org.apache.flink.api.java.utils

类 RequiredParameters

java.lang.Object

org.apache.flink.api.java.utils.RequiredParameters

@PublicEvolving
public class RequiredParameters
extends Object

Facility to manage required parameters in user defined functions.

构造器概要

构造器

构造器和说明
RequiredParameters()

方法概要

限定符和类型	方法和说明
void	add(Option option) Add a parameter encapsulated in an Option object.
Option	add(String name) Add a parameter based on its name.
ParameterTool	applyTo(ParameterTool parameterTool) Check for all required parameters defined: - has a value been passed - if not, does the parameter have an associated default value - does the type of the parameter match the one defined in RequiredParameters - does the value provided in the parameterTool adhere to the choices defined in the option.
String	getHelp() Build a help text for the defined parameters.
String	getHelp(List<String> missingArguments) Build a help text for the defined parameters and list the missing arguments at the end of the text.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

RequiredParameters

public RequiredParameters()

方法详细资料

add

public Option add(String name)
           throws RequiredParametersException

Add a parameter based on its name.

参数:

name - - the name of the parameter

返回:

- an Option object representing the parameter

抛出:

RequiredParametersException - if an option with the same name is already defined

add

public void add(Option option)
         throws RequiredParametersException

Add a parameter encapsulated in an Option object.

参数:

option - - the parameter

抛出:

RequiredParametersException - if an option with the same name is already defined

applyTo

public ParameterTool applyTo(ParameterTool parameterTool)
                      throws RequiredParametersException

Check for all required parameters defined: - has a value been passed - if not, does the parameter have an associated default value - does the type of the parameter match the one defined in RequiredParameters - does the value provided in the parameterTool adhere to the choices defined in the option.

If any check fails, a RequiredParametersException is thrown

参数:

parameterTool - - parameters supplied by the user.

返回:

the updated ParameterTool containing all the required parameters

抛出:

RequiredParametersException - if any of the specified checks fail

getHelp

public String getHelp()

Build a help text for the defined parameters.

The format of the help text will be: Required Parameters: \t -:shortName:, --:name: \t :helpText: \t default: :defaultValue: \t choices: :choices: \n

返回:

a formatted help String.

getHelp

public String getHelp(List<String> missingArguments)

Build a help text for the defined parameters and list the missing arguments at the end of the text.

The format of the help text will be: Required Parameters: \t -:shortName:, --:name: \t :helpText: \t default: :defaultValue: \t choices: :choices: \n

Missing parameters: \t param1 param2 ... paramN

参数:

missingArguments - - a list of missing parameters

返回:

a formatted help String.