remove @Autowired / leave only tests to show it is possible via meta-…

…annotation

core-processor/src/main/java/io/micronaut/inject/writer/BeanDefinitionWriter.java

@@ -27,7 +27,6 @@
 import io.micronaut.context.Qualifier;
 import io.micronaut.context.RequiresCondition;
 import io.micronaut.context.annotation.Any;
-import io.micronaut.context.annotation.Autowired;
 import io.micronaut.context.annotation.Bean;
 import io.micronaut.context.annotation.ConfigurationBuilder;
 import io.micronaut.context.annotation.ConfigurationProperties;
@@ -1831,7 +1830,7 @@ private void visitFieldInjectionPointInternal(
             boolean requiresReflection) {
 
         boolean isRequired = fieldElement
-            .booleanValue(AnnotationUtil.INJECT, Autowired.MEMBER_REQUIRED)
+            .booleanValue(AnnotationUtil.INJECT, AnnotationUtil.MEMBER_REQUIRED)
             .orElse(true);
         boolean requiresGenericType = false;
         Method methodToInvoke;
@@ -1954,7 +1953,7 @@ public void visitFieldValue(TypedElement declaringType,
             visitFieldInjectionPointInternal(declaringType, fieldElement, annotationMetadata, requiresReflection);
         } else if (!isConfigurationProperties || requiresReflection) {
             boolean isRequired = fieldElement
-                .booleanValue(AnnotationUtil.INJECT, Autowired.MEMBER_REQUIRED)
+                .booleanValue(AnnotationUtil.INJECT, AnnotationUtil.MEMBER_REQUIRED)
                 .orElse(true);
             visitFieldInjectionPointInternal(
                     declaringType,

core-processor/src/main/resources/META-INF/services/io.micronaut.inject.annotation.AnnotationTransformer

@@ -1,4 +1,3 @@
-io.micronaut.inject.annotation.internal.AutowiredTransformer
 io.micronaut.inject.annotation.internal.CoreNullableTransformer
 io.micronaut.inject.annotation.internal.CoreNonNullTransformer
 io.micronaut.inject.annotation.internal.KotlinNullableMapper

core/src/main/java/io/micronaut/core/annotation/AnnotationUtil.java

@@ -194,6 +194,10 @@ public Annotation[] getDeclaredAnnotations() {
      * The inherited annotation.
      */
     public static final String ANN_INHERITED = Inherited.class.getName();
+    /**
+     * The name of the required member.
+     */
+    public static final String MEMBER_REQUIRED = "required";
 
     private static final Map<Integer, List<String>> INTERN_LIST_POOL = new ConcurrentHashMap<>();
     private static final Map<String, Map<String, Object>> INTERN_MAP_POOL = new ConcurrentHashMap<>();

inject/src/main/java/io/micronaut/context/annotation/Autowired.java → inject-java/src/test/groovy/io/micronaut/inject/autowired/Autowired.java

@@ -13,8 +13,10 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package io.micronaut.context.annotation;
+package io.micronaut.inject.autowired;
 
+import io.micronaut.context.annotation.AliasFor;
+import io.micronaut.core.annotation.AnnotationUtil;
 import jakarta.inject.Inject;
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
@@ -36,10 +38,6 @@
 @Target({ElementType.ANNOTATION_TYPE, ElementType.FIELD, ElementType.METHOD})
 @Documented
 public @interface Autowired {
-    /**
-     * The name of the required member.
-     */
-    String MEMBER_REQUIRED = "required";
 
     /**
      * Specify whether the injection point is required.
@@ -56,7 +54,7 @@
      */
     @AliasFor(
         annotation = Inject.class,
-        member = MEMBER_REQUIRED
+        member = AnnotationUtil.MEMBER_REQUIRED
     )
     boolean required() default true;
 }

inject-java/src/test/groovy/io/micronaut/inject/autowired/AutowiredSpec.groovy

@@ -12,7 +12,7 @@ class AutowiredSpec extends AbstractTypeElementSpec {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import jakarta.inject.Singleton;
 
 @Singleton
@@ -37,7 +37,7 @@ class Foo {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import jakarta.inject.Singleton;
 
 @Singleton
@@ -61,7 +61,7 @@ class Foo {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import jakarta.inject.Singleton;
 
 @Singleton
@@ -84,7 +84,7 @@ record Foo(String name) {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import io.micronaut.context.annotation.Value;
 import jakarta.inject.Singleton;
 
@@ -110,7 +110,7 @@ class Foo {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import io.micronaut.context.annotation.Value;
 import jakarta.inject.Singleton;
 
