AutoRegistrationRuntimeWiringConfigurer refactoring

spring-graphql/src/main/java/org/springframework/graphql/data/query/AutoRegistrationRuntimeWiringConfigurer.java

@@ -17,7 +17,6 @@ package org.springframework.graphql.data.query;
 
 import java.util.List;
 import java.util.Map;
-import java.util.function.Function;
 import java.util.function.Predicate;
 
 import graphql.language.FieldDefinition;
@@ -49,19 +48,15 @@ class AutoRegistrationRuntimeWiringConfigurer implements RuntimeWiringConfigurer
 	private final static Log logger = LogFactory.getLog(AutoRegistrationRuntimeWiringConfigurer.class);
 
 
-	private final Map<String, Function<Boolean, DataFetcher<?>>> dataFetcherFactories;
+	private final Map<String, DataFetcherFactory> dataFetcherFactories;
 
 
 	/**
-	 * Constructor with a Map of GraphQL type names for which auto-registration
-	 * can be performed.
-	 * @param dataFetcherFactories Map with GraphQL type names as keys, and
-	 * functions to create a corresponding {@link DataFetcher} as values.
+	 * Constructor with a Map of GraphQL type names as keys, and
+	 * {@code DataFetcher} factories as values.
 	 */
-	AutoRegistrationRuntimeWiringConfigurer(
-			Map<String, Function<Boolean, DataFetcher<?>>> dataFetcherFactories) {
-
-		this.dataFetcherFactories = dataFetcherFactories;
+	AutoRegistrationRuntimeWiringConfigurer(Map<String, DataFetcherFactory> factories) {
+		this.dataFetcherFactories = factories;
 	}
 
 
@@ -75,6 +70,24 @@ class AutoRegistrationRuntimeWiringConfigurer implements RuntimeWiringConfigurer
 	}
 
 
+	/**
+	 * Callback interface to create the desired type of {@code DataFetcher}.
+	 */
+	interface DataFetcherFactory {
+
+		/**
+		 * Create a singe item {@code DataFetcher}.
+		 */
+		DataFetcher<?> single();
+
+		/**
+		 * Create {@code DataFetcher} for multiple items.
+		 */
+		DataFetcher<?> many();
+
+	}
+
+
 	private class AutoRegistrationWiringFactory implements WiringFactory {
 
 		private final RuntimeWiring.Builder builder;
@@ -112,16 +125,21 @@ class AutoRegistrationRuntimeWiringConfigurer implements RuntimeWiringConfigurer
 
 		@Nullable
 		private String getOutputTypeName(FieldWiringEnvironment environment) {
-			GraphQLType outputType = (environment.getFieldType() instanceof GraphQLList ?
-					((GraphQLList) environment.getFieldType()).getWrappedType() :
-					environment.getFieldType());
+			GraphQLType outputType = removeNonNullWrapper(environment.getFieldType());
 
-			if (outputType instanceof GraphQLNonNull) {
-				outputType = ((GraphQLNonNull) outputType).getWrappedType();
+			if (outputType instanceof GraphQLList) {
+				outputType = removeNonNullWrapper(((GraphQLList) outputType).getWrappedType());
 			}
 
-			return (outputType instanceof GraphQLNamedOutputType ?
-					((GraphQLNamedOutputType) outputType).getName() : null);
+			if (outputType instanceof GraphQLNamedOutputType namedType) {
+				return namedType.getName();
+			}
+
+			return null;
+		}
+
+		private GraphQLType removeNonNullWrapper(GraphQLType outputType) {
+			return (outputType instanceof GraphQLNonNull wrapper ? wrapper.getWrappedType() : outputType);
 		}
 
 		private boolean hasDataFetcherFor(FieldDefinition fieldDefinition) {
@@ -132,13 +150,11 @@ class AutoRegistrationRuntimeWiringConfigurer implements RuntimeWiringConfigurer
 			return this.existingQueryDataFetcherPredicate.test(fieldDefinition.getName());
 		}
 
-		private void logTraceMessage(
-				FieldWiringEnvironment environment, @Nullable String outputTypeName, boolean match) {
-
+		private void logTraceMessage(FieldWiringEnvironment environment, @Nullable String typeName, boolean match) {
 			if (logger.isTraceEnabled()) {
 				String query = environment.getFieldDefinition().getName();
 				logger.trace((match ? "Matched" : "Skipped") +
-						" output typeName " + (outputTypeName != null ? "'" + outputTypeName + "'" : "null") +
+						" output typeName " + (typeName != null ? "'" + typeName + "'" : "null") +
 						" for query '" + query + "'");
 			}
 		}
@@ -149,11 +165,16 @@ class AutoRegistrationRuntimeWiringConfigurer implements RuntimeWiringConfigurer
 			String outputTypeName = getOutputTypeName(environment);
 			logTraceMessage(environment, outputTypeName, true);
 
-			Function<Boolean, DataFetcher<?>> factory = dataFetcherFactories.get(outputTypeName);
+			DataFetcherFactory factory = dataFetcherFactories.get(outputTypeName);
 			Assert.notNull(factory, "Expected DataFetcher factory for typeName '" + outputTypeName + "'");
 
