Package org.springframework.core.env

Class SimpleCommandLinePropertySource

java.lang.Object
org.springframework.core.env.PropertySource<T>
org.springframework.core.env.EnumerablePropertySource<T>
org.springframework.core.env.CommandLinePropertySource<org.springframework.core.env.CommandLineArgs>
org.springframework.core.env.SimpleCommandLinePropertySource
public class SimpleCommandLinePropertySource extends CommandLinePropertySource<org.springframework.core.env.CommandLineArgs>
CommandLinePropertySource implementation backed by a simple String array.

Purpose

This CommandLinePropertySource implementation aims to provide the simplest possible approach to parsing command line arguments. As with all CommandLinePropertySource implementations, command line arguments are broken into two distinct groups: option arguments and non-option arguments, as described below (some sections copied from Javadoc for SimpleCommandLineArgsParser):

Working with option arguments

Option arguments must adhere to the exact syntax: 

--optName[=optValue]

That is, options must be prefixed with "--" and may or may not specify a value. If a value is specified, the name and value must be separated without spaces by an equals sign ("="). The value may optionally be an empty string.

Valid examples of option arguments

 --foo
 --foo=
 --foo=""
 --foo=bar
 --foo="bar then baz"
 --foo=bar,baz,biz

Invalid examples of option arguments

 -foo
 --foo bar
 --foo = bar
 --foo=bar --foo=baz --foo=biz

End of option arguments

The underlying parser supports the POSIX "end of options" delimiter, meaning that any "--" (empty option name) in the command line signals that all remaining arguments are non-option arguments. For example, "--opt1=ignored", "--opt2", and "filename" in the following command line are considered non-option arguments. 

 --foo=bar -- --opt1=ignored -opt2 filename

Working with non-option arguments

Any arguments following the "end of options" delimiter (--) or specified without the "--" option prefix will be considered as "non-option arguments" and made available through the CommandLineArgs.getNonOptionArgs() method.

Typical usage

 public static void main(String[] args) {
     PropertySource<?> ps = new SimpleCommandLinePropertySource(args);
     // ...
 }
See CommandLinePropertySource for complete general usage examples.

Beyond the basics

When more fully-featured command line parsing is necessary, consider implementing your own CommandLinePropertySource against the command line parsing library of your choice.

Since:
3.1
Author:
Chris Beams
See Also:

  • Constructor Details

    • SimpleCommandLinePropertySource

      public SimpleCommandLinePropertySource(String... args)
      Create a new SimpleCommandLinePropertySource having the default name and backed by the given String[] of command line arguments.
      See Also:

    • SimpleCommandLinePropertySource

      public SimpleCommandLinePropertySource(String name, String[] args)
      Create a new SimpleCommandLinePropertySource having the given name and backed by the given String[] of command line arguments.

  • Method Details

    • getPropertyNames

      public String[] getPropertyNames()
      Get the property names for the option arguments.
      Specified by:
      getPropertyNames in class EnumerablePropertySource<org.springframework.core.env.CommandLineArgs>

    • containsOption

      protected boolean containsOption(String name)
      Description copied from class: CommandLinePropertySource
      Return whether the set of option arguments parsed from the command line contains an option with the given name.
      Specified by:
      containsOption in class CommandLinePropertySource<org.springframework.core.env.CommandLineArgs>

    • getOptionValues

      @Nullable protected List<String> getOptionValues(String name)
      Description copied from class: CommandLinePropertySource
      Return the collection of values associated with the command line option having the given name.
      • if the option is present and has no argument (for example: "--foo"), return an empty collection ([])
      • if the option is present and has a single value (for example, "--foo=bar"), return a collection having one element (["bar"])
      • if the option is present and the underlying command line parsing library supports multiple arguments (for example, "--foo=bar --foo=baz"), return a collection having elements for each value (["bar", "baz"])
      • if the option is not present, return null
      Specified by:
      getOptionValues in class CommandLinePropertySource<org.springframework.core.env.CommandLineArgs>

    • getNonOptionArgs

      protected List<String> getNonOptionArgs()
      Description copied from class: CommandLinePropertySource
      Return the collection of non-option arguments parsed from the command line. Never null.
      Specified by:
      getNonOptionArgs in class CommandLinePropertySource<org.springframework.core.env.CommandLineArgs>