Package com.google.api.gax.batching

Interface BatchingDescriptor<ElementT,ElementResultT,RequestT,ResponseT>

Type Parameters:

ElementT - The type of each individual element to be batched

ElementResultT - The type of the result for each individual element

RequestT - The type of the request that will contain the accumulated elements

ResponseT - The type of the response that will be unpacked into individual element results

@InternalApi("For google-cloud-java client use only.")
public interface BatchingDescriptor<ElementT,ElementResultT,RequestT,ResponseT>

An adapter that packs and unpacks the elements in and out of batch requests and responses.

This interface should be implemented by either a service specific client or autogenerated by gapic-generator.

Example implementation:

 class ListDescriptor implements BatchingDescriptor<String, String, List<String>, List<String>> {

   RequestBuilder<String, List<String>> newRequestBuilder(List<String> prototype) {
     return new RequestBuilder<String, List<String>>() {

       void add(String element) {
         list.add(element);
       }

       List<String> build() {
         return list.clone();
       }
     };
   }

   void splitResponse(List<String> callableResponse, List<SettableApiFuture<String>> batch) {
     for (int i = 0; i < batchResponse.size(); i++) {
       batch.get(i).set(batchResponse.get(i);
     }
   }

   void splitException(Throwable throwable, List<SettableApiFuture<String>> batch) {
     for (SettableApiFuture<String> result : batch) {
       result.setException(throwable);
     }
   }

   long countBytes(String element) {
     return element.length();
   }
 }
 

Method Summary

Modifier and Type	Method	Description
long	countBytes(ElementT element)	Returns the size of the passed element object in bytes.
default BatchResource	createEmptyResource()	Create an empty BatchResource.
default BatchResource	createResource(ElementT element)	Creates a new BatchResource with ElementT.
BatchingRequestBuilder<ElementT,RequestT>	newRequestBuilder(RequestT prototype)	Creates a new wrapper for the underlying request builder.
void	splitException(Throwable throwable, List<BatchEntry<ElementT,ElementResultT>> batch)	Unpacks the batch response error into individual element errors.
void	splitResponse(ResponseT batchResponse, List<BatchEntry<ElementT,ElementResultT>> batch)	Unpacks the batch response into individual elements results.

Method Details

newRequestBuilder

BatchingRequestBuilder<ElementT,RequestT> newRequestBuilder(RequestT prototype)

Creates a new wrapper for the underlying request builder. It's used to pack the current batch request with elements.

splitResponse

void splitResponse(ResponseT batchResponse,
 List<BatchEntry<ElementT,ElementResultT>> batch)

Unpacks the batch response into individual elements results.

splitException

void splitException(Throwable throwable,
 List<BatchEntry<ElementT,ElementResultT>> batch)

Unpacks the batch response error into individual element errors.

countBytes

long countBytes(ElementT element)

Returns the size of the passed element object in bytes.

createResource

default BatchResource createResource(ElementT element)

Creates a new BatchResource with ElementT.

createEmptyResource

default BatchResource createEmptyResource()

Create an empty BatchResource.