processing/src/main/java/org/apache/druid/query/topn/TopNQueryMetricsFactory.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.druid.query.topn;

/**
 * Implementations could be injected using
 *
 * PolyBind
 *    .optionBinder(binder, Key.get(TopNQueryMetricsFactory.class))
 *    .addBinding("myCustomTopNQueryMetricsFactory")
 *    .to(MyCustomTopNQueryMetricsFactory.class);
 *
 * And then setting property:
 * druid.query.topN.queryMetricsFactory=myCustomTopNQueryMetricsFactory
 */
public interface TopNQueryMetricsFactory
{

  TopNQueryMetrics makeMetrics();
}