Struct UpdateIterator 

pub struct UpdateIterator<DC>
where
    DC: DataController + Send + Sync + 'static,
{ /* private fields */ }

Iterator over updates in the cache.

This is a crucial part of the write-back mechanism. Despite its name reflecting the primary function of the struct, it does not implement the Iterator trait but provides a next() method to iterate over updates. This is because it incorporates aspects of a collection’s behavior, making it more than just a simple iterator.

Note that an important part of implementing a write back method is to remember to confirm the successfully processed updates. Unconfirmed ones will be put back into the update pool for later processing. Confirmation can be done by calling the confirm_all() method or by calling confirm() on each item returned by the next() method. The former approach is useful for transactional updates.

Implementations

impl<DC> UpdateIterator<DC>

where DC: DataController + Send + Sync + 'static,

pub fn confirm_all(&self)

Confirm all updates at once. Useful for transactional updates.

pub fn len(&self) -> usize

The number of update records to process.

pub fn is_empty(&self) -> bool

pub fn next(&self) -> Option<UpdateIteratorItem<DC>>

Get the next update item to process or None if there are no more items left.

It is possible that not all of the updates, bundled with the current iterator, will be returned by this method. This can happen due to the concurrent nature of the cache and the fact that updates can be flushed by other threads.

pub fn reset(&self)

Reset the iterator to the initial state to allow re-iterating over the same updates. Mostly useful for cache controller’s own purposes.

Trait Implementations

impl<DC> Child for UpdateIterator<DC>

where DC: DataController + Send + Sync + 'static,

type WeakParent = Weak<Cache<DC>>

Type of weak reference to the parent.

type FXPParent = Arc<Cache<DC>>

For use of the child_build! and child_builder! macros.

type RcParent = Arc<Cache<DC>>

Type of strong reference to the parent.

fn parent(&self) -> Self::RcParent

Return a strong reference to the parent.

fn parent_downgrade(&self) -> Self::WeakParent

Return a weak reference to the parent.

fn __fxplus_parent(parent: Self::WeakParent) -> Self::FXPParent

impl<DC> Parent for UpdateIterator<DC>

where DC: DataController + Send + Sync + 'static,

type WeakSelf = Weak<UpdateIterator<DC>>

Weak ref-count type for the parent to hold a reference to itself.

fn __fxplus_myself_downgrade(&self) -> Weak<Self>

impl<DC> FXStruct for UpdateIterator<DC>

where DC: DataController + Send + Sync + 'static,