Polishing contribution

Closes gh-30192

Author: rstoyanchev

spring-core/src/main/java/org/springframework/util/MimeType.java

@@ -269,7 +269,7 @@ public boolean isWildcardType() {
 	 */
 	public boolean isWildcardSubtype() {
 		String subtype = getSubtype();
-		return WILDCARD_TYPE.equals(subtype) || subtype.startsWith("*+");
+		return (WILDCARD_TYPE.equals(subtype) || subtype.startsWith("*+"));
 	}
 
 	/**

spring-web/src/main/java/org/springframework/http/codec/FormHttpMessageReader.java

@@ -104,14 +104,17 @@ public int getMaxInMemorySize() {
 
 	@Override
 	public boolean canRead(ResolvableType elementType, @Nullable MediaType mediaType) {
-		if (mediaType == null || MediaType.APPLICATION_FORM_URLENCODED.isCompatibleWith(mediaType)) {
-			if (MultiValueMap.class.isAssignableFrom(elementType.toClass()) &&
-					elementType.hasUnresolvableGenerics()) {
-				return true;
-			}
-			return MULTIVALUE_STRINGS_TYPE.isAssignableFrom(elementType);
+		if (!supportsMediaType(mediaType)) {
+			return false;
+		}
+		if (MultiValueMap.class.isAssignableFrom(elementType.toClass()) && elementType.hasUnresolvableGenerics()) {
+			return true;
 		}
-		return false;
+		return MULTIVALUE_STRINGS_TYPE.isAssignableFrom(elementType);
+	}
+
+	private static boolean supportsMediaType(@Nullable MediaType mediaType) {
+		return (mediaType == null || MediaType.APPLICATION_FORM_URLENCODED.isCompatibleWith(mediaType));
 	}
 
 	@Override

spring-web/src/main/java/org/springframework/http/codec/json/AbstractJackson2Decoder.java

@@ -97,14 +97,16 @@ public int getMaxInMemorySize() {
 
 	@Override
 	public boolean canDecode(ResolvableType elementType, @Nullable MimeType mimeType) {
-		// Skip String: CharSequenceDecoder + "*/*" comes after
-		if (CharSequence.class.isAssignableFrom(elementType.toClass()) || !supportsMimeType(mimeType)) {
+		if (!supportsMimeType(mimeType)) {
 			return false;
 		}
 		ObjectMapper mapper = selectObjectMapper(elementType, mimeType);
 		if (mapper == null) {
 			return false;
 		}
+		if (CharSequence.class.isAssignableFrom(elementType.toClass())) {
+			return false;
+		}
 		JavaType javaType = mapper.constructType(elementType.getType());
 		if (!logger.isDebugEnabled()) {
 			return mapper.canDeserialize(javaType);

spring-web/src/main/java/org/springframework/http/codec/multipart/MultipartHttpMessageReader.java

@@ -81,6 +81,11 @@ public List<MediaType> getReadableMediaTypes() {
 		return MIME_TYPES;
 	}
 
+	@Override
+	public boolean canRead(ResolvableType elementType, @Nullable MediaType mediaType) {
+		return supportsMediaType(mediaType) && MULTIPART_VALUE_TYPE.isAssignableFrom(elementType);
+	}
+
 	private boolean supportsMediaType(@Nullable MediaType mediaType) {
 		if (mediaType == null) {
 			return true;
@@ -93,12 +98,6 @@ private boolean supportsMediaType(@Nullable MediaType mediaType) {
 		return false;
 	}
 
-	@Override
-	public boolean canRead(ResolvableType elementType, @Nullable MediaType mediaType) {
-		return supportsMediaType(mediaType) && MULTIPART_VALUE_TYPE.isAssignableFrom(elementType);
-	}
-
-
 	@Override
 	public Flux<MultiValueMap<String, Part>> read(ResolvableType elementType,
 			ReactiveHttpInputMessage message, Map<String, Object> hints) {