Java tutorial
/* * 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.lucene.util; import java.util.Collection; import java.util.Collections; /** * An object whose RAM usage can be computed. * * @lucene.internal */ public interface Accountable { /** * Return the memory usage of this object in bytes. Negative values are illegal. */ long ramBytesUsed(); /** * Returns nested resources of this class. * The result should be a point-in-time snapshot (to avoid race conditions). * @see Accountables */ default Collection<Accountable> getChildResources() { return Collections.emptyList(); } }