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, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 * 19 */ 20 package org.apache.directory.mavibot.btree.serializer; 21 22 23 import java.io.IOException; 24 import java.nio.ByteBuffer; 25 import java.util.Comparator; 26 27 28 /** 29 * This interface is used by implementations of serializer, deserializer and comparator. 30 * 31 * @param <T> The type for the element to serialize and compare 32 * 33 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 34 */ 35 public interface ElementSerializer<T> 36 { 37 /** 38 * Produce the byte[] representation of the element 39 * 40 * @param key The element to serialize 41 * @return The byte[] containing the serialized element 42 */ 43 byte[] serialize( T key ); 44 45 46 /** 47 * Deserialize an element from a BufferHandler 48 * 49 * @param bufferHandler The incoming bufferHandler 50 * @return The deserialized element 51 * @throws IOException If the deserialization failed 52 */ 53 T deserialize( BufferHandler bufferHandler ) throws IOException; 54 55 56 /** 57 * Deserialize an element from a ByteBuffer 58 * 59 * @param buffer The incoming ByteBuffer 60 * @return The deserialized element 61 * @throws IOException If the deserialization failed 62 */ 63 T deserialize( ByteBuffer buffer ) throws IOException; 64 65 66 /** 67 * Deserialize an element from a byte[] 68 * 69 * @param buffer The incoming byte[] 70 * @return The deserialized element 71 * @throws IOException If the deserialization failed 72 */ 73 T fromBytes( byte[] buffer ) throws IOException; 74 75 76 /** 77 * Deserialize an element from a byte[] 78 * 79 * @param buffer The incoming byte[] 80 * @return The deserialized element 81 * @throws IOException If the deserialization failed 82 */ 83 T fromBytes( byte[] buffer, int pos ) throws IOException; 84 85 86 /** 87 * Returns the comparison of two types. <br/> 88 * <ul> 89 * <li>If type1 < type2, return -1</li> 90 * <li>If type1 > type2, return 1</li> 91 * <li>If type1 == type2, return 0</li> 92 * </ul> 93 * 94 * @param type1 The first type to compare 95 * @param type2 The second type to compare 96 * @return The comparison result 97 */ 98 int compare( T type1, T type2 ); 99 100 101 /** 102 * @return the comparator for the used type 103 */ 104 Comparator<T> getComparator(); 105 106 107 /** 108 * @return the type being serialized 109 */ 110 Class<?> getType(); 111 }