1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 */ 18 19 package org.apache.giraph.utils; 20 21 import org.apache.hadoop.io.Writable; 22 import org.apache.hadoop.io.WritableComparable; 23 24 /** 25 * Special iterator that reuses vertex ids and message objects so that the 26 * lifetime of the object is only until next() is called. 27 * 28 * @param <I> vertexId type parameter 29 * @param <M> message type parameter 30 */ 31 public interface VertexIdMessageIterator<I extends WritableComparable, 32 M extends Writable> extends VertexIdDataIterator<I, M> { 33 /** 34 * Get the current message. 35 * 36 * @return Current message 37 */ 38 M getCurrentMessage(); 39 40 /** 41 * Get the serialized size of current message 42 * 43 * @return serialized size of current message 44 */ 45 int getCurrentMessageSize(); 46 47 /** 48 * Return true of current message is new 49 * 50 * @return true if current message is new 51 */ 52 boolean isNewMessage(); 53 }