# Interface HasMultipleValues<T>

Type Parameters:
  `T` - the type of elements.

All Superinterfaces:
  `HasConfigurableValue, SupportsConvention`

All Known Subinterfaces:
  `ListProperty<T>, SetProperty<T>`

@SupportsKotlinAssignmentOverloading public interface HasMultipleValues<T> extends HasConfigurableValue, SupportsConvention
Represents a property whose value can be set using multiple elements of type `T`, such as a collection property.

Note: This interface is not intended for implementation by build script or plugin authors. You can use the factory methods on `ObjectFactory` to create various subtypes of this interface.

Since:
  4.5

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `add(Provider<? extends T> provider)`
  Adds an element to the property value.
  `void`
  `add(T element)`
  Adds an element to the property value.
  `void`
  `addAll(Iterable<? extends T> elements)`
  Adds zero or more elements to the property value.
  `void`
  `addAll(Provider<? extends Iterable<? extends T>> provider)`
  Adds zero or more elements to the property value.
  `void`
  `addAll(T... elements)`
  Adds zero or more elements to the property value.
  `HasMultipleValues<T>`
  `convention(@Nullable Iterable<? extends T> elements)`
  Specifies the value to use as the convention for this property.
  `HasMultipleValues<T>`
  `convention(Provider<? extends Iterable<? extends T>> provider)`
  Specifies the provider of the value to use as the convention for this property.
  `HasMultipleValues<T>`
  `empty()`
  Sets the value of this property to an empty collection, and replaces any existing value.
  `void`
  `finalizeValue()`
  Disallows further changes to the value of this property.
  `void`
  `set(@Nullable Iterable<? extends T> elements)`
  Sets the value of the property to the elements of the given iterable, and replaces any existing value.
  `void`
  `set(Provider<? extends Iterable<? extends T>> provider)`
  Sets the property to have the same value of the given provider, and replaces any existing value.
  `HasMultipleValues<T>`
  `value(@Nullable Iterable<? extends T> elements)`
  Sets the value of the property to the elements of the given iterable, and replaces any existing value.
  `HasMultipleValues<T>`
  `value(Provider<? extends Iterable<? extends T>> provider)`
  Sets the property to have the same value of the given provider, and replaces any existing value.

  ### Methods inherited from interface HasConfigurableValue

  `disallowChanges, disallowUnsafeRead, finalizeValueOnRead`

  ### Methods inherited from interface SupportsConvention

  `unset, unsetConvention`

- ## Method Details

  - ### set

    void set(@Nullable Iterable<? extends T> elements)
    Sets the value of the property to the elements of the given iterable, and replaces any existing value. This property will query the elements of the iterable each time the value of this property is queried.

    This method can also be used to discard the value of the property, by passing `null` as the value. The convention for this property, if any, will be used to provide the value instead.

    Parameters:
      `elements` - The elements, can be null.

  - ### set

    void set(Provider<? extends Iterable<? extends T>> provider)
    Sets the property to have the same value of the given provider, and replaces any existing value. This property will track the value of the provider and query its value each time the value of this property is queried. When the provider has no value, this property will also have no value.
    Parameters:
      `provider` - Provider of the elements.

  - ### value

    HasMultipleValues<T> value(@Nullable Iterable<? extends T> elements)
    Sets the value of the property to the elements of the given iterable, and replaces any existing value. This property will query the elements of the iterable each time the value of this property is queried.

    This is the same as `set(Iterable)` but returns this property to allow method chaining.

    Parameters:
      `elements` - The elements, can be null.
    Returns:
      this
    Since:
      5.6

  - ### value

    HasMultipleValues<T> value(Provider<? extends Iterable<? extends T>> provider)
    Sets the property to have the same value of the given provider, and replaces any existing value. This property will track the value of the provider and query its value each time the value of this property is queried. When the provider has no value, this property will also have no value.

    This is the same as `set(Provider)` but returns this property to allow method chaining.

    Parameters:
      `provider` - Provider of the elements.
    Returns:
      this
    Since:
      5.6

  - ### empty

    HasMultipleValues<T> empty()
    Sets the value of this property to an empty collection, and replaces any existing value.
    Returns:
      this property.
    Since:
      5.0

  - ### add

    void add(T element)
    Adds an element to the property value.
    Parameters:
      `element` - The element

  - ### add

    void add(Provider<? extends T> provider)
    Adds an element to the property value.

    The given provider will be queried when the value of this property is queried. This property will have no value when the given provider has no value.

    Parameters:
      `provider` - The provider of an element

  - ### addAll

    void addAll(T... elements)
    Adds zero or more elements to the property value.
    Parameters:
      `elements` - The elements to add
    Since:
      4.10

  - ### addAll

    void addAll(Iterable<? extends T> elements)
    Adds zero or more elements to the property value.

    The given iterable will be queried when the value of this property is queried.

    Parameters:
      `elements` - The elements to add.
    Since:
      4.10

  - ### addAll

    void addAll(Provider<? extends Iterable<? extends T>> provider)
    Adds zero or more elements to the property value.

    The given provider will be queried when the value of this property is queried. This property will have no value when the given provider has no value.

    Parameters:
      `provider` - Provider of elements

  - ### convention

    HasMultipleValues<T> convention(@Nullable Iterable<? extends T> elements)
    Specifies the value to use as the convention for this property. The convention is used when no value has been set for this property.
    Parameters:
      `elements` - The elements, or `null` when the convention is that the property has no value.
    Returns:
      this
    Since:
      5.1

  - ### convention

    HasMultipleValues<T> convention(Provider<? extends Iterable<? extends T>> provider)
    Specifies the provider of the value to use as the convention for this property. The convention is used when no value has been set for this property.
    Parameters:
      `provider` - The provider of the elements
    Returns:
      this
    Since:
      5.1

  - ### finalizeValue

    void finalizeValue()
    Disallows further changes to the value of this property. Calls to methods that change the value of this property, such as `set(Iterable)` or `add(Object)` will fail.

    When this property has elements provided by a `Provider`, the value of the provider is queried when this method is called and the value of the provider will no longer be tracked.

    Note that although the value of the property will not change, the resulting collection may contain mutable objects. Calling this method does not guarantee that the value will become immutable.

    Specified by:
      `finalizeValue` in interface `HasConfigurableValue`
    Since:
      5.0