# Annotation Type Option

@Retention(RUNTIME) @Target({METHOD,FIELD}) @Inherited public @interface Option

Marks a property of a `Task` as being configurable from the command-line.

This annotation should be attached to a field or a setter method. When attached to a field, `option()` will use the name of the field by default. When attached to a method, `option()` must be specified.

An option may have one of the following types:

- `boolean`, `Boolean`, or `Property<Boolean>`
- `Double` or `Property<Double>`
- `Integer` or `Property<Integer>`
- `Long` or `Property<Long>`
- `String` or `Property<String>`
- an `enum` type or `Property<T>` of an enum type
- `List<T>` of type `Double`, `Integer`, `Long`, `String`, or an `enum` type
- `ListProperty<T>` and `SetProperty<T>` of same type as `List<T>`
- `DirectoryProperty` or `RegularFileProperty`

Note: Multiple `@Option`s with the same names are disallowed on different methods/fields. Methods with the same signature (i.e. the same name, return type, and parameter types) are allowed to use equal or unequal option names.

When the option names are equal, the description and method linked to the option will be the one in the base class (if present), followed by super-classes, and finally interfaces, in an unspecified order.

When the option names are unequal, the order described above is used when setting the option's value. If the base class has an option with the name "foo" and an interface has an option with the name "bar", the option "foo" will have precedence over the option "bar" and setting both will result in the value of "foo".

Depending on this behavior is discouraged. It is only in place to allow legacy migration to interface options.

Since:
  4.6

- ## Required Element Summary

  Required Elements
  Modifier and Type
  Required Element
  Description
  `String`
  `description`
  The description of this option.

- ## Optional Element Summary

  Optional Elements
  Modifier and Type
  Optional Element
  Description
  `String`
  `option`
  The option to map to this property.

- ## Element Details

  - ### option

    String option
    The option to map to this property. Required when annotating a method. May be omitted when annotating a field in which case the field's name will be used.
    Returns:
      The option.
    Default:
      `""`

  - ### description

    String description
    The description of this option.
    Returns:
      The description.