@@ -145,7 +145,7 @@ record Foo(@Value("injected") String name) {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import io.micronaut.context.annotation.Value;
 import jakarta.inject.Singleton;
 
@@ -179,7 +179,7 @@ record Foo(String name) {
         def context = buildContext('''
 package test;
 
-import io.micronaut.context.annotation.Autowired;
+import io.micronaut.inject.autowired.Autowired;
 import io.micronaut.context.annotation.Value;
 import jakarta.inject.Singleton;
 

core-processor/src/main/java/io/micronaut/inject/annotation/internal/AutowiredTransformer.java → inject-java/src/test/groovy/io/micronaut/inject/autowired/AutowiredTransformer.java

@@ -13,9 +13,8 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package io.micronaut.inject.annotation.internal;
+package io.micronaut.inject.autowired;
 
-import io.micronaut.context.annotation.Autowired;
 import io.micronaut.core.annotation.AnnotationUtil;
 import io.micronaut.core.annotation.AnnotationValue;
 import io.micronaut.core.annotation.AnnotationValueBuilder;
@@ -32,8 +31,8 @@ public class AutowiredTransformer
     @Override
     public List<AnnotationValue<?>> transform(AnnotationValue<Autowired> annotation, VisitorContext visitorContext) {
         AnnotationValueBuilder<Annotation> builder = AnnotationValue.builder(AnnotationUtil.INJECT);
-        annotation.booleanValue(Autowired.MEMBER_REQUIRED)
-            .ifPresent(b -> builder.member(Autowired.MEMBER_REQUIRED, b));
+        annotation.booleanValue(AnnotationUtil.MEMBER_REQUIRED)
+            .ifPresent(b -> builder.member(AnnotationUtil.MEMBER_REQUIRED, b));
 
         return List.of(
             builder

inject-java/src/test/resources/META-INF/services/io.micronaut.inject.annotation.AnnotationTransformer

@@ -4,3 +4,4 @@ io.micronaut.aop.compile.AroundConstructCompileSpec$TestStereotypeAnnTransformer
 io.micronaut.annotation.mapping.TransformsToRepeatableAnnotationSpec$TheAnnotationTransformer
 io.micronaut.annotation.mapping.TransformNotInheritedAnnotationSpec$TheAnnotationMapper
 io.micronaut.annotation.mapping.TransformToInheritedAnnotationSpec$TheAnnotationMapper
+io.micronaut.inject.autowired.AutowiredTransformer

inject/src/main/java/io/micronaut/inject/InjectionPoint.java

@@ -16,7 +16,6 @@
 package io.micronaut.inject;
 
 import io.micronaut.context.Qualifier;
-import io.micronaut.context.annotation.Autowired;
 import io.micronaut.core.annotation.AnnotationMetadata;
 import io.micronaut.core.annotation.AnnotationMetadataProvider;
 
@@ -55,7 +54,7 @@ default Qualifier<T> getDeclaringBeanQualifier() {
      */
     static boolean isInjectionRequired(AnnotationMetadata annotationMetadata) {
         return annotationMetadata != null && annotationMetadata
-            .booleanValue(AnnotationUtil.INJECT, Autowired.MEMBER_REQUIRED)
+            .booleanValue(AnnotationUtil.INJECT, AnnotationUtil.MEMBER_REQUIRED)
             .orElse(true);
     }
 

src/main/docs/guide/ioc/injection/nullableInjection.adoc

@@ -0,0 +1,19 @@
+Occasionally it is desirable for injection to be optional (ie. not fail with a api:context.exceptions.NoSuchBeanException[] if there is no candidate bean available).
+
+For example if you are trying to build an extensible system where a default implementation is provided by the type but consumers of your API can provide a bean that, if available, will be injected.
+
+One way to make injection optional is to annotate the injected type with ann:core.annotation.Nullable[] which will result in `null` being injected by the framework if the bean is unavailable:
+
+.Example of Injecting `null`
+snippet::io.micronaut.docs.ioc.injection.nullable.Vehicle[indent="0"]
+
+<1> Here the constructor argument is annotated with ann:core.annotation.Nullable[]
+<2> Since there is no bean available `null` is injected and the code has to handle the possibility that the argument could be `null.
+
+Using ann:core.annotation.Nullable[] has the following considerations:
+
+* Can be used with any of the injection types (constructor, method or field injection)
+* Somewhere the code has to handle what happens if `null` is injected, for constructors this is easy since the constructor can handle the `null`, but for fields and methods a `@PostConstruct` method would need to be implemented to handle `null` if `null` is not desirable.
+* Finally, `@Nullable` cannot be used on primitive types like `int`, `long` etc. when using <<valueAnnotation, configuration injection>>. To handle primitives you need to specify `@Bindable(defaultValue="..")` and provide a default value.
+
+