-			boolean single = !(environment.getFieldType() instanceof GraphQLList);
-			return factory.apply(single);
+			GraphQLType outputType = removeNonNullWrapper(environment.getFieldType());
+			if (outputType instanceof GraphQLList) {
+				return factory.many();
+			}
+			else {
+				return factory.single();
+			}
 		}
 
 	}

spring-graphql/src/main/java/org/springframework/graphql/data/query/QueryByExampleDataFetcher.java

@@ -42,6 +42,7 @@ import org.springframework.data.repository.query.ReactiveQueryByExampleExecutor;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.graphql.data.GraphQlArgumentBinder;
 import org.springframework.graphql.data.GraphQlRepository;
+import org.springframework.graphql.data.query.AutoRegistrationRuntimeWiringConfigurer.DataFetcherFactory;
 import org.springframework.graphql.execution.RuntimeWiringConfigurer;
 import org.springframework.graphql.execution.SelfDescribingDataFetcher;
 import org.springframework.lang.Nullable;
@@ -195,13 +196,23 @@ public abstract class QueryByExampleDataFetcher<T> {
 			List<QueryByExampleExecutor<?>> executors,
 			List<ReactiveQueryByExampleExecutor<?>> reactiveExecutors) {
 
-		Map<String, Function<Boolean, DataFetcher<?>>> factories = new HashMap<>();
+		Map<String, DataFetcherFactory> factories = new HashMap<>();
 
 		for (QueryByExampleExecutor<?> executor : executors) {
 			String typeName = RepositoryUtils.getGraphQlTypeName(executor);
 			if (typeName != null) {
 				Builder<?, ?> builder = customize(executor, builder(executor));
-				factories.put(typeName, single -> single ? builder.single() : builder.many());
+				factories.put(typeName, new DataFetcherFactory() {
+					@Override
+					public DataFetcher<?> single() {
+						return builder.single();
+					}
+
+					@Override
+					public DataFetcher<?> many() {
+						return builder.many();
+					}
+				});
 			}
 		}
 
@@ -209,7 +220,17 @@ public abstract class QueryByExampleDataFetcher<T> {
 			String typeName = RepositoryUtils.getGraphQlTypeName(executor);
 			if (typeName != null) {
 				ReactiveBuilder<?, ?> builder = customize(executor, builder(executor));
-				factories.put(typeName, single -> single ? builder.single() : builder.many());
+				factories.put(typeName, new DataFetcherFactory() {
+					@Override
+					public DataFetcher<?> single() {
+						return builder.single();
+					}
+
+					@Override
+					public DataFetcher<?> many() {
+						return builder.many();
+					}
+				});
 			}
 		}
 

spring-graphql/src/main/java/org/springframework/graphql/data/query/QuerydslDataFetcher.java

@@ -47,6 +47,7 @@ import org.springframework.data.repository.query.FluentQuery;
 import org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.graphql.data.GraphQlRepository;
+import org.springframework.graphql.data.query.AutoRegistrationRuntimeWiringConfigurer.DataFetcherFactory;
 import org.springframework.graphql.execution.RuntimeWiringConfigurer;
 import org.springframework.graphql.execution.SelfDescribingDataFetcher;
 import org.springframework.util.Assert;
@@ -219,13 +220,23 @@ public abstract class QuerydslDataFetcher<T> {
 			List<QuerydslPredicateExecutor<?>> executors,
 			List<ReactiveQuerydslPredicateExecutor<?>> reactiveExecutors) {
 
-		Map<String, Function<Boolean, DataFetcher<?>>> factories = new HashMap<>();
+		Map<String, DataFetcherFactory> factories = new HashMap<>();
 
 		for (QuerydslPredicateExecutor<?> executor : executors) {
 			String typeName = RepositoryUtils.getGraphQlTypeName(executor);
 			if (typeName != null) {
 				Builder builder = customize(executor, QuerydslDataFetcher.builder(executor).customizer(customizer(executor)));
-				factories.put(typeName, single -> single ? builder.single() : builder.many());
+				factories.put(typeName, new DataFetcherFactory() {
+					@Override
+					public DataFetcher<?> single() {
+						return builder.single();
+					}
+
+					@Override
+					public DataFetcher<?> many() {
+						return builder.many();
+					}
+				});
 			}
 		}
 
@@ -233,7 +244,17 @@ public abstract class QuerydslDataFetcher<T> {
 			String typeName = RepositoryUtils.getGraphQlTypeName(executor);
 			if (typeName != null) {
 				ReactiveBuilder builder = customize(executor, QuerydslDataFetcher.builder(executor).customizer(customizer(executor)));
-				factories.put(typeName, single -> single ? builder.single() : builder.many());
+				factories.put(typeName, new DataFetcherFactory() {
+					@Override
+					public DataFetcher<?> single() {
+						return builder.single();
+					}
+
+					@Override
+					public DataFetcher<?> many() {
+						return builder.many();
+					}
+				});
 			}
 		}