com.google.api.client.googleapis.batch

Class BatchRequest

java.lang.Object

com.google.api.client.googleapis.batch.BatchRequest

public final class BatchRequest
extends Object

An instance of this class represents a single batch of requests.

Sample use:

 // client is a AbstractGoogleClient (e.g.
 // com.google.api.services.books.Books)
 BatchRequest batch = client.batch(httpRequestInitializer);
 batch.queue(volumesList, Volumes.class, GoogleJsonErrorContainer.class,
     new BatchCallback<Volumes, GoogleJsonErrorContainer>() {

       public void onSuccess(Volumes volumes, HttpHeaders responseHeaders) {
         log("Success");
         printVolumes(volumes.getItems());
       }

       public void onFailure(GoogleJsonErrorContainer e, HttpHeaders responseHeaders) {
         log(e.getError().getMessage());
       }
     });
 batch.queue(volumesList, Volumes.class, GoogleJsonErrorContainer.class,
     new BatchCallback<Volumes, GoogleJsonErrorContainer>() {

       public void onSuccess(Volumes volumes, HttpHeaders responseHeaders) {
         log("Success");
         printVolumes(volumes.getItems());
       }

       public void onFailure(GoogleJsonErrorContainer e, HttpHeaders responseHeaders) {
         log(e.getError().getMessage());
       }
     });
 batch.execute();
 

The content of each individual response is stored in memory. There is thus a potential of encountering an OutOfMemoryError for very large responses.

Redirects are currently not followed in BatchRequest.

Implementation is not thread-safe.

Note: When setting an HttpUnsuccessfulResponseHandler by calling to HttpRequest.setUnsuccessfulResponseHandler(com.google.api.client.http.HttpUnsuccessfulResponseHandler), the handler is called for each unsuccessful part. As a result it's not recommended to use HttpBackOffUnsuccessfulResponseHandler on a batch request, since the back-off policy is invoked for each unsuccessful part.

Since:

1.9

Author:

rmistry@google.com (Ravi Mistry)

Constructor Summary

Constructors

Constructor and Description
BatchRequest(HttpTransport transport, HttpRequestInitializer httpRequestInitializer) Deprecated. Please use AbstractGoogleClient#batch(HttpRequestInitializer) to instantiate your batch request.

Method Summary

Modifier and Type	Method and Description
void	execute() Executes all queued HTTP requests in a single call, parses the responses and invokes callbacks.
GenericUrl	getBatchUrl() Returns the URL that will be hit when execute() is called.
Sleeper	getSleeper() Returns the sleeper.
<T,E> BatchRequest	queue(HttpRequest httpRequest, Class<T> dataClass, Class<E> errorClass, BatchCallback<T,E> callback) Queues the specified HttpRequest for batched execution.
BatchRequest	setBatchUrl(GenericUrl batchUrl) Sets the URL that will be hit when execute() is called.
BatchRequest	setSleeper(Sleeper sleeper) Sets the sleeper.
int	size() Returns the number of queued requests in this batch request.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BatchRequest

@Deprecated
public BatchRequest(HttpTransport transport,
                                HttpRequestInitializer httpRequestInitializer)

Deprecated. Please use AbstractGoogleClient#batch(HttpRequestInitializer) to instantiate your batch request.

Construct the BatchRequest.

Parameters:

transport - The transport to use for requests

httpRequestInitializer - The initializer to use when creating an HttpRequest or null for none

Method Detail

setBatchUrl

public BatchRequest setBatchUrl(GenericUrl batchUrl)

Sets the URL that will be hit when execute() is called. The default value is https://www.googleapis.com/batch.

getBatchUrl

public GenericUrl getBatchUrl()

Returns the URL that will be hit when execute() is called.

getSleeper

public Sleeper getSleeper()

Returns the sleeper.

Since:

1.15

setSleeper

public BatchRequest setSleeper(Sleeper sleeper)

Sets the sleeper. The default value is Sleeper.DEFAULT.

Since:

1.15

queue

public <T,E> BatchRequest queue(HttpRequest httpRequest,
                                Class<T> dataClass,
                                Class<E> errorClass,
                                BatchCallback<T,E> callback)
                         throws IOException

Queues the specified HttpRequest for batched execution. Batched requests are executed when execute() is called.

Type Parameters:

T - destination class type

E - error class type

Parameters:

httpRequest - HTTP Request

dataClass - Data class the response will be parsed into or Void.class to ignore the content

errorClass - Data class the unsuccessful response will be parsed into or Void.class to ignore the content

callback - Batch Callback

Returns:

this Batch request

Throws:

IOException - If building the HTTP Request fails

size

public int size()

Returns the number of queued requests in this batch request.

execute

public void execute()
             throws IOException

Executes all queued HTTP requests in a single call, parses the responses and invokes callbacks.

Calling execute() executes and clears the queued requests. This means that the BatchRequest object can be reused to queue(com.google.api.client.http.HttpRequest, java.lang.Class<T>, java.lang.Class<E>, com.google.api.client.googleapis.batch.BatchCallback<T, E>) and execute() requests again.

Throws:

IOException