src/main/docs/guide/ioc/injection/optionalInjection.adoc

@@ -1,21 +1,4 @@
-Occasionally it is desirable for injection to be optional (ie. not fail with a api:context.exceptions.NoSuchBeanException[] if there is no candidate bean available).
-
-For example if you are trying to build an extensible system where a default implementation is provided by the type but consumers of your API can provide a bean that, if available, will be injected.
-
-One way to make injection optional is to annotate the injected type with ann:core.annotation.Nullable[] which will result in `null` being injected by the framework if the bean is unavailable:
-
-.Example of Injecting `null`
-snippet::io.micronaut.docs.ioc.injection.nullable.Vehicle[indent="0"]
-
-<1> Here the constructor argument is annotated with ann:core.annotation.Nullable[]
-<2> Since there is no bean available `null` is injected and the code has to handle the possibility that the argument could be `null.
-
-Using ann:core.annotation.Nullable[] has the following considerations:
-
-* Can be used with any of the injection types (constructor, method or field injection)
-* Somewhere the code has to handle what happens if `null` is injected, for constructors this is easy since the constructor can handle the `null`, but for fields and methods a `@PostConstruct` method would need to be implemented to handle `null` if `null` is not desirable.
-* Finally, `@Nullable` cannot be used on primitive types like `int`, `long` etc. when using <<valueAnnotation, configuration injection>>. To handle primitives you need to specify `@Bindable(defaultValue="..")` and provide a default value.
-
+// THIS SECTION IS DISABLED. See https://github.com/micronaut-projects/micronaut-core/pull/10830
 An alternative to ann:core.annotation.Nullable[], is to make the injection optional (not to be confused with `java.util.Optional`). This can be done with the ann:context.annotation.Autowired[] annotation by setting the `required` member to `false`:
 
 .Example of Optional Injection with `@Autowired`

src/main/docs/guide/toc.yml

@@ -24,7 +24,7 @@ ioc:
     constructorInjection: Constructor Injection
     fieldInjection: Field Injection
     methodInjection: Method Injection
-    optionalInjection: Optional Injection
+    nullableInjection: Nullable Injection
   types: Injectable Container Types
   qualifiers: Bean Qualifiers
   typed: Limiting Injectable Types

test-suite-groovy/src/test/groovy/io/micronaut/docs/ioc/injection/optional/Vehicle.groovy

@@ -1,11 +1,13 @@
 package io.micronaut.docs.ioc.injection.optional
 
-import io.micronaut.context.annotation.Autowired
+// test disabled optional injection not supported
+// see https://github.com/micronaut-projects/micronaut-core/pull/10830 for discussion
+//import Autowired
 import jakarta.inject.Singleton
 
 @Singleton
 class Vehicle {
-    @Autowired(required = false) // <1>
+//    @Autowired(required = false) // <1>
     Engine engine = new Engine()
 
     void start() {

test-suite-kotlin/src/test/kotlin/io/micronaut/docs/ioc/injection/optional/Vehicle.kt

@@ -1,11 +1,13 @@
 package io.micronaut.docs.ioc.injection.optional
 
-import io.micronaut.context.annotation.Autowired
+// test disabled optional injection not supported
+// see https://github.com/micronaut-projects/micronaut-core/pull/10830 for discussion
+//import io.micronaut.inject.autowired.Autowired
 import jakarta.inject.Singleton
 
 @Singleton
 class Vehicle {
-    @Autowired(required = false)
+//    @io.micronaut.inject.autowired.Autowired(required = false)
     var engine:  Engine = Engine() // <1>
 
     fun start() {

test-suite/src/test/java/io/micronaut/docs/ioc/injection/optional/OptionalAutowiredTest.java

@@ -2,9 +2,11 @@
 
 import io.micronaut.test.extensions.junit5.annotation.MicronautTest;
 import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
 @MicronautTest(startApplication = false)
+@Disabled("optional injection is not supported")
 public class OptionalAutowiredTest {
     @Test
     void testVehicle(Vehicle vehicle) {

test-suite/src/test/java/io/micronaut/docs/ioc/injection/optional/Vehicle.java

@@ -1,12 +1,13 @@
 package io.micronaut.docs.ioc.injection.optional;
 
-import io.micronaut.context.annotation.Autowired;
+//import io.micronaut.context.annotation.Autowired;
 import jakarta.inject.Inject;
 import jakarta.inject.Singleton;
 
 @Singleton
 class Vehicle {
-    @Autowired(required = false) // <1>
+    //@Autowired(required = false) // <1>
+    @Inject
     Engine engine = new Engine(6);
 
     void start() {