Don't create object if no implicit members

codegen/src/main/java/software/amazon/awssdk/codegen/model/intermediate/ShapeModel.java

@@ -187,11 +187,17 @@ public List<MemberModel> getUnboundMembers() {
         List<MemberModel> unboundMembers = new ArrayList<>();
         if (members != null) {
             for (MemberModel member : members) {
-                if (member.getHttp().getLocation() == null) {
+                if (member.getHttp().getLocation() == null && !member.getHttp().getIsPayload()) {
                     if (hasPayloadMember) {
+                        // There is an explicit payload, but this unbound
+                        // member isn't it.
+                        // Note: Somewhat unintuitive, explicit payloads don't
+                        // have an explicit location; they're identified by
+                        // the payload HTTP trait being true.
                         throw new IllegalStateException(String.format(
-                                "C2J Shape %s has both an explicit payload member and unbound (no explicit location) members. "
-                                + "This is undefined behavior, verify the correctness of the C2J model", c2jName));
+                                "C2J Shape %s has both an explicit payload member and unbound (no explicit location) member, %s."
+                                + " This is undefined behavior, verify the correctness of the C2J model.",
+                                c2jName, member.getName()));
                     }
                     unboundMembers.add(member);
                 }
@@ -221,7 +227,12 @@ public List<MemberModel> getUnboundEventMembers() {
     public boolean hasPayloadMembers() {
         return hasPayloadMember ||
                getExplicitEventPayloadMember() != null ||
-               !getUnboundMembers().isEmpty() ||
+               hasImplicitPayloadMembers();
+
+    }
+
+    public boolean hasImplicitPayloadMembers() {
+        return !getUnboundMembers().isEmpty() ||
                (isEvent() && !getUnboundEventMembers().isEmpty());
     }
 

codegen/src/main/java/software/amazon/awssdk/codegen/poet/transform/protocols/JsonMarshallerSpec.java

@@ -95,6 +95,7 @@ protected FieldSpec operationInfoField() {
                                       .add(".httpMethod($T.$L)", SdkHttpMethod.class, shapeModel.getMarshaller().getVerb())
                                       .add(".hasExplicitPayloadMember($L)", shapeModel.isHasPayloadMember() ||
                                                                             shapeModel.getExplicitEventPayloadMember() != null)
+                                      .add(".hasImplicitPayloadMembers($L)", shapeModel.hasImplicitPayloadMembers())
                                       .add(".hasPayloadMembers($L)", shapeModel.hasPayloadMembers());
 
         if (StringUtils.isNotBlank(shapeModel.getMarshaller().getTarget())) {

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/alltypesrequestmarshaller.java

@@ -19,7 +19,8 @@
 @SdkInternalApi
 public class AllTypesRequestMarshaller implements Marshaller<AllTypesRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder().requestUri("/")
-                                                                            .httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false).hasPayloadMembers(true).build();
+            .httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false).hasImplicitPayloadMembers(true)
+            .hasPayloadMembers(true).build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -32,11 +33,10 @@ public SdkHttpFullRequest marshall(AllTypesRequest allTypesRequest) {
         Validate.paramNotNull(allTypesRequest, "allTypesRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(allTypesRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();
         }
     }
 }
-

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/eventstreamoperationrequestmarshaller.java

@@ -19,8 +19,8 @@
 @SdkInternalApi
 public class EventStreamOperationRequestMarshaller implements Marshaller<EventStreamOperationRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder()
-                                                                            .requestUri("/2016-03-11/eventStreamOperation").httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(true)
-                                                                            .hasPayloadMembers(true).hasEventStreamingInput(true).build();
+            .requestUri("/2016-03-11/eventStreamOperation").httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(true)
+            .hasImplicitPayloadMembers(false).hasPayloadMembers(true).hasEventStreamingInput(true).build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -33,7 +33,7 @@ public SdkHttpFullRequest marshall(EventStreamOperationRequest eventStreamOperat
         Validate.paramNotNull(eventStreamOperationRequest, "eventStreamOperationRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(eventStreamOperationRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/eventstreamoperationwithonlyinputrequestmarshaller.java

