Nullability refinements and related polishing

jhoeller · jhoeller · commit 7f365942a5ef · 2020-10-13T00:08:15.000+02:00
diff --git a/spring-core/src/main/java/org/springframework/core/KotlinDetector.java b/spring-core/src/main/java/org/springframework/core/KotlinDetector.java
@@ -77,14 +77,13 @@ public static boolean isKotlinType(Class<?> clazz) {
 
 	/**
 	 * Return {@code true} if the method is a suspending function.
-	 *
 	 * @author Sebastien Deleuze
 	 * @since 5.3
 	 */
 	public static boolean isSuspendingFunction(Method method) {
 		if (KotlinDetector.isKotlinType(method.getDeclaringClass())) {
 			Class<?>[] types = method.getParameterTypes();
-			if ((types.length > 0) && "kotlin.coroutines.Continuation".equals(types[types.length - 1].getName())) {
+			if (types.length > 0 && "kotlin.coroutines.Continuation".equals(types[types.length - 1].getName())) {
 				return true;
 			}
 		}
diff --git a/spring-test/src/main/java/org/springframework/test/context/support/ContextLoaderUtils.java b/spring-test/src/main/java/org/springframework/test/context/support/ContextLoaderUtils.java
@@ -27,6 +27,7 @@
 import org.apache.commons.logging.LogFactory;
 
 import org.springframework.core.annotation.AnnotationUtils;
+import org.springframework.lang.Nullable;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.ContextConfigurationAttributes;
 import org.springframework.test.context.ContextHierarchy;
@@ -249,11 +250,11 @@ static List<ContextConfigurationAttributes> resolveContextConfigurationAttribute
 	}
 
 	private static void resolveContextConfigurationAttributes(List<ContextConfigurationAttributes> attributesList,
-			AnnotationDescriptor<ContextConfiguration> descriptor) {
+			@Nullable AnnotationDescriptor<ContextConfiguration> descriptor) {
 
 		if (descriptor != null) {
 			convertContextConfigToConfigAttributesAndAddToList(descriptor.synthesizeAnnotation(),
-				descriptor.getRootDeclaringClass(), attributesList);
+					descriptor.getRootDeclaringClass(), attributesList);
 			resolveContextConfigurationAttributes(attributesList, descriptor.next());
 		}
 	}
diff --git a/spring-test/src/main/java/org/springframework/test/context/transaction/TransactionalTestExecutionListener.java b/spring-test/src/main/java/org/springframework/test/context/transaction/TransactionalTestExecutionListener.java
@@ -163,6 +163,7 @@ protected TransactionAttribute findTransactionAttribute(Class<?> clazz) {
 			return findTransactionAttributeInEnclosingClassHierarchy(clazz);
 		}
 
+		@Nullable
 		private TransactionAttribute findTransactionAttributeInEnclosingClassHierarchy(Class<?> clazz) {
 			if (MetaAnnotationUtils.searchEnclosingClass(clazz)) {
 				return findTransactionAttribute(clazz.getEnclosingClass());
diff --git a/spring-test/src/main/java/org/springframework/test/context/web/WebTestContextBootstrapper.java b/spring-test/src/main/java/org/springframework/test/context/web/WebTestContextBootstrapper.java
@@ -16,6 +16,7 @@
 
 package org.springframework.test.context.web;
 
+import org.springframework.lang.Nullable;
 import org.springframework.test.context.ContextLoader;
 import org.springframework.test.context.MergedContextConfiguration;
 import org.springframework.test.context.TestContextBootstrapper;
@@ -70,6 +71,7 @@ protected MergedContextConfiguration processMergedContextConfiguration(MergedCon
 		}
 	}
 
+	@Nullable
 	private static WebAppConfiguration getWebAppConfiguration(Class<?> testClass) {
 		return MetaAnnotationUtils.findMergedAnnotation(testClass, WebAppConfiguration.class);
 	}
diff --git a/spring-web/src/main/java/org/springframework/http/codec/json/KotlinSerializationJsonDecoder.java b/spring-web/src/main/java/org/springframework/http/codec/json/KotlinSerializationJsonDecoder.java
@@ -31,6 +31,7 @@
 import org.springframework.core.codec.StringDecoder;
 import org.springframework.core.io.buffer.DataBuffer;
 import org.springframework.http.MediaType;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ConcurrentReferenceHashMap;
 import org.springframework.util.MimeType;
 
@@ -58,6 +59,7 @@ public class KotlinSerializationJsonDecoder extends AbstractDecoder<Object> {
 	// String decoding needed for now, see https://github.com/Kotlin/kotlinx.serialization/issues/204 for more details
 	private final StringDecoder stringDecoder = StringDecoder.allMimeTypes(StringDecoder.DEFAULT_DELIMITERS, false);
 
