| /** |
| * 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) |
| } |