Multi Term Vectors APIedit

Multi Term Vectors API allows to get multiple term vectors at once.

Multi Term Vectors Requestedit

There are two ways to create a MultiTermVectorsRequest.

The first way is to create an empty MultiTermVectorsRequest, and then add individual term vectors requests to it.

MultiTermVectorsRequest request = new MultiTermVectorsRequest(); 
TermVectorsRequest tvrequest1 =
    new TermVectorsRequest("authors", "1");
tvrequest1.setFields("user");
request.add(tvrequest1); 

XContentBuilder docBuilder = XContentFactory.jsonBuilder();
docBuilder.startObject().field("user", "guest-user").endObject();
TermVectorsRequest tvrequest2 =
    new TermVectorsRequest("authors", docBuilder);
request.add(tvrequest2); 

Create an empty MultiTermVectorsRequest.

Add the first TermVectorsRequest to the MultiTermVectorsRequest.

Add the second TermVectorsRequest for an artificial doc to the MultiTermVectorsRequest.

The second way can be used when all term vectors requests share the same arguments, such as index and other settings. In this case, a template TermVectorsRequest can be created with all necessary settings set, and this template request can be passed to MultiTermVectorsRequest along with all documents' ids for which to execute these requests.

TermVectorsRequest tvrequestTemplate =
    new TermVectorsRequest("authors", "fake_id"); 
tvrequestTemplate.setFields("user");
String[] ids = {"1", "2"};
MultiTermVectorsRequest request =
    new MultiTermVectorsRequest(ids, tvrequestTemplate); 

Create a template TermVectorsRequest.

Pass documents' ids and the template to the MultiTermVectorsRequest.

Synchronous executionedit

When executing a MultiTermVectorsRequest in the following manner, the client waits for the MultiTermVectorsResponse to be returned before continuing with code execution:

MultiTermVectorsResponse response =
    client.mtermvectors(request, RequestOptions.DEFAULT);

Synchronous calls may throw an IOException in case of either failing to parse the REST response in the high-level REST client, the request times out or similar cases where there is no response coming back from the server.

In cases where the server returns a 4xx or 5xx error code, the high-level client tries to parse the response body error details instead and then throws a generic ElasticsearchException and adds the original ResponseException as a suppressed exception to it.

Asynchronous executionedit

Executing a MultiTermVectorsRequest can also be done in an asynchronous fashion so that the client can return directly. Users need to specify how the response or potential failures will be handled by passing the request and a listener to the asynchronous multi-term-vectors method:

client.mtermvectorsAsync(
    request, RequestOptions.DEFAULT, listener); 

The MultiTermVectorsRequest 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. Failure scenarios and expected exceptions are the same as in the synchronous execution case.

A typical listener for multi-term-vectors looks like:

listener = new ActionListener<MultiTermVectorsResponse>() {
    @Override
    public void onResponse(MultiTermVectorsResponse mtvResponse) {
        
    }
    @Override
    public void onFailure(Exception e) {
        
    }
};

Called when the execution is successfully completed.

Called when the whole MultiTermVectorsRequest fails.

Multi Term Vectors Responseedit

MultiTermVectorsResponse allows to get the list of term vectors responses, each of which can be inspected as described in Term Vectors API.

List<TermVectorsResponse> tvresponseList =
    response.getTermVectorsResponses(); 
if (tvresponseList != null) {
    for (TermVectorsResponse tvresponse : tvresponseList) {
    }
}

Get a list of TermVectorsResponse