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ASF GitHub Bot commented on FLINK-2017: --------------------------------------- Github user rmetzger commented on a diff in the pull request: https://github.com/apache/flink/pull/1097#discussion_r45172895 --- Diff: flink-java/src/main/java/org/apache/flink/api/java/utils/Option.java --- @@ -0,0 +1,195 @@ +/* + * 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.api.java.utils; + +import java.util.Arrays; +import java.util.Collections; +import java.util.HashSet; +import java.util.Objects; +import java.util.Set; + +/** + * Internal representation of a parameter passed to a user defined function. + */ +public class Option { + + private String longName; + private String shortName; + + private String defaultValue; + private Set<String> choices; + + private String helpText; + private OptionType type = OptionType.STRING; + + public Option(String name) { + this.longName = name; + this.choices = new HashSet<>(); + } + + /** + * Define a alternative / short name of the Parameter. + * + * @param shortName - short version of the parameter name + * @return the updated Option + */ + public Option alt(String shortName) { --- End diff -- Maybe we should add a comment here that only one alternative is allowed. or we add it as a feature to allow multiple alternatives ;) > Add predefined required parameters to ParameterTool > --------------------------------------------------- > > Key: FLINK-2017 > URL: https://issues.apache.org/jira/browse/FLINK-2017 > Project: Flink > Issue Type: Improvement > Affects Versions: 0.9 > Reporter: Robert Metzger > Labels: starter > > In FLINK-1525 we've added the {{ParameterTool}}. > During the PR review, there was a request for required parameters. > This issue is about implementing a facility to define required parameters. > The tool should also be able to print a help menu with a list of all > parameters. > This test case shows my initial ideas how to design the API > {code} > @Test > public void requiredParameters() { > RequiredParameters required = new RequiredParameters(); > Option input = required.add("input").alt("i").help("Path to > input file or directory"); // parameter with long and short variant > required.add("output"); // parameter only with long variant > Option parallelism = > required.add("parallelism").alt("p").type(Integer.class); // parameter with > type > Option spOption = > required.add("sourceParallelism").alt("sp").defaultValue(12).help("Number > specifying the number of parallel data source instances"); // parameter with > default value, specifying the type. > Option executionType = > required.add("executionType").alt("et").defaultValue("pipelined").choices("pipelined", > "batch"); > ParameterUtil parameter = ParameterUtil.fromArgs(new > String[]{"-i", "someinput", "--output", "someout", "-p", "15"}); > required.check(parameter); > required.printHelp(); > required.checkAndPopulate(parameter); > String inputString = input.get(); > int par = parallelism.getInteger(); > String output = parameter.get("output"); > int sourcePar = parameter.getInteger(spOption.getName()); > } > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)