+
 	public KotlinSerializationJsonDecoder() {
 		this(Json.Default);
 	}
@@ -67,18 +69,23 @@ public KotlinSerializationJsonDecoder(Json json) {
 		this.json = json;
 	}
 
+
 	@Override
-	public boolean canDecode(ResolvableType elementType, MimeType mimeType) {
-		return super.canDecode(elementType, mimeType) && (!CharSequence.class.isAssignableFrom(elementType.toClass()));
+	public boolean canDecode(ResolvableType elementType, @Nullable MimeType mimeType) {
+		return (super.canDecode(elementType, mimeType) && !CharSequence.class.isAssignableFrom(elementType.toClass()));
 	}
 
 	@Override
-	public Flux<Object> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType, MimeType mimeType, Map<String, Object> hints) {
+	public Flux<Object> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
+
 		return Flux.error(new UnsupportedOperationException());
 	}
 
 	@Override
-	public Mono<Object> decodeToMono(Publisher<DataBuffer> inputStream, ResolvableType elementType, MimeType mimeType, Map<String, Object> hints) {
+	public Mono<Object> decodeToMono(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
+
 		return this.stringDecoder
 				.decodeToMono(inputStream, elementType, mimeType, hints)
 				.map(jsonText -> this.json.decodeFromString(serializer(elementType.getType()), jsonText));
@@ -100,4 +107,5 @@ private KSerializer<Object> serializer(Type type) {
 		}
 		return serializer;
 	}
+
 }
diff --git a/spring-web/src/main/java/org/springframework/http/codec/json/KotlinSerializationJsonEncoder.java b/spring-web/src/main/java/org/springframework/http/codec/json/KotlinSerializationJsonEncoder.java
@@ -34,6 +34,7 @@
 import org.springframework.core.io.buffer.DataBufferFactory;
 import org.springframework.http.MediaType;
 import org.springframework.http.codec.ServerSentEvent;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ConcurrentReferenceHashMap;
 import org.springframework.util.MimeType;
 
@@ -57,6 +58,7 @@ public class KotlinSerializationJsonEncoder extends AbstractEncoder<Object> {
 	// CharSequence encoding needed for now, see https://github.com/Kotlin/kotlinx.serialization/issues/204 for more details
 	private final CharSequenceEncoder charSequenceEncoder = CharSequenceEncoder.allMimeTypes();
 
+
 	public KotlinSerializationJsonEncoder() {
 		this(Json.Default);
 	}
@@ -66,15 +68,17 @@ public KotlinSerializationJsonEncoder(Json json) {
 		this.json = json;
 	}
 
+
 	@Override
-	public boolean canEncode(ResolvableType elementType, MimeType mimeType) {
-		return super.canEncode(elementType, mimeType)
-				&& (!String.class.isAssignableFrom(elementType.toClass()))
-				&& (!ServerSentEvent.class.isAssignableFrom(elementType.toClass()));
+	public boolean canEncode(ResolvableType elementType, @Nullable MimeType mimeType) {
+		return (super.canEncode(elementType, mimeType) && !String.class.isAssignableFrom(elementType.toClass()) &&
+				!ServerSentEvent.class.isAssignableFrom(elementType.toClass()));
 	}
 
 	@Override
-	public Flux<DataBuffer> encode(Publisher<?> inputStream, DataBufferFactory bufferFactory, ResolvableType elementType, MimeType mimeType, Map<String, Object> hints) {
+	public Flux<DataBuffer> encode(Publisher<?> inputStream, DataBufferFactory bufferFactory,
+			ResolvableType elementType, @Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
+
 		if (inputStream instanceof Mono) {
 			return Mono.from(inputStream)
 					.map(value -> encodeValue(value, bufferFactory, elementType, mimeType, hints))
@@ -90,7 +94,9 @@ public Flux<DataBuffer> encode(Publisher<?> inputStream, DataBufferFactory buffe
 	}
 
 	@Override
-	public DataBuffer encodeValue(Object value, DataBufferFactory bufferFactory, ResolvableType valueType, MimeType mimeType, Map<String, Object> hints) {
+	public DataBuffer encodeValue(Object value, DataBufferFactory bufferFactory,
+			ResolvableType valueType, @Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
+
 		String json = this.json.encodeToString(serializer(valueType.getType()), value);
 		return this.charSequenceEncoder.encodeValue(json, bufferFactory, valueType, mimeType, null);
 	}
@@ -111,4 +117,5 @@ private KSerializer<Object> serializer(Type type) {
 		}
 		return serializer;
 	}
+
 }
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ContinuationHandlerMethodArgumentResolver.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ContinuationHandlerMethodArgumentResolver.java
@@ -17,6 +17,7 @@
 package org.springframework.web.servlet.mvc.method.annotation;
 
 import org.springframework.core.MethodParameter;
+import org.springframework.lang.Nullable;
 import org.springframework.web.bind.support.WebDataBinderFactory;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.method.support.HandlerMethodArgumentResolver;
@@ -36,7 +37,10 @@ public boolean supportsParameter(MethodParameter parameter) {
 	}
 
