Package org.gradle.api

## Interface PolymorphicDomainObjectContainer<T>

- Type Parameters:
    `T` - the (base) type of objects in the container
  All Superinterfaces:
    `Collection<T>`, `Configurable<NamedDomainObjectContainer<T>>`, `DomainObjectCollection<T>`, `Iterable<T>`, `NamedDomainObjectCollection<T>`, `NamedDomainObjectContainer<T>`, `NamedDomainObjectSet<T>`, `Set<T>`
  All Known Subinterfaces:
    `AuthenticationContainer`, `ExtensiblePolymorphicDomainObjectContainer<T>`, `NativeToolChainRegistry`, `PlatformContainer`, `PublicationContainer`, `Repositories`, `TaskContainer`

      public interface PolymorphicDomainObjectContainer<T>
      extends NamedDomainObjectContainer<T>

  A `NamedDomainObjectContainer` that allows you to create objects with different types.

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `<U extends T> NamedDomainObjectContainer<U>` | `containerWithType​(Class<U> type)` | Creates a regular container that wraps the polymorphic container presenting all elements of a specified type.
    `<U extends T> U` | `create​(String name, Class<U> type)` | Creates a domain object with the specified name and type, and adds it to the container.
    `<U extends T> U` | `create​(String name, Class<U> type, Action<? super U> configuration)` | Creates a domain object with the specified name and type, adds it to the container, and configures it with the specified action.
    `<U extends T> U` | `maybeCreate​(String name, Class<U> type)` | Looks for an item with the given name and type, creating and adding it to this container if it does not exist.
    `<U extends T> NamedDomainObjectProvider<U>` | `register​(String name, Class<U> type)` | Defines a new object, which will be created when it is required.
    `<U extends T> NamedDomainObjectProvider<U>` | `register​(String name, Class<U> type, Action<? super U> configurationAction)` | Defines a new object, which will be created and configured when it is required.

    - ### Methods inherited from interface java.util.Collection

      `parallelStream, removeIf, stream, toArray`

    - ### Methods inherited from interface org.gradle.api.DomainObjectCollection

      `addAllLater, addLater, all, all, configureEach, whenObjectAdded, whenObjectAdded, whenObjectRemoved, whenObjectRemoved, withType, withType`

    - ### Methods inherited from interface java.lang.Iterable

      `forEach`

    - ### Methods inherited from interface org.gradle.api.NamedDomainObjectCollection

      `add, addAll, addRule, addRule, addRule, findByName, getAsMap, getAt, getByName, getByName, getByName, getCollectionSchema, getNamer, getNames, getRules, named, named, named, named`

    - ### Methods inherited from interface org.gradle.api.NamedDomainObjectContainer

      `configure, create, create, create, maybeCreate, register, register`

    - ### Methods inherited from interface org.gradle.api.NamedDomainObjectSet

      `findAll, matching, matching, withType`

    - ### Methods inherited from interface java.util.Set

      `add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, spliterator, toArray, toArray`

- - ### Method Detail

    - #### create

          <U extends T> U create​(String name,
                                 Class<U> type)
                          throws InvalidUserDataException

      Creates a domain object with the specified name and type, and adds it to the container.
      Type Parameters:
        `U` - the type of the domain object to be created
      Parameters:
        `name` - the name of the domain object to be created
        `type` - the type of the domain object to be created
      Returns:
        the created domain object
      Throws:
        `InvalidUserDataException` - if a domain object with the specified name already exists or the container does not support creating a domain object with the specified type

    - #### maybeCreate

          <U extends T> U maybeCreate​(String name,
                                      Class<U> type)
                               throws InvalidUserDataException

      Looks for an item with the given name and type, creating and adding it to this container if it does not exist.
      Type Parameters:
        `U` - the type of the domain object to be created
      Parameters:
        `name` - the name of the domain object to be created
        `type` - the type of the domain object to be created
      Returns:
        the found or created domain object, never `null`.
      Throws:
        `InvalidUserDataException` - if the container does not support creating a domain object with the specified type
        `ClassCastException` - if a domain object with the specified name exists with a different type

    - #### create

          <U extends T> U create​(String name,
                                 Class<U> type,
                                 Action<? super U> configuration)
                          throws InvalidUserDataException

      Creates a domain object with the specified name and type, adds it to the container, and configures it with the specified action.
      Type Parameters:
        `U` - the type of the domain object to be created
      Parameters:
        `name` - the name of the domain object to be created
        `type` - the type of the domain object to be created
        `configuration` - an action for configuring the domain object
      Returns:
        the created domain object
      Throws:
        `InvalidUserDataException` - if a domain object with the specified name already exists or the container does not support creating a domain object with the specified type

    - #### containerWithType

          <U extends T> NamedDomainObjectContainer<U> containerWithType​(Class<U> type)

      Creates a regular container that wraps the polymorphic container presenting all elements of a specified type.
      Type Parameters:
        `U` - the type of the container elements
      Parameters:
        `type` - the type of the container elements
      Returns:
        a `NamedDomainObjectContainer` providing access to elements of type U.

    - #### register

          <U extends T> NamedDomainObjectProvider<U> register​(String name,
                                                              Class<U> type,
                                                              Action<? super U> configurationAction)
                                                       throws InvalidUserDataException

      Defines a new object, which will be created and configured when it is required. A object is 'required' when the object is located using query methods such as `NamedDomainObjectCollection.getByName(String)` or when `Provider.get()` is called on the return value of this method.

      It is generally more efficient to use this method instead of `create(String, Class, Action)` or `create(String, Class)`, as those methods will eagerly create and configure the object, regardless of whether that object is required for the current build or not. This method, on the other hand, will defer creation and configuration until required.

      Type Parameters:
        `U` - The object type
      Parameters:
        `name` - The name of the object.
        `type` - The object type.
        `configurationAction` - The action to run to configure the object. This action runs when the object is required.
      Returns:
        A `Provider` that whose value will be the object, when queried.
      Throws:
        `InvalidUserDataException` - If a object with the given name already exists in this project.
      Since:
        4.10

    - #### register

          <U extends T> NamedDomainObjectProvider<U> register​(String name,
                                                              Class<U> type)
                                                       throws InvalidUserDataException

      Defines a new object, which will be created when it is required. A object is 'required' when the object is located using query methods such as `NamedDomainObjectCollection.getByName(String)` or when `Provider.get()` is called on the return value of this method.

      It is generally more efficient to use this method instead of `create(String, Class, Action)` or `create(String, Class)`, as those methods will eagerly create and configure the object, regardless of whether that object is required for the current build or not. This method, on the other hand, will defer creation until required.

      Type Parameters:
        `U` - The object type
      Parameters:
        `name` - The name of the object.
        `type` - The object type.
      Returns:
        A `Provider` that whose value will be the object, when queried.
      Throws:
        `InvalidUserDataException` - If a object with the given name already exists in this project.
      Since:
        4.10