Fix XA support for Oracle in native

We need to register a few more classes for reflection and also all their
nested classes, which is why I use `@RegisterForReflection` instead of
the usual build item.

Fixes quarkusio#23341

extensions/jdbc/jdbc-oracle/deployment/src/main/java/io/quarkus/jdbc/oracle/deployment/OracleNativeImage.java

@@ -2,6 +2,7 @@
 
 import io.quarkus.deployment.annotations.BuildProducer;
 import io.quarkus.deployment.annotations.BuildStep;
+import io.quarkus.deployment.builditem.AdditionalIndexedClassesBuildItem;
 import io.quarkus.deployment.builditem.nativeimage.ReflectiveClassBuildItem;
 
 /**
@@ -14,7 +15,8 @@ public final class OracleNativeImage {
      * by reflection, as commonly expected.
      */
     @BuildStep
-    void reflection(BuildProducer<ReflectiveClassBuildItem> reflectiveClass) {
+    void reflection(BuildProducer<ReflectiveClassBuildItem> reflectiveClass,
+            BuildProducer<AdditionalIndexedClassesBuildItem> additionalIndexedClasses) {
         //Not strictly necessary when using Agroal, as it also registers
         //any JDBC driver being configured explicitly through its configuration.
         //We register it for the sake of people not using Agroal.
@@ -23,6 +25,10 @@ void reflection(BuildProducer<ReflectiveClassBuildItem> reflectiveClass) {
         final String driverName = "oracle.jdbc.driver.OracleDriver";
         reflectiveClass.produce(ReflectiveClassBuildItem.builder(driverName).build());
 
+        // This is needed when using XA and we use the `@RegisterForReflection` trick to make sure all nested classes are registered for reflection
+        additionalIndexedClasses
+                .produce(new AdditionalIndexedClassesBuildItem("io.quarkus.jdbc.oracle.runtime.graal.OracleReflections"));
+
         // for ldap style jdbc urls. e.g. jdbc:oracle:thin:@ldap://oid:5000/mydb1,cn=OracleContext,dc=myco,dc=com
         //
         // Note that all JDK provided InitialContextFactory impls from the JDK registered via module descriptors

extensions/jdbc/jdbc-oracle/runtime/src/main/java/io/quarkus/jdbc/oracle/runtime/graal/OracleReflections.java

@@ -0,0 +1,13 @@
+package io.quarkus.jdbc.oracle.runtime.graal;
+
+import io.quarkus.runtime.annotations.RegisterForReflection;
+
+/**
+ * We don't use a build item here as we also need to register all the nested classes and there's no way to do it easily with the
+ * build item for now.
+ */
+@RegisterForReflection(targets = { oracle.jdbc.xa.OracleXADataSource.class,
+        oracle.jdbc.datasource.impl.OracleDataSource.class })
+public class OracleReflections {
+
+}