
+    @Test
+    public void testIndex() {
+        final Indexer indexer = new Indexer();
+        Assertions.assertFalse(BeanArchives.index(indexer, "String"));
+        Assertions.assertTrue(BeanArchives.index(indexer, String.class.getName()));
+    }
+
+}