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ASF GitHub Bot commented on FLINK-2017: --------------------------------------- Github user rmetzger commented on the pull request: https://github.com/apache/flink/pull/1097#issuecomment-157645907 Thank you for reviewing the pull request while I was away @fhueske. I've just tried it out with this code: ```java RequiredParameters rp = new RequiredParameters(); rp.add("input"); rp.add("output"); rp.add(new Option("parallelism").alt("p").help("Set the parallelism for all operators").type(OptionType.INTEGER)); ParameterTool pt = ParameterTool.fromArgs(args); try { rp.applyTo(pt); } catch(RequiredParametersException rpe) { System.out.println(rp.getHelp()); System.exit(1); } ``` and the output is the following: ``` Required Parameter name, short name, help text, default valueinput null output null parallelism p Set the parallelism for all operators ``` I think the `getHelp` method is not producing helpful output here. How about something like: ``` Required Parameters: --input --output -p, --parallelism Set the parallelism for all operators ``` The `RequiredParametersException` could list the missing arguments. > 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)