@@ -17,11 +17,11 @@
  */
 @Generated("software.amazon.awssdk:codegen")
 @SdkInternalApi
-public class EventStreamOperationWithOnlyInputRequestMarshaller implements
-                                                                Marshaller<EventStreamOperationWithOnlyInputRequest> {
+public class EventStreamOperationWithOnlyInputRequestMarshaller implements Marshaller<EventStreamOperationWithOnlyInputRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder()
-                                                                            .requestUri("/2016-03-11/EventStreamOperationWithOnlyInput").httpMethod(SdkHttpMethod.POST)
-                                                                            .hasExplicitPayloadMember(false).hasPayloadMembers(true).hasEventStreamingInput(true).build();
+            .requestUri("/2016-03-11/EventStreamOperationWithOnlyInput").httpMethod(SdkHttpMethod.POST)
+            .hasExplicitPayloadMember(false).hasImplicitPayloadMembers(true).hasPayloadMembers(true).hasEventStreamingInput(true)
+            .build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -34,11 +34,10 @@ public SdkHttpFullRequest marshall(EventStreamOperationWithOnlyInputRequest even
         Validate.paramNotNull(eventStreamOperationWithOnlyInputRequest, "eventStreamOperationWithOnlyInputRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(eventStreamOperationWithOnlyInputRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();
         }
     }
 }
-

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/nestedcontainersrequestmarshaller.java

@@ -19,7 +19,8 @@
 @SdkInternalApi
 public class NestedContainersRequestMarshaller implements Marshaller<NestedContainersRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder().requestUri("/")
-                                                                            .httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false).hasPayloadMembers(true).build();
+            .httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false).hasImplicitPayloadMembers(true)
+            .hasPayloadMembers(true).build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -32,11 +33,10 @@ public SdkHttpFullRequest marshall(NestedContainersRequest nestedContainersReque
         Validate.paramNotNull(nestedContainersRequest, "nestedContainersRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(nestedContainersRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();
         }
     }
 }
-

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/operationwithnoinputoroutputrequestmarshaller.java

@@ -17,10 +17,10 @@
  */
 @Generated("software.amazon.awssdk:codegen")
 @SdkInternalApi
-public class OperationWithNoInputOrOutputRequestMarshaller implements
-                                                           Marshaller<OperationWithNoInputOrOutputRequest> {
+public class OperationWithNoInputOrOutputRequestMarshaller implements Marshaller<OperationWithNoInputOrOutputRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder().requestUri("/")
-                                                                            .httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false).hasPayloadMembers(false).build();
+            .httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false).hasImplicitPayloadMembers(false)
+            .hasPayloadMembers(false).build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -33,11 +33,10 @@ public SdkHttpFullRequest marshall(OperationWithNoInputOrOutputRequest operation
         Validate.paramNotNull(operationWithNoInputOrOutputRequest, "operationWithNoInputOrOutputRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(operationWithNoInputOrOutputRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();
         }
     }
 }
-

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/streaminginputoperationrequestmarshaller.java

@@ -19,8 +19,8 @@
 @SdkInternalApi
 public class StreamingInputOperationRequestMarshaller implements Marshaller<StreamingInputOperationRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder()
-                                                                            .requestUri("/2016-03-11/streamingInputOperation").httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(true)
-                                                                            .hasPayloadMembers(true).hasStreamingInput(true).build();
+            .requestUri("/2016-03-11/streamingInputOperation").httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(true)
+            .hasImplicitPayloadMembers(false).hasPayloadMembers(true).hasStreamingInput(true).build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -33,11 +33,10 @@ public SdkHttpFullRequest marshall(StreamingInputOperationRequest streamingInput
         Validate.paramNotNull(streamingInputOperationRequest, "streamingInputOperationRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(streamingInputOperationRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();
         }
     }
 }
-

