diff --git a/spring-graphql-common/src/main/java/org/springframework/graphql/DefaultGraphQLInterceptor.java b/spring-graphql-common/src/main/java/org/springframework/graphql/DefaultGraphQLInterceptor.java
index 188d5212..15c1bed8 100644
--- a/spring-graphql-common/src/main/java/org/springframework/graphql/DefaultGraphQLInterceptor.java
+++ b/spring-graphql-common/src/main/java/org/springframework/graphql/DefaultGraphQLInterceptor.java
@@ -1,24 +1,5 @@
 package org.springframework.graphql;
 
-import graphql.ExecutionInput;
-import graphql.ExecutionResult;
-import org.springframework.http.HttpHeaders;
-import reactor.core.publisher.Mono;
-
 public class DefaultGraphQLInterceptor implements GraphQLInterceptor {
 
-    @Override
-    public Mono<ExecutionInput> preHandle(ExecutionInput input, HttpHeaders headers) {
-        return Mono.just(input);
-    }
-
-    @Override
-    public Mono<ExecutionResult> postHandle(ExecutionResult result, HttpHeaders httpHeaders) {
-        return Mono.just(result);
-    }
-
-    @Override
-    public Mono<GraphQLResponseBody> customizeResponseBody(GraphQLResponseBody graphQLResponseBody, ExecutionResult executionResult, HttpHeaders httpHeader) {
-        return Mono.just(graphQLResponseBody);
-    }
 }
\ No newline at end of file
diff --git a/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLHandler.java b/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLHandler.java
index 8d5e4c74..68fedac6 100644
--- a/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLHandler.java
+++ b/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLHandler.java
@@ -21,9 +21,6 @@ public class GraphQLHandler {
 
     public Mono<GraphQLResponseBody> graphqlPOST(GraphQLRequestBody body, HttpHeaders httpHeaders) {
         String query = body.getQuery();
-        if (query == null) {
-            query = "";
-        }
         ExecutionInput input = ExecutionInput.newExecutionInput()
                 .query(query)
                 .operationName(body.getOperationName())
diff --git a/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLInterceptor.java b/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLInterceptor.java
index 3b111e93..d23ccd86 100644
--- a/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLInterceptor.java
+++ b/spring-graphql-common/src/main/java/org/springframework/graphql/GraphQLInterceptor.java
@@ -7,10 +7,16 @@ import reactor.core.publisher.Mono;
 
 public interface GraphQLInterceptor {
 
-    Mono<ExecutionInput> preHandle(ExecutionInput input, HttpHeaders headers);
+    default Mono<ExecutionInput> preHandle(ExecutionInput input, HttpHeaders headers) {
+        return Mono.just(input);
+    }
 
-    Mono<ExecutionResult> postHandle(ExecutionResult result, HttpHeaders httpHeaders);
+    default Mono<ExecutionResult> postHandle(ExecutionResult result, HttpHeaders httpHeaders) {
+        return Mono.just(result);
+    }
 
-    Mono<GraphQLResponseBody> customizeResponseBody(GraphQLResponseBody graphQLResponseBody, ExecutionResult executionResult, HttpHeaders httpHeader);
+    default Mono<GraphQLResponseBody> customizeResponseBody(GraphQLResponseBody graphQLResponseBody, ExecutionResult executionResult, HttpHeaders httpHeader) {
+        return Mono.just(graphQLResponseBody);
+    }
 
 }
\ No newline at end of file