DeltaStream

open class DeltaStream : DataValue, @unchecked Sendable

A stream of delta items, each of which is either an EntityValue or a ChangedLink. While processing a stream, a delta link may be encountered, but it will not be immediately available to the caller. The deltaLink can be obtained only after the stream is closed.

Example

let deltaStream = ...
while (deltaStream.next())
{
    if (deltaStream.hasEntity())
    {
        let entity = deltaStream.getEntity()
        // Process entity value.
    }
    else
    {
        let link = deltaStream.getLink()
        // Process changed link.
    }
}
deltaStream.close()
var deltaLink = deltaStream.deltaLink
// Save delta link for later use.

  • Has close been called?

    Declaration

    Swift

    final public var isClosed: Bool

  • The current delta item (an EntityValue or ChangedLink), or nil.

    Declaration

    Swift

    final public var deltaItem: AnyObject?

  • The delta-link (if any) that was encountered when next was called repeatedly until it returned false and then close was called, otherwise nil.

    Declaration

    Swift

    final public var deltaLink: String?

  • The next-link (if any) that was encountered when next was called repeatedly until it returned false and then close was called, otherwise nil.

    Declaration

    Swift

    final public var nextLink: String?

  • The read-link (if any) that was encountered when next was called repeatedly until it returned false and then close was called, otherwise nil.

    Declaration

    Swift

    final public var readLink: String?

  • Default initializer.

    Declaration

    Swift

    override public init()

  • Close this stream and release all associated resources, without checking first that the end of stream has been reached.

    See also

    close.

    Declaration

    Swift

    open func abort() throws

  • Close this stream and release all associated resources, checking first that the end of stream has been reached. Can safely be called even if the stream was previously closed. If a delta link was encountered before the stream was closed, it will be available via the deltaLink property only after the stream is closed. If a next link was encountered before the stream was closed, it will be available via the nextLink property only after the stream is closed.

    See also

    abort.

    Declaration

    Swift

    open func close() throws

  • See also

    hasCurrent.

    Declaration

    Swift

    open func current() throws -> AnyObject?

    Return Value

    the current delta item (an EntityValue or ChangedLink), or nil if there is no current delta item.

  • Data type with a DataType.code of DataType.DELTA_STREAM.

    Declaration

    Swift

    override open var dataType: DataType { get }

  • Throws

    UsageException if there no current delta item or if the current delta item is a changed link.

    See also

    getCurrent.

    Declaration

    Swift

    open func entity() throws -> EntityValue

    Return Value

    the current entity value.

  • See also

    getCurrent.

    Declaration

    Swift

    open func hasCurrent() throws -> Bool

    Return Value

    true if the if the stream has a current delta item (the most recent call to next returned true and close has not been called)).

  • Check if the stream has a current delta item which is an entity value.

    See also

    getEntity.

    Declaration

    Swift

    open func hasEntity() throws -> Bool

    Return Value

    true if hasCurrent would return true if called, and the current delta item is an entity value.

  • Check if the stream has a current delta item which is a changed link.

    See also

    getLink.

    Declaration

    Swift

    open func hasLink() throws -> Bool

    Return Value

    true if hasCurrent would return true if called, and the current delta item is a changed link.

  • Throws

    UsageException if there is no current delta item or if the current delta item is an entity value.

    See also

    getCurrent.

    Declaration

    Swift

    open func link() throws -> ChangedLink

    Return Value

    the current changed link.

  • If this stream has not been close and has a next delta item, then advance to the next delta item and return true. Otherwise return false.

    See also

    hasCurrent, hasEntity, hasLink, getCurrent, getEntity, getLink.

    Declaration

    Swift

    open func next() throws -> Bool

    Return Value

    true if there is a next delta item available.

  • Convert this data value to a string. If the dataType is defined by XML Schema Part 2: Datatypes, then the corresponding lexical format is used. JSON format is used for structured values (arrays and objects).

    Declaration

    Swift

    override open func toString() -> String

    Return Value

    Lexical representation of this data value.