Inject prepared GraphqlErrorBuilder in error handling methods

Prior to this commit, error handling methods would support various
arguments, including the exception being handled.
Our reference documentation would advise to create a new instance of a
`GraphQLError` using `GraphQLError.newError()`. This does not initialize
the location and path information of the current error.

This commit allows error handling methods to get injected with a
`GraphQlErrorBuilder<?>` argument that is initialized with the current
`DataFetchingEnvironment` (thus filling the location and path parts).

Fixes gh-1200

spring-graphql-docs/src/main/java/org/springframework/graphql/docs/controllers/exceptionhandler/Book.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2020-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.graphql.docs.controllers.exceptionhandler;
+
+public record Book() {
+}

spring-graphql-docs/src/main/java/org/springframework/graphql/docs/controllers/exceptionhandler/BookController.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2020-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.graphql.docs.controllers.exceptionhandler;
+
+
+import graphql.GraphQLError;
+import graphql.GraphqlErrorBuilder;
+
+import org.springframework.graphql.data.method.annotation.Argument;
+import org.springframework.graphql.data.method.annotation.GraphQlExceptionHandler;
+import org.springframework.graphql.data.method.annotation.QueryMapping;
+import org.springframework.graphql.execution.ErrorType;
+import org.springframework.stereotype.Controller;
+import org.springframework.validation.BindException;
+
+@Controller
+public class BookController {
+
+	@QueryMapping
+	public Book bookById(@Argument Long id) {
+		return /**/ new Book();
+	}
+
+	@GraphQlExceptionHandler
+	public GraphQLError handle(GraphqlErrorBuilder<?> errorBuilder, BindException ex) {
+		return errorBuilder
+				.errorType(ErrorType.BAD_REQUEST)
+				.message(ex.getMessage())
+				.build();
+	}
+
+}

spring-graphql-docs/src/main/java/org/springframework/graphql/docs/controllers/exceptionhandler/GlobalExceptionHandler.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2020-2025 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.graphql.docs.controllers.exceptionhandler;
+
+import graphql.GraphQLError;
+import graphql.GraphqlErrorBuilder;
+
+import org.springframework.graphql.data.method.annotation.GraphQlExceptionHandler;
+import org.springframework.graphql.execution.ErrorType;
+import org.springframework.validation.BindException;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+
+@ControllerAdvice
+public class GlobalExceptionHandler {
+
+	@GraphQlExceptionHandler
+	public GraphQLError handle(GraphqlErrorBuilder<?> errorBuilder, BindException ex) {
+		return errorBuilder
+				.errorType(ErrorType.BAD_REQUEST)
+				.message(ex.getMessage())
+				.build();
+	}
+
+}