Support jspecify @nullable in configuration metadata processor and tests

- Switch tests to org.jspecify.annotations.Nullable and remove local org.springframework.lang.Nullable
- Recognize both org.springframework.lang.Nullable and org.jspecify.annotations.Nullable as optional in the processor (backward compatible)
- Add org.jspecify:jspecify as testCompileOnly (no runtime impact)

Signed-off-by: wonyongg <[email protected]>

Author: wonyongg

configuration-metadata/spring-boot-configuration-processor/build.gradle

@@ -36,6 +36,7 @@ architectureCheck {
 
 dependencies {
 	testCompileOnly("com.google.code.findbugs:jsr305:3.0.2")
+	testCompileOnly("org.jspecify:jspecify")
 
 	testImplementation(enforcedPlatform(project(":platform:spring-boot-dependencies")))
 	testImplementation(project(":test-support:spring-boot-test-support"))

configuration-metadata/spring-boot-configuration-processor/src/main/java/org/springframework/boot/configurationprocessor/MetadataGenerationEnvironment.java

@@ -56,7 +56,9 @@
  */
 class MetadataGenerationEnvironment {
 
-	private static final String NULLABLE_ANNOTATION = "org.springframework.lang.Nullable";
+	private static final Set<String> NULLABLE_ANNOTATIONS = Set.of(
+			"org.springframework.lang.Nullable",
+			"org.jspecify.annotations.Nullable");
 
 	private static final Set<String> TYPE_EXCLUDES = Set.of("com.zaxxer.hikari.IConnectionCustomizer",
 			"groovy.lang.MetaClass", "groovy.text.markup.MarkupTemplateEngine", "java.io.Writer", "java.io.PrintWriter",
@@ -375,7 +377,12 @@ AnnotationMirror getNameAnnotation(Element element) {
 	}
 
 	boolean hasNullableAnnotation(Element element) {
-		return getAnnotation(element, NULLABLE_ANNOTATION) != null;
+		for (String nullableAnnotation : NULLABLE_ANNOTATIONS) {
+			if (getAnnotation(element, nullableAnnotation) != null) {
+				return true;
+			}
+		}
+		return false;
 	}
 
 	boolean hasOptionalParameterAnnotation(Element element) {

configuration-metadata/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationsample/endpoint/NullableParameterEndpoint.java

@@ -18,7 +18,7 @@
 
 import org.springframework.boot.configurationsample.Endpoint;
 import org.springframework.boot.configurationsample.ReadOperation;
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * An endpoint with @Nullable parameter to test.