/** * 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 kafka.serializer import kafka.utils.VerifiableProperties /** * An encoder is a method of turning objects into byte arrays. * An implementation is required to provide a constructor that * takes a VerifiableProperties instance. */ trait Encoder[T] { def toBytes(t: T): Array[Byte] } /** * The default implementation is a no-op, it just returns the same array it takes in */ class DefaultEncoder(props: VerifiableProperties = null) extends Encoder[Array[Byte]] { override def toBytes(value: Array[Byte]): Array[Byte] = value } class NullEncoder[T](props: VerifiableProperties = null) extends Encoder[T] { override def toBytes(value: T): Array[Byte] = null } /** * The string encoder takes an optional parameter serializer.encoding which controls * the character set used in encoding the string into bytes. */ class StringEncoder(props: VerifiableProperties = null) extends Encoder[String] { val encoding = if(props == null) "UTF8" else props.getString("serializer.encoding", "UTF8") override def toBytes(s: String): Array[Byte] = if(s == null) null else s.getBytes(encoding) }