Flush APIedit

Flush Requestedit

A FlushRequest can be applied to one or more indices, or even on _all the indices:

FlushRequest request = new FlushRequest("index1"); 
FlushRequest requestMultiple = new FlushRequest("index1", "index2"); 
FlushRequest requestAll = new FlushRequest(); 

Flush one index

Flush multiple indices

Flush all the indices

Optional argumentsedit


Setting IndicesOptions controls how unavailable indices are resolved and how wildcard expressions are expanded


Set the wait_if_ongoing flag to true


Set the force flag to true

Synchronous Executionedit

FlushResponse flushResponse = client.indices().flush(request, RequestOptions.DEFAULT);

Asynchronous Executionedit

The asynchronous execution of a flush request requires both the FlushRequest instance and an ActionListener instance to be passed to the asynchronous method:

client.indices().flushAsync(request, RequestOptions.DEFAULT, listener); 

The FlushRequest to execute and the ActionListener to use when the execution completes

The asynchronous method does not block and returns immediately. Once it is completed the ActionListener is called back using the onResponse method if the execution successfully completed or using the onFailure method if it failed.

A typical listener for FlushResponse looks like:

ActionListener<FlushResponse> listener = new ActionListener<FlushResponse>() {
    public void onResponse(FlushResponse refreshResponse) {

    public void onFailure(Exception e) {

Called when the execution is successfully completed. The response is provided as an argument

Called in case of failure. The raised exception is provided as an argument

Flush Responseedit

The returned FlushResponse allows to retrieve information about the executed operation as follows:

int totalShards = flushResponse.getTotalShards(); 
int successfulShards = flushResponse.getSuccessfulShards(); 
int failedShards = flushResponse.getFailedShards(); 
DefaultShardOperationFailedException[] failures = flushResponse.getShardFailures(); 

Total number of shards hit by the flush request

Number of shards where the flush has succeeded

Number of shards where the flush has failed

A list of failures if the operation failed on one or more shards

By default, if the indices were not found, an ElasticsearchException will be thrown:

try {
    FlushRequest request = new FlushRequest("does_not_exist");
    client.indices().flush(request, RequestOptions.DEFAULT);
} catch (ElasticsearchException exception) {
    if (exception.status() == RestStatus.NOT_FOUND) {

Do something if the indices to be flushed were not found