Ensure that ServerStringMessageBodyHandler doesn't affect build time …

…resolution of builders

By making certain writers extend AllWriteableMessageBodyWriter we can be certain that even in the presense
of multiple writers, RESTEasy Reactive can optimize itself to use only the first one

Fixes: quarkusio#14720
(cherry picked from commit 2321d0c)

extensions/resteasy-reactive/quarkus-resteasy-reactive-jackson/runtime/src/main/java/io/quarkus/resteasy/reactive/jackson/runtime/serialisers/JacksonMessageBodyWriter.java

@@ -1,6 +1,6 @@
 package io.quarkus.resteasy.reactive.jackson.runtime.serialisers;
 
-import static org.jboss.resteasy.reactive.server.vertx.providers.serialisers.json.JsonMessageBodyWriterUtil.*;
+import static org.jboss.resteasy.reactive.server.vertx.providers.serialisers.json.JsonMessageBodyWriterUtil.setContentTypeIfNecessary;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -30,7 +30,7 @@
 
 import io.quarkus.resteasy.reactive.jackson.CustomSerialization;
 
-public class JacksonMessageBodyWriter implements ServerMessageBodyWriter<Object> {
+public class JacksonMessageBodyWriter extends ServerMessageBodyWriter.AllWriteableMessageBodyWriter {
 
     private static final String JSON_VIEW_NAME = JsonView.class.getName();
     private static final String CUSTOM_SERIALIZATION = CustomSerialization.class.getName();
@@ -62,11 +62,6 @@ private static void setNecessaryJsonFactoryConfig(JsonFactory jsonFactory) {
         jsonFactory.configure(Feature.FLUSH_PASSED_TO_STREAM, false);
     }
 
-    @Override
-    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
-        return true;
-    }
-
     @Override
     public void writeTo(Object o, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType,
             MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException, WebApplicationException {
@@ -87,11 +82,6 @@ public void writeTo(Object o, Class<?> type, Type genericType, Annotation[] anno
         }
     }
 
-    @Override
-    public boolean isWriteable(Class<?> type, Type genericType, ResteasyReactiveResourceInfo target, MediaType mediaType) {
-        return true;
-    }
-
     @Override
     public void writeResponse(Object o, Type genericType, ServerRequestContext context)
             throws WebApplicationException, IOException {

extensions/resteasy-reactive/quarkus-resteasy-reactive-jsonb/runtime/src/main/java/io/quarkus/resteasy/reactive/jsonb/runtime/serialisers/JsonbMessageBodyWriter.java

@@ -13,11 +13,10 @@
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.MultivaluedMap;
 
-import org.jboss.resteasy.reactive.server.spi.ResteasyReactiveResourceInfo;
 import org.jboss.resteasy.reactive.server.spi.ServerMessageBodyWriter;
 import org.jboss.resteasy.reactive.server.spi.ServerRequestContext;
 
-public class JsonbMessageBodyWriter implements ServerMessageBodyWriter<Object> {
+public class JsonbMessageBodyWriter extends ServerMessageBodyWriter.AllWriteableMessageBodyWriter {
 
     private final Jsonb json;
 
@@ -26,11 +25,6 @@ public JsonbMessageBodyWriter(Jsonb json) {
         this.json = json;
     }
 
-    @Override
-    public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType) {
-        return true;
-    }
-
     @Override
     public void writeTo(Object o, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType,
             MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException, WebApplicationException {
@@ -42,11 +36,6 @@ public void writeTo(Object o, Class<?> type, Type genericType, Annotation[] anno
         }
     }
 
-    @Override
-    public boolean isWriteable(Class<?> type, Type genericType, ResteasyReactiveResourceInfo target, MediaType mediaType) {
-        return true;
-    }
-
     @Override
     public void writeResponse(Object o, Type genericType, ServerRequestContext context)
             throws WebApplicationException, IOException {

independent-projects/resteasy-reactive/server/runtime/src/main/java/org/jboss/resteasy/reactive/server/core/startup/RuntimeResourceDeployment.java

@@ -294,9 +294,7 @@ public RuntimeResource buildResourceMethod(ResourceClass clazz,
                                     + "#" + method.getName() + "(" + Arrays.toString(method.getParameters()) + ")");
                             handlers.add(new VariableProducesHandler(serverMediaType, serialisers));
                             score.add(ScoreSystem.Category.Writer, ScoreSystem.Diagnostic.WriterRunTime);
-                        } else if (buildTimeWriters.size() == 1) {
-                            //only a single handler that can handle the response
-                            //this is a very common case
+                        } else if (isSingleEffectiveWriter(buildTimeWriters)) {
                             MessageBodyWriter<?> writer = buildTimeWriters.get(0);
                             handlers.add(new FixedProducesHandler(mediaType, new FixedEntityWriter(
                                     writer, serialisers)));
@@ -366,6 +364,16 @@ public RuntimeResource buildResourceMethod(ResourceClass clazz,
         return runtimeResource;
     }
 
+    private boolean isSingleEffectiveWriter(List<MessageBodyWriter<?>> buildTimeWriters) {
+        if (buildTimeWriters.size() == 1) { // common case of single writer
+            return true;
+        }
+
+        // in the case where the first Writer is an instance of AllWriteableMessageBodyWriter,
+        // it doesn't matter that we have multiple writers as the first one will always be used to serialize
+        return buildTimeWriters.get(0) instanceof ServerMessageBodyWriter.AllWriteableMessageBodyWriter;
+    }
+
     private void addHandlers(List<ServerRestHandler> handlers, ServerResourceMethod method, DeploymentInfo info,
             HandlerChainCustomizer.Phase phase) {
         for (HandlerChainCustomizer i : info.getGlobalHandlerCustomers()) {

independent-projects/resteasy-reactive/server/runtime/src/main/java/org/jboss/resteasy/reactive/server/spi/ServerMessageBodyWriter.java

@@ -1,6 +1,7 @@
 package org.jboss.resteasy.reactive.server.spi;
 
 import java.io.IOException;
+import java.lang.annotation.Annotation;
 import java.lang.reflect.Type;
 import javax.ws.rs.WebApplicationException;
 import javax.ws.rs.core.MediaType;
@@ -15,4 +16,24 @@ public interface ServerMessageBodyWriter<T> extends MessageBodyWriter<T> {
 
     void writeResponse(T o, Type genericType, ServerRequestContext context) throws WebApplicationException, IOException;
 
+    /**
+     * A special super-class of MessageBodyWriters that accepts all types of input.
+     * The main purpose of this class is to allow runtime code
+     * to optimize for the case when there are multiple providers determined at build time
+     * but the first one will always be used
+     */
+    abstract class AllWriteableMessageBodyWriter implements ServerMessageBodyWriter<Object> {
+
+        @Override
+        public final boolean isWriteable(Class<?> type, Type genericType, ResteasyReactiveResourceInfo target,
+                MediaType mediaType) {
+            return true;
+        }
+
+        @Override
+        public final boolean isWriteable(Class<?> type, Type genericType,
+                Annotation[] annotations, MediaType mediaType) {
+            return true;
+        }
+    }
 }