Allow mapping annotations at the class level

Closes gh-195

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/MutationMapping.java

@@ -24,15 +24,18 @@ import java.lang.annotation.Target;
 import org.springframework.core.annotation.AliasFor;
 
 /**
- * Annotation to express a mapping to a GraphQL Mutation operation.
+ * {@code @MutationMapping} is a <em>composed annotation</em> that acts as a
+ * shortcut for {@link SchemaMapping @SchemaMapping} with
+ * {@code typeName="Mutation"}.
  *
- * <p>Specifically, {@code @MutationMapping} is a <em>composed annotation</em> that
- * acts as a shortcut for {@code @SchemaMapping(typeName = "Mutation")}.
+ * <p>You can use this annotation both at the method and at the class level, in
+ * which case all handlers methods in the controller are mutations, unless the
+ * typeName is overridden.
  *
  * @author Rossen Stoyanchev
  * @since 1.0.0
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.TYPE, ElementType.METHOD})
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 @SchemaMapping(typeName = "Mutation")

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/QueryMapping.java

@@ -24,15 +24,18 @@ import java.lang.annotation.Target;
 import org.springframework.core.annotation.AliasFor;
 
 /**
- * Annotation to express a mapping to a GraphQL Query operation.
+ * {@code @QueryMapping} is a <em>composed annotation</em> that acts as a
+ * shortcut for {@link SchemaMapping @SchemaMapping} with
+ * {@code typeName="Query"}.
  *
- * <p>Specifically, {@code @QueryMapping} is a <em>composed annotation</em> that
- * acts as a shortcut for {@code @SchemaMapping(typeName = "Query")}.
+ * <p>You can use this annotation both at the method and at the class level, in
+ * which case all handlers methods in the controller are queries, unless the
+ * typeName is overridden.
  *
  * @author Rossen Stoyanchev
  * @since 1.0.0
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.TYPE, ElementType.METHOD})
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 @SchemaMapping(typeName = "Query")

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/SchemaMapping.java

@@ -26,9 +26,12 @@ import graphql.schema.DataFetchingEnvironment;
 import org.springframework.core.annotation.AliasFor;
 
 /**
- * Annotation to express a mapping to a GraphQL type and field pair. Typically
- * used on methods, but also possible to use at the class level to specify a
- * default type name for all handler methods.
+ * Annotation to express the mapping of a handler method to a GraphQL type and
+ * field pair.
+ *
+ * <p>You can use this annotation both at the method and at the class level, in
+ * which case all handlers methods inherit the class-level typeName by default
+ * unless overridden at the method level.
  *
  * @author Rossen Stoyanchev
  * @since 1.0.0

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/SubscriptionMapping.java

@@ -24,15 +24,18 @@ import java.lang.annotation.Target;
 import org.springframework.core.annotation.AliasFor;
 
 /**
- * Annotation to express a mapping to a GraphQL Subscription operation.
+ * {@code @SubscriptionMapping} is a <em>composed annotation</em> that acts as a
+ * shortcut for {@link SchemaMapping @SchemaMapping} with
+ * {@code typeName="Subscription"}.
  *
- * <p>Specifically, {@code @QueryMapping} is a <em>composed annotation</em> that
- * acts as a shortcut for {@code @SchemaMapping(typeName = "Subscription")}.
+ * <p>You can use this annotation both at the method and at the class level, in
+ * which case all handlers methods in the controller are subscriptions, unless the
+ * typeName is overridden.
  *
  * @author Rossen Stoyanchev
  * @since 1.0.0
  */
-@Target(ElementType.METHOD)
+@Target({ElementType.TYPE, ElementType.METHOD})
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 @SchemaMapping(typeName = "Subscription")