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/transform/streamingoutputoperationrequestmarshaller.java

@@ -19,8 +19,8 @@
 @SdkInternalApi
 public class StreamingOutputOperationRequestMarshaller implements Marshaller<StreamingOutputOperationRequest> {
     private static final OperationInfo SDK_OPERATION_BINDING = OperationInfo.builder()
-                                                                            .requestUri("/2016-03-11/streamingOutputOperation").httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false)
-                                                                            .hasPayloadMembers(false).build();
+            .requestUri("/2016-03-11/streamingOutputOperation").httpMethod(SdkHttpMethod.POST).hasExplicitPayloadMember(false)
+            .hasImplicitPayloadMembers(false).hasPayloadMembers(false).build();
 
     private final BaseAwsJsonProtocolFactory protocolFactory;
 
@@ -33,11 +33,10 @@ public SdkHttpFullRequest marshall(StreamingOutputOperationRequest streamingOutp
         Validate.paramNotNull(streamingOutputOperationRequest, "streamingOutputOperationRequest");
         try {
             ProtocolMarshaller<SdkHttpFullRequest> protocolMarshaller = protocolFactory
-                .createProtocolMarshaller(SDK_OPERATION_BINDING);
+                    .createProtocolMarshaller(SDK_OPERATION_BINDING);
             return protocolMarshaller.marshall(streamingOutputOperationRequest);
         } catch (Exception e) {
             throw SdkClientException.builder().message("Unable to marshall request to JSON: " + e.getMessage()).cause(e).build();
         }
     }
 }
-

core/protocols/aws-json-protocol/src/main/java/software/amazon/awssdk/protocols/json/internal/marshall/JsonProtocolMarshaller.java

@@ -62,6 +62,7 @@ public class JsonProtocolMarshaller implements ProtocolMarshaller<SdkHttpFullReq
     private final String contentType;
     private final AwsJsonProtocolMetadata protocolMetadata;
     private final boolean hasExplicitPayloadMember;
+    private final boolean hasImplicitPayloadMembers;
     private final boolean hasStreamingInput;
 
     private final JsonMarshallerContext marshallerContext;
@@ -78,6 +79,7 @@ public class JsonProtocolMarshaller implements ProtocolMarshaller<SdkHttpFullReq
         this.contentType = contentType;
         this.protocolMetadata = protocolMetadata;
         this.hasExplicitPayloadMember = operationInfo.hasExplicitPayloadMember();
+        this.hasImplicitPayloadMembers = operationInfo.hasImplicitPayloadMembers();
         this.hasStreamingInput = operationInfo.hasStreamingInput();
         this.hasEventStreamingInput = operationInfo.hasEventStreamingInput();
         this.hasEvent = operationInfo.hasEvent();
@@ -167,7 +169,8 @@ private SdkHttpFullRequest.Builder fillBasicRequestParams(OperationInfo operatio
      * members bound to the payload will be added as fields to this object.
      */
     private void startMarshalling() {
-        if (!hasExplicitPayloadMember) {
+        // Create the implicit request object if needed.
+        if (needTopLevelJsonObject()) {
             jsonGenerator.writeStartObject();
         }
     }
@@ -220,7 +223,7 @@ private SdkHttpFullRequest finishMarshalling() {
         // Content may already be set if the payload is binary data.
         if (request.contentStreamProvider() == null) {
             // End the implicit request object if needed.
-            if (!hasExplicitPayloadMember) {
+            if (needTopLevelJsonObject()) {
                 jsonGenerator.writeEndObject();
             }
 
