Update APIedit

You can either create an UpdateRequest and send it to the client:

UpdateRequest updateRequest = new UpdateRequest();
updateRequest.index("index");
updateRequest.type("_doc");
updateRequest.id("1");
updateRequest.doc(jsonBuilder()
        .startObject()
            .field("gender", "male")
        .endObject());
client.update(updateRequest).get();

Or you can use prepareUpdate() method:

client.prepareUpdate("ttl", "doc", "1")
        .setScript(new Script("ctx._source.gender = \"male\""  , ScriptService.ScriptType.INLINE, null, null))
        .get();

client.prepareUpdate("ttl", "doc", "1")
        .setDoc(jsonBuilder()               
            .startObject()
                .field("gender", "male")
            .endObject())
        .get();

Your script. It could also be a locally stored script name. In that case, you’ll need to use ScriptService.ScriptType.FILE

Document which will be merged to the existing one.

Note that you can’t provide both script and doc.

Update by scriptedit

The update API allows to update a document based on a script provided:

UpdateRequest updateRequest = new UpdateRequest("ttl", "doc", "1")
        .script(new Script("ctx._source.gender = \"male\""));
client.update(updateRequest).get();

Update by merging documentsedit

The update API also support passing a partial document, which will be merged into the existing document (simple recursive merge, inner merging of objects, replacing core "keys/values" and arrays). For example:

UpdateRequest updateRequest = new UpdateRequest("index", "type", "1")
        .doc(jsonBuilder()
            .startObject()
                .field("gender", "male")
            .endObject());
client.update(updateRequest).get();

Upsertedit

There is also support for upsert. If the document does not exist, the content of the upsert element will be used to index the fresh doc:

IndexRequest indexRequest = new IndexRequest("index", "type", "1")
        .source(jsonBuilder()
            .startObject()
                .field("name", "Joe Smith")
                .field("gender", "male")
            .endObject());
UpdateRequest updateRequest = new UpdateRequest("index", "type", "1")
        .doc(jsonBuilder()
            .startObject()
                .field("gender", "male")
            .endObject())
        .upsert(indexRequest);              
client.update(updateRequest).get();

If the document does not exist, the one in indexRequest will be added

If the document index/_doc/1 already exists, we will have after this operation a document like:

{
    "name"  : "Joe Dalton",
    "gender": "male"        
}

This field is added by the update request

If it does not exist, we will have a new document:

{
    "name" : "Joe Smith",
    "gender": "male"
}