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.twill.internal.json; import com.google.common.reflect.TypeToken; import com.google.gson.JsonDeserializationContext; import com.google.gson.JsonDeserializer; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import com.google.gson.JsonParseException; import com.google.gson.JsonSerializationContext; import com.google.gson.JsonSerializer; import org.apache.twill.api.LocalFile; import org.apache.twill.api.ResourceSpecification; import org.apache.twill.api.RuntimeSpecification; import org.apache.twill.api.TwillRunnableSpecification; import org.apache.twill.internal.DefaultRuntimeSpecification; import java.lang.reflect.Type; import java.util.Collection; /** * Gson codec for {@link RuntimeSpecification}. */ final class RuntimeSpecificationCodec implements JsonSerializer<RuntimeSpecification>, JsonDeserializer<RuntimeSpecification> { @Override public JsonElement serialize(RuntimeSpecification src, Type typeOfSrc, JsonSerializationContext context) { JsonObject json = new JsonObject(); json.addProperty("name", src.getName()); json.add("runnable", context.serialize(src.getRunnableSpecification(), TwillRunnableSpecification.class)); json.add("resources", context.serialize(src.getResourceSpecification(), ResourceSpecification.class)); json.add("files", context.serialize(src.getLocalFiles(), new TypeToken<Collection<LocalFile>>() { }.getType())); return json; } @Override public RuntimeSpecification deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException { JsonObject jsonObj = json.getAsJsonObject(); String name = jsonObj.get("name").getAsString(); TwillRunnableSpecification runnable = context.deserialize(jsonObj.get("runnable"), TwillRunnableSpecification.class); ResourceSpecification resources = context.deserialize(jsonObj.get("resources"), ResourceSpecification.class); Collection<LocalFile> files = context.deserialize(jsonObj.get("files"), new TypeToken<Collection<LocalFile>>() { }.getType()); return new DefaultRuntimeSpecification(name, runnable, resources, files); } }