aot improvements

Signed-off-by: Josh Long <54473+joshlong@users.noreply.github.com>

kerberos/kerberos-core/src/main/java/org/springframework/security/kerberos/aot/hint/KerberosRuntimeHints.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2004-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.security.kerberos.aot.hint;
+
+import org.jspecify.annotations.Nullable;
+
+import org.springframework.aot.hint.MemberCategory;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.RuntimeHintsRegistrar;
+import org.springframework.aot.hint.TypeReference;
+
+/**
+ * {@link RuntimeHintsRegistrar} for Kerberos authentication classes.
+ *
+ * @author Josh Long
+ */
+class KerberosRuntimeHints implements RuntimeHintsRegistrar {
+
+	@Override
+	public void registerHints(RuntimeHints hints, @Nullable ClassLoader classLoader) {
+		// Krb5LoginModule is referenced as a plain string in LoginConfig and loaded by
+		// JAAS via Class.forName at runtime, so it needs an explicit reflection hint.
+		hints.reflection()
+			.registerType(TypeReference.of("com.sun.security.auth.module.Krb5LoginModule"),
+					(builder) -> builder.withMembers(MemberCategory.INVOKE_DECLARED_CONSTRUCTORS,
+							MemberCategory.INVOKE_DECLARED_METHODS, MemberCategory.ACCESS_DECLARED_FIELDS));
+	}
+
+}

kerberos/kerberos-core/src/main/java/org/springframework/security/kerberos/aot/hint/package-info.java

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+/*
+ * Copyright 2004-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * AOT and native image hint support for Kerberos authentication.
+ */
+package org.springframework.security.kerberos.aot.hint;

kerberos/kerberos-core/src/main/resources/META-INF/spring/aot.factories

@@ -0,0 +1,2 @@
+org.springframework.aot.hint.RuntimeHintsRegistrar=\
+org.springframework.security.kerberos.aot.hint.KerberosRuntimeHints