 	@Override
-	public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
+	public Object resolveArgument(MethodParameter parameter, @Nullable ModelAndViewContainer mavContainer,
+			NativeWebRequest webRequest, @Nullable WebDataBinderFactory binderFactory) throws Exception {
+
 		return null;
 	}
+
 }

Original file line number	Diff line number	Diff line change
`@@ -27,6 +27,7 @@`
`27`	`27`	`import org.apache.commons.logging.LogFactory;`
`28`	`28`
`29`	`29`	`import org.springframework.core.annotation.AnnotationUtils;`
	`30`	`+import org.springframework.lang.Nullable;`
`30`	`31`	`import org.springframework.test.context.ContextConfiguration;`
`31`	`32`	`import org.springframework.test.context.ContextConfigurationAttributes;`
`32`	`33`	`import org.springframework.test.context.ContextHierarchy;`
`@@ -249,11 +250,11 @@ static List<ContextConfigurationAttributes> resolveContextConfigurationAttribute`
`249`	`250`	`}`
`250`	`251`
`251`	`252`	`private static void resolveContextConfigurationAttributes(List<ContextConfigurationAttributes> attributesList,`
`252`		`- AnnotationDescriptor<ContextConfiguration> descriptor) {`
	`253`	`+ @Nullable AnnotationDescriptor<ContextConfiguration> descriptor) {`
`253`	`254`
`254`	`255`	`if (descriptor != null) {`
`255`	`256`	`convertContextConfigToConfigAttributesAndAddToList(descriptor.synthesizeAnnotation(),`
`256`		`- descriptor.getRootDeclaringClass(), attributesList);`
	`257`	`+ descriptor.getRootDeclaringClass(), attributesList);`
`257`	`258`	`resolveContextConfigurationAttributes(attributesList, descriptor.next());`
`258`	`259`	`}`
`259`	`260`	`}`
Original file line number	Diff line number	Diff line change
`@@ -163,6 +163,7 @@ protected TransactionAttribute findTransactionAttribute(Class<?> clazz) {`
`163`	`163`	`return findTransactionAttributeInEnclosingClassHierarchy(clazz);`
`164`	`164`	`}`
`165`	`165`
	`166`	`+ @Nullable`
`166`	`167`	`private TransactionAttribute findTransactionAttributeInEnclosingClassHierarchy(Class<?> clazz) {`
`167`	`168`	`if (MetaAnnotationUtils.searchEnclosingClass(clazz)) {`
`168`	`169`	`return findTransactionAttribute(clazz.getEnclosingClass());`
Original file line number	Diff line number	Diff line change
`@@ -16,6 +16,7 @@`
`16`	`16`
`17`	`17`	`package org.springframework.test.context.web;`
`18`	`18`
	`19`	`+import org.springframework.lang.Nullable;`
`19`	`20`	`import org.springframework.test.context.ContextLoader;`
`20`	`21`	`import org.springframework.test.context.MergedContextConfiguration;`
`21`	`22`	`import org.springframework.test.context.TestContextBootstrapper;`
`@@ -70,6 +71,7 @@ protected MergedContextConfiguration processMergedContextConfiguration(MergedCon`
`70`	`71`	`}`
`71`	`72`	`}`
`72`	`73`
	`74`	`+ @Nullable`
`73`	`75`	`private static WebAppConfiguration getWebAppConfiguration(Class<?> testClass) {`
`74`	`76`	`return MetaAnnotationUtils.findMergedAnnotation(testClass, WebAppConfiguration.class);`
`75`	`77`	`}`
Original file line number	Diff line number	Diff line change
`@@ -17,6 +17,7 @@`
`17`	`17`	`package org.springframework.web.servlet.mvc.method.annotation;`
`18`	`18`
`19`	`19`	`import org.springframework.core.MethodParameter;`
	`20`	`+import org.springframework.lang.Nullable;`
`20`	`21`	`import org.springframework.web.bind.support.WebDataBinderFactory;`
`21`	`22`	`import org.springframework.web.context.request.NativeWebRequest;`
`22`	`23`	`import org.springframework.web.method.support.HandlerMethodArgumentResolver;`
`@@ -36,7 +37,10 @@ public boolean supportsParameter(MethodParameter parameter) {`
`36`	`37`	`}`
`37`	`38`
`38`	`39`	`@Override`
`39`		`- public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {`
	`40`	`+ public Object resolveArgument(MethodParameter parameter, @Nullable ModelAndViewContainer mavContainer,`
	`41`	`+ NativeWebRequest webRequest, @Nullable WebDataBinderFactory binderFactory) throws Exception {`
	`42`	`+`
`40`	`43`	`return null;`
`41`	`44`	`}`
	`45`	`+`
`42`	`46`	`}`