Polishing

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

@@ -130,10 +130,10 @@ public abstract class AbstractJacksonEncoder<T extends ObjectMapper> extends Jac
 		if (clazz == null) {
 			return true;
 		}
-		if (MappingJacksonValue.class.isAssignableFrom(elementType.resolve(clazz))) {
+		if (MappingJacksonValue.class.isAssignableFrom(clazz)) {
 			throw new UnsupportedOperationException("MappingJacksonValue is not supported, use hints instead");
 		}
-		return !String.class.isAssignableFrom(elementType.resolve(clazz));
+		return !String.class.isAssignableFrom(clazz);
 	}
 
 	@Override

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

@@ -77,10 +77,7 @@ public class GsonDecoder extends AbstractDataBufferDecoder<Object> {
 
 	@Override
 	public boolean canDecode(ResolvableType elementType, @Nullable MimeType mimeType) {
-		if (!super.canDecode(elementType, mimeType)) {
-			return false;
-		}
-		return !CharSequence.class.isAssignableFrom(elementType.toClass());
+		return super.canDecode(elementType, mimeType) && !CharSequence.class.isAssignableFrom(elementType.toClass());
 	}
 
 	@Override

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

@@ -106,8 +106,7 @@ public class GsonEncoder extends AbstractEncoder<Object> implements HttpMessageE
 		if (!super.canEncode(elementType, mimeType)) {
 			return false;
 		}
-		Class<?> clazz = elementType.toClass();
-		return !String.class.isAssignableFrom(elementType.resolve(clazz));
+		return !String.class.isAssignableFrom(elementType.toClass());
 	}
 
 	@Override

spring-webflux/src/main/java/org/springframework/web/reactive/result/method/annotation/AbstractMessageWriterResultHandler.java

@@ -267,9 +267,9 @@ public abstract class AbstractMessageWriterResultHandler extends HandlerResultHa
 
 	private List<MediaType> getMediaTypesFor(ResolvableType elementType) {
 		List<MediaType> writableMediaTypes = new ArrayList<>();
-		for (HttpMessageWriter<?> converter : getMessageWriters()) {
-			if (converter.canWrite(elementType, null)) {
-				writableMediaTypes.addAll(converter.getWritableMediaTypes(elementType));
+		for (HttpMessageWriter<?> messageWriter : getMessageWriters()) {
+			if (messageWriter.canWrite(elementType, null)) {
+				writableMediaTypes.addAll(messageWriter.getWritableMediaTypes(elementType));
 			}
 		}
 		return writableMediaTypes;