Refresh API

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Refresh Request

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

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

Refresh one index

Refresh multiple indices

Refresh all the indices

Optional arguments

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request.indicesOptions(IndicesOptions.lenientExpandOpen()); 

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

Synchronous Execution

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RefreshResponse refreshResponse = client.indices().refresh(request);

Asynchronous Execution

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

client.indices().refreshAsync(request, listener); 

The RefreshRequest 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 RefreshResponse looks like:

ActionListener<RefreshResponse> listener = new ActionListener<RefreshResponse>() {
    @Override
    public void onResponse(RefreshResponse refreshResponse) {
        
    }

    @Override
    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

Refresh Response

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

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

Total number of shards hit by the refresh request

Number of shards where the refresh has succeeded

Number of shards where the refresh 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 {
    RefreshRequest request = new RefreshRequest("does_not_exist");
    client.indices().refresh(request);
} catch (ElasticsearchException exception) {
    if (exception.status() == RestStatus.NOT_FOUND) {
        
    }
}

Do something if the indices to be refreshed were not found