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.rya.kafka.connect.mongo; import static java.util.Objects.requireNonNull; import java.util.Arrays; import java.util.Map; import java.util.Optional; import org.apache.accumulo.core.client.AccumuloException; import org.apache.accumulo.core.client.AccumuloSecurityException; import org.apache.kafka.connect.errors.ConnectException; import org.apache.rya.api.client.RyaClient; import org.apache.rya.api.client.RyaClientException; import org.apache.rya.api.client.mongo.MongoConnectionDetails; import org.apache.rya.api.client.mongo.MongoRyaClientFactory; import org.apache.rya.api.log.LogUtils; import org.apache.rya.api.persist.RyaDAOException; import org.apache.rya.indexing.accumulo.ConfigUtils; import org.apache.rya.kafka.connect.api.sink.RyaSinkTask; import org.apache.rya.mongodb.MongoDBRdfConfiguration; import org.apache.rya.rdftriplestore.inference.InferenceEngineException; import org.apache.rya.sail.config.RyaSailFactory; import org.eclipse.rdf4j.sail.Sail; import org.eclipse.rdf4j.sail.SailException; import com.google.common.base.Strings; import com.mongodb.MongoClient; import com.mongodb.MongoCredential; import com.mongodb.ServerAddress; import edu.umd.cs.findbugs.annotations.DefaultAnnotation; import edu.umd.cs.findbugs.annotations.NonNull; import edu.umd.cs.findbugs.annotations.Nullable; /** * A {@link RyaSinkTask} that uses the Mongo DB implementation of Rya to store data. */ @DefaultAnnotation(NonNull.class) public class MongoRyaSinkTask extends RyaSinkTask { @Override protected void checkRyaInstanceExists(final Map<String, String> taskConfig) throws IllegalStateException { requireNonNull(taskConfig); // Parse the configuration object. final MongoRyaSinkConfig config = new MongoRyaSinkConfig(taskConfig); @Nullable final String username = Strings.isNullOrEmpty(config.getUsername()) ? null : config.getUsername(); @Nullable final char[] password = Strings.isNullOrEmpty(config.getPassword()) ? null : config.getPassword().toCharArray(); // Connect a Mongo Client to the configured Mongo DB instance. final ServerAddress serverAddr = new ServerAddress(config.getHostname(), config.getPort()); final boolean hasCredentials = username != null && password != null; try (MongoClient mongoClient = hasCredentials ? new MongoClient(serverAddr, Arrays.asList( MongoCredential.createCredential(username, config.getRyaInstanceName(), password))) : new MongoClient(serverAddr)) { // Use a RyaClient to see if the configured instance exists. // Create the Mongo Connection Details that describe the Mongo DB Server we are interacting with. final MongoConnectionDetails connectionDetails = new MongoConnectionDetails(config.getHostname(), config.getPort(), Optional.ofNullable(username), Optional.ofNullable(password)); final RyaClient client = MongoRyaClientFactory.build(connectionDetails, mongoClient); if (!client.getInstanceExists().exists(config.getRyaInstanceName())) { throw new ConnectException("The Rya Instance named " + LogUtils.clean(config.getRyaInstanceName()) + " has not been installed."); } } catch (final RyaClientException e) { throw new ConnectException("Unable to determine if the Rya Instance named " + LogUtils.clean(config.getRyaInstanceName()) + " has been installed.", e); } } @Override protected Sail makeSail(final Map<String, String> taskConfig) { requireNonNull(taskConfig); // Parse the configuration object. final MongoRyaSinkConfig config = new MongoRyaSinkConfig(taskConfig); // Move the configuration into a Rya Configuration object. final MongoDBRdfConfiguration ryaConfig = new MongoDBRdfConfiguration(); ConfigUtils.setUseMongo(ryaConfig, true); ryaConfig.setMongoDBName(config.getRyaInstanceName()); ryaConfig.setTablePrefix(config.getRyaInstanceName()); ryaConfig.setMongoHostname(config.getHostname()); ryaConfig.setMongoPort("" + config.getPort()); if (!Strings.isNullOrEmpty(config.getUsername()) && !Strings.isNullOrEmpty(config.getPassword())) { ryaConfig.setMongoUser(config.getUsername()); ryaConfig.setMongoPassword(config.getPassword()); } // Create the Sail object. try { return RyaSailFactory.getInstance(ryaConfig); } catch (SailException | AccumuloException | AccumuloSecurityException | RyaDAOException | InferenceEngineException e) { throw new ConnectException("Could not connect to the Rya Instance named " + config.getRyaInstanceName(), e); } } }