| /** |
| * 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.apex.malhar.lib.appdata; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.google.common.base.Preconditions; |
| |
| import com.datatorrent.api.Context; |
| import com.datatorrent.api.DefaultInputPort; |
| import com.datatorrent.api.Operator; |
| import com.datatorrent.api.annotation.InputPortFieldAnnotation; |
| import com.datatorrent.common.experimental.AppData; |
| |
| /** |
| * This is an operator that lays the framework of serving data to queries coming from an embeddable query info provider, |
| * which may be an input operator. |
| * Subclasses are expected to implement the processQuery method for the logic of handling the query. Note that |
| * processQuery cannot directly emit to the operator's output port because it's called from the thread of the |
| * embeddable query info provider. |
| * |
| * @since 3.8.0 |
| */ |
| public abstract class AbstractAppDataServer<QueryType> implements Operator, AppData.Store<QueryType> |
| { |
| @AppData.QueryPort |
| @InputPortFieldAnnotation(optional = true) |
| public final transient DefaultInputPort<QueryType> query = new DefaultInputPort<QueryType>() |
| { |
| @Override |
| public void process(QueryType query) |
| { |
| processQuery(query); |
| } |
| }; |
| |
| |
| protected AppData.EmbeddableQueryInfoProvider<QueryType> embeddableQueryInfoProvider; |
| |
| |
| protected abstract void processQuery(QueryType query); |
| |
| @Override |
| public void activate(Context.OperatorContext ctx) |
| { |
| if (embeddableQueryInfoProvider != null) { |
| embeddableQueryInfoProvider.activate(ctx); |
| } |
| } |
| |
| @SuppressWarnings("unchecked") |
| @Override |
| public void setup(Context.OperatorContext context) |
| { |
| if (embeddableQueryInfoProvider != null) { |
| embeddableQueryInfoProvider.enableEmbeddedMode(); |
| LOG.info("An embeddable query operator is being used of class {}.", embeddableQueryInfoProvider.getClass().getName()); |
| StoreUtils.attachOutputPortToInputPort(embeddableQueryInfoProvider.getOutputPort(), query); |
| embeddableQueryInfoProvider.setup(context); |
| } |
| } |
| |
| @Override |
| public void beginWindow(long windowId) |
| { |
| if (embeddableQueryInfoProvider != null) { |
| embeddableQueryInfoProvider.beginWindow(windowId); |
| } |
| } |
| |
| @Override |
| public void endWindow() |
| { |
| if (embeddableQueryInfoProvider != null) { |
| embeddableQueryInfoProvider.endWindow(); |
| } |
| } |
| |
| @Override |
| public void teardown() |
| { |
| if (embeddableQueryInfoProvider != null) { |
| embeddableQueryInfoProvider.teardown(); |
| } |
| } |
| |
| @Override |
| public void deactivate() |
| { |
| if (embeddableQueryInfoProvider != null) { |
| embeddableQueryInfoProvider.deactivate(); |
| } |
| } |
| |
| @Override |
| public AppData.EmbeddableQueryInfoProvider<QueryType> getEmbeddableQueryInfoProvider() |
| { |
| return embeddableQueryInfoProvider; |
| } |
| |
| @Override |
| public void setEmbeddableQueryInfoProvider(AppData.EmbeddableQueryInfoProvider<QueryType> embeddableQueryInfoProvider) |
| { |
| this.embeddableQueryInfoProvider = Preconditions.checkNotNull(embeddableQueryInfoProvider); |
| } |
| |
| private static final Logger LOG = LoggerFactory.getLogger(AbstractAppDataServer.class); |
| |
| } |