The percolator allows to register queries against an index, and then send percolate requests which include a doc, and getting back the queries that match on that doc out of the set of registered queries.

Read the main percolate documentation before reading this guide.

//This is the query we're registering in the percolator
QueryBuilder qb = termQuery("content", "amazing");

//Index the query = register it in the percolator
client.prepareIndex("_percolator", "myIndexName", "myDesignatedQueryName")
    .setRefresh(true) //Needed when the query shall be available immediately

This indexes the above term query under the name myDesignatedQueryName.

In order to check a document against the registered queries, use this code:

//Build a document to check against the percolator
XContentBuilder docBuilder = XContentFactory.jsonBuilder().startObject();
docBuilder.field("doc").startObject(); //This is needed to designate the document
docBuilder.field("content", "This is amazing!");
docBuilder.endObject(); //End of the doc field
docBuilder.endObject(); //End of the JSON root object
PercolateResponse response =
    client.preparePercolate("myIndexName", "myDocumentType").setSource(docBuilder).execute().actionGet();
//Iterate over the results
for(String result : response) {
    //Handle the result which is the name of
    //the query in the percolator