@@ -263,4 +266,10 @@ private void marshallField(SdkField<?> field, Object val) {
         MARSHALLER_REGISTRY.getMarshaller(field.location(), field.marshallingType(), val)
                            .marshall(val, marshallerContext, field.locationName(), (SdkField<Object>) field);
     }
+
+    private boolean needTopLevelJsonObject() {
+        return AwsJsonProtocol.AWS_JSON.equals(protocolMetadata.protocol())
+               || (!hasExplicitPayloadMember && hasImplicitPayloadMembers);
+
+    }
 }

core/protocols/protocol-core/src/main/java/software/amazon/awssdk/protocols/core/OperationInfo.java

@@ -31,6 +31,7 @@ public final class OperationInfo {
     private final String apiVersion;
     private final boolean hasExplicitPayloadMember;
     private final boolean hasPayloadMembers;
+    private final boolean hasImplicitPayloadMembers;
     private final boolean hasStreamingInput;
     private final boolean hasEventStreamingInput;
     private final boolean hasEvent;
@@ -42,6 +43,7 @@ private OperationInfo(Builder builder) {
         this.operationIdentifier = builder.operationIdentifier;
         this.apiVersion = builder.apiVersion;
         this.hasExplicitPayloadMember = builder.hasExplicitPayloadMember;
+        this.hasImplicitPayloadMembers = builder.hasImplicitPayloadMembers;
         this.hasPayloadMembers = builder.hasPayloadMembers;
         this.hasStreamingInput = builder.hasStreamingInput;
         this.additionalMetadata = builder.additionalMetadata.build();
@@ -95,6 +97,14 @@ public boolean hasPayloadMembers() {
         return hasPayloadMembers;
     }
 
+    /**
+     * @return True if the operation has members that are not explicitly bound to a marshalling location, and thus are
+     * implicitly bound to the body.
+     */
+    public boolean hasImplicitPayloadMembers() {
+        return hasImplicitPayloadMembers;
+    }
+
     /**
      * @return True if the operation has streaming input.
      */
@@ -144,6 +154,7 @@ public static final class Builder {
         private String operationIdentifier;
         private String apiVersion;
         private boolean hasExplicitPayloadMember;
+        private boolean hasImplicitPayloadMembers;
         private boolean hasPayloadMembers;
         private boolean hasStreamingInput;
         private boolean hasEventStreamingInput;
@@ -183,6 +194,11 @@ public Builder hasPayloadMembers(boolean hasPayloadMembers) {
             return this;
         }
 
+        public Builder hasImplicitPayloadMembers(boolean hasImplicitPayloadMembers) {
+            this.hasImplicitPayloadMembers = hasImplicitPayloadMembers;
+            return this;
+        }
+
         public Builder hasStreamingInput(boolean hasStreamingInput) {
             this.hasStreamingInput = hasStreamingInput;
             return this;

test/protocol-tests-core/src/main/resources/software/amazon/awssdk/protocol/suites/cases/rest-json-contenttype.json

@@ -219,6 +219,60 @@
     }
   }
 },
+{
+  "description": "NoPayloadGet",
+  "given": {
+    "input": {
+    }
+  },
+  "when": {
+    "action": "marshall",
+    "operation": "NoPayloadPost"
+  },
+  "then": {
+    "serializedAs": {
+      "uri": "/no-payload",
+      "method": "POST",
+      "headers": {
+        "doesNotContain": [
+          "Content-Type"
+        ]
+      },
+      "body": {
+        "equals": ""
+      }
+    }
+  }
+},
+{
+  "description": "NoPayloadGetWithHeader",
+  "given": {
+    "input": {
+      "testId": "t-12345"
+    }
+  },
+  "when": {
+    "action": "marshall",
+    "operation": "NoPayloadPost"
+  },
+  "then": {
+    "serializedAs": {
+      "uri": "/no-payload",
+      "method": "POST",
+      "headers": {
+        "contains": {
+          "x-amz-test-id": "t-12345"
+        },
+        "doesNotContain": [
+          "Content-Type"
+        ]
+      },
+      "body": {
+        "equals": ""
+      }
+    }
+  }
+},
 {
   "description": "TestBodyNoParams",
   "given": {