1 /* 2 * Copyright 2013 The Netty Project 3 * 4 * The Netty Project licenses this file to you under the Apache License, 5 * version 2.0 (the "License"); you may not use this file except in compliance 6 * with the License. You may obtain a copy of the License at: 7 * 8 * https://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 13 * License for the specific language governing permissions and limitations 14 * under the License. 15 */ 16 package io.netty.channel; 17 18 /** 19 * Responsible to estimate the size of a message. The size represents approximately how much memory the message will 20 * reserve in memory. 21 */ 22 public interface MessageSizeEstimator { 23 24 /** 25 * Creates a new handle. The handle provides the actual operations. 26 */ 27 Handle newHandle(); 28 29 interface Handle { 30 31 /** 32 * Calculate the size of the given message. 33 * 34 * @param msg The message for which the size should be calculated 35 * @return size The size in bytes. The returned size must be >= 0 36 */ 37 int size(Object msg); 38 } 39 }