| /* |
| * 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 org.apache.samza.serializers; |
| |
| import org.apache.samza.SamzaException; |
| import org.codehaus.jackson.map.ObjectMapper; |
| import org.codehaus.jackson.type.TypeReference; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.io.IOException; |
| import java.io.ObjectInputStream; |
| import java.io.UnsupportedEncodingException; |
| |
| /** |
| * A serializer for UTF-8 encoded JSON strings. JsonSerdeV2 differs from JsonSerde in that: |
| * <ol> |
| * <li> |
| * It allows specifying the specific POJO type to deserialize to (using JsonSerdeV2(Class<T>) |
| * or JsonSerdeV2#of(Class<T>). JsonSerde always returns a LinkedHashMap<String, Object> |
| * upon deserialization. |
| * <li> |
| * It uses Jackson's default 'camelCase' property naming convention, which simplifies defining |
| * the POJO to bind to. JsonSerde enforces the 'dash-separated' property naming convention. |
| * </ol> |
| * This JsonSerdeV2 should be preferred over JsonSerde for High Level API applications, unless |
| * backwards compatibility with the older data format (with dasherized names) is required. |
| * |
| * @param <T> the type of the POJO being (de)serialized. |
| */ |
| public class JsonSerdeV2<T> implements Serde<T> { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(JsonSerdeV2.class); |
| private final Class<T> clazz; |
| private transient ObjectMapper mapper = new ObjectMapper(); |
| |
| /** |
| * Constructs a JsonSerdeV2 that returns a LinkedHashMap<String, Object< upon deserialization. |
| */ |
| public JsonSerdeV2() { |
| this(null); |
| } |
| |
| /** |
| * Constructs a JsonSerdeV2 that (de)serializes POJOs of class {@code clazz}. |
| * |
| * @param clazz the class of the POJO being (de)serialized. |
| */ |
| public JsonSerdeV2(Class<T> clazz) { |
| this.clazz = clazz; |
| } |
| |
| public static <T> JsonSerdeV2<T> of(Class<T> clazz) { |
| return new JsonSerdeV2<>(clazz); |
| } |
| |
| public byte[] toBytes(T obj) { |
| if (obj != null) { |
| try { |
| String str = mapper.writeValueAsString(obj); |
| return str.getBytes("UTF-8"); |
| } catch (Exception e) { |
| throw new SamzaException("Error serializing data.", e); |
| } |
| } else { |
| return null; |
| } |
| } |
| |
| public T fromBytes(byte[] bytes) { |
| if (bytes != null) { |
| String str; |
| try { |
| str = new String(bytes, "UTF-8"); |
| } catch (UnsupportedEncodingException e) { |
| throw new SamzaException("Error deserializing data", e); |
| } |
| |
| try { |
| if (clazz != null) { |
| return mapper.readValue(str, clazz); |
| } else { |
| return mapper.readValue(str, new TypeReference<T>() { }); |
| } |
| } catch (Exception e) { |
| LOG.debug("Error deserializing data: " + str, e); |
| throw new SamzaException("Error deserializing data", e); |
| } |
| } else { |
| return null; |
| } |
| } |
| |
| private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { |
| in.defaultReadObject(); |
| this.mapper = new ObjectMapper(); |
| } |
| } |