Class EnvironmentVariableDefaultProvider

  • All Implemented Interfaces:
    IDefaultProvider

    public final class EnvironmentVariableDefaultProvider
    extends Object
    implements IDefaultProvider
    A default provider that reads its default values from an environment variable. A prefix pattern can be provided to indicate how options are identified. The default pattern -/ mandates that options MUST start with either a dash or a slash. Options can have values separated by whitespace. Values can contain whitespace as long as they are single-quoted or double-quoted. Otherwhise whitespace identifies the end of a value.
    Author:
    Markus KARG (markus@headcrashing.eu)
    • Constructor Detail

      • EnvironmentVariableDefaultProvider

        public EnvironmentVariableDefaultProvider()
        Creates a default provider reading the environment variable JCOMMANDER_OPTS using the prefixes pattern -/.
      • EnvironmentVariableDefaultProvider

        public EnvironmentVariableDefaultProvider​(String environmentVariableName,
                                                  String optionPrefixes)
        Creates a default provider reading the specified environment variable using the specified prefixes pattern.
        Parameters:
        environmentVariableName - The name of the environment variable to read (e. g. "JCOMMANDER_OPTS"). Must not be null.
        optionPrefixes - A set of characters used to indicate the start of an option (e. g. "-/" if option names may start with either dash or slash). Must not be null.
    • Method Detail

      • getDefaultValueFor

        public final String getDefaultValueFor​(String optionName)
        Specified by:
        getDefaultValueFor in interface IDefaultProvider
        Parameters:
        optionName - The name of the option as specified in the names() attribute of the @Parameter option (e.g. "-file").
        Returns:
        the default value for this option.