Java tutorial
/** * 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.tajo.plan.serder; import com.google.gson.*; import org.apache.tajo.json.CommonGsonHelper; import org.apache.tajo.plan.logical.LogicalNode; import org.apache.tajo.plan.logical.NodeType; import org.apache.tajo.json.GsonSerDerAdapter; import java.lang.reflect.Type; public class LogicalNodeAdapter implements GsonSerDerAdapter<LogicalNode> { @Override public LogicalNode deserialize(JsonElement src, Type type, JsonDeserializationContext ctx) throws JsonParseException { JsonObject jsonObject = src.getAsJsonObject(); String nodeName = CommonGsonHelper.getOrDie(jsonObject, "type").getAsString(); Class clazz = NodeType.valueOf(nodeName).getBaseClass(); return ctx.deserialize(jsonObject.get("body"), clazz); } @Override public JsonElement serialize(LogicalNode src, Type typeOfSrc, JsonSerializationContext context) { JsonObject json = new JsonObject(); json.addProperty("type", src.getType().name()); json.add("body", context.serialize(src)); return json; } }