becketqin commented on a change in pull request #9184: [FLINK-13339][ml] Add an implementation of pipeline's api URL: https://github.com/apache/flink/pull/9184#discussion_r333556130
########## File path: flink-ml-parent/flink-ml-lib/src/main/java/org/apache/flink/ml/common/MLEnvironmentFactory.java ########## @@ -0,0 +1,125 @@ +/* + * 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.flink.ml.common; + +import java.util.HashMap; + +/** + * Factory to get the MLEnvironment using a MLEnvironmentId. + * + * <p>The following code snippet shows how to interact with MLEnvironmentFactory. + * <pre> + * {@code + * long mlEnvId = MLEnvironmentFactory.getNewMLEnvironmentId(); + * MLEnvironment mlEnv = MLEnvironmentFactory.get(mlEnvId); + * } + * </pre> + */ +public class MLEnvironmentFactory { + + /** + * The default MLEnvironmentId. + */ + public static final Long DEFAULT_ML_ENVIRONMENT_ID = 0L; + + /** + * A 'id' is a unique identifier of a MLEnvironment. + */ + private static Long id = 1L; + + /** + * Map that hold the MLEnvironment and use the MLEnvironmentId as its key. + */ + private static final HashMap<Long, MLEnvironment> map = new HashMap<>(); + + /** + * Get the MLEnvironment using a MLEnvironmentId. + * The default MLEnvironment will be set a new MLEnvironment + * when there is no default MLEnvironment. + * + * @param mlEnvId the MLEnvironmentId + * @return the MLEnvironment + */ + public static synchronized MLEnvironment get(Long mlEnvId) { + if (!map.containsKey(mlEnvId)) { + if (mlEnvId.equals(DEFAULT_ML_ENVIRONMENT_ID)) { + setDefault(new MLEnvironment()); + } else { + throw new IllegalArgumentException("There is no Environment in factory. " + Review comment: Can we create the default ML Session in the static block? This will help simplify the logic here. Should we also include the EnvId in the error message? Something like: `String.format("Cannot find MLEnvironment for MLEnvironmentId %s. Did you get the MLEnvironmentId by calling `getNewMLEnvironmentId?", mlEnvId)` ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
