net.openhft.chronicle.engine.api.tree

Interface Asset

All Superinterfaces:

AutoCloseable, Closeable

All Known Subinterfaces:

SubAsset<T>

All Known Implementing Classes:

VanillaAsset, VanillaSubAsset

public interface Asset
extends net.openhft.chronicle.core.io.Closeable

An Asset is a point on an AssetTree. An Asset can not only have any number of Children it has multiple views depending on how you want to access the data.

A single asset can have a MapView, EntrySetView, KeySetView, ValuesCollection, Subscription, TopicPublisher. A Map may be viewed in terms of the objects it holds e.g. String or Marshallable or the raw data i.e. as a BytesStore.

Method Summary

Modifier and Type	Method and Description
Asset	acquireAsset(String childName) Get or create an asset under this one.
default <V> V	acquireView(Class<V> viewType) Get or create a view with out a RequestContext.
<V> V	acquireView(Class<V> viewType, RequestContext requestContext) Get or create a view based on a RequestContext.
default <V> V	acquireView(RequestContext requestContext) Get or create a view based on a RequestContext.
<V> void	addLeafRule(Class<V> viewType, String description, LeafViewFactory<V> factory) Add a rule or factory for creating view on demand.
<V> V	addView(Class<V> viewType, V view) Add an implementation of a view to the asset..
<V,U> void	addWrappingRule(Class<V> viewType, String description, java.util.function.BiPredicate<RequestContext,Asset> predicate, WrappingViewFactory<V,U> factory, Class<U> underlyingType) Add a rule or factory for creating views on demand.
<V,U> void	addWrappingRule(Class<V> viewType, String description, WrappingViewFactory<V,U> factory, Class<U> underlyingType) Add a rule or factory for creating views on demand.
default Asset	findAsset(String name) Search a tree to find the first Asset with the name given.
default <V> V	findOrCreateView(Class<V> viewType) Search up the tree for a view of viewType.
default <V> V	findView(Class<V> viewType) Search for a view up the tree.
void	forEachChild(net.openhft.chronicle.core.util.ThrowingAcceptor<Asset,InvalidSubscriberException> childAcceptor) Iterate of all the children of this Asset.
default String	fullName()
default Asset	getAsset(String fullName) Navigate down the tree to find an asset.
Asset	getChild(String name) Get the child of an asset.
<V> V	getView(Class<V> viewType) Get a view if it already exists on the current Asset.
boolean	hasChildren() Is this a leaf node.
<V> boolean	hasFactoryFor(Class<V> viewType) Determine when an asset has a factory/rule for a viewType type.
boolean	isSubAsset()
String	name()
Asset	parent()
<V> void	registerView(Class<V> viewType, V view) Provide a specific implementation of a view
void	removeChild(String name) Remove a child asset from the tree.
default Asset	root() Find the root Asset for this tree.
Subscription	subscription(boolean createIfAbsent) Obtain the default subscription view.

Methods inherited from interface net.openhft.chronicle.core.io.Closeable

close, closeQuietly

Method Detail

name

String name()

Returns:

the name of this asset (not including the group)

parent

@Nullable
Asset parent()

Returns:

the parent of this asset or null if it is the root.

fullName

@NotNull
default String fullName()

Returns:

the full name of this asset including it's parent and theirs etc.

subscription

Subscription subscription(boolean createIfAbsent)
                   throws AssetNotFoundException

Obtain the default subscription view. If there is more than one this will be the object subscription view.

Parameters:

createIfAbsent - create one if it doesn't exist.

Returns:

the Subscription

Throws:

AssetNotFoundException - if the Subscription doesn't exist and the tree is not able to create the Subscription.

getAsset

@Nullable
default Asset getAsset(@NotNull
                                 String fullName)

Navigate down the tree to find an asset.

Parameters:

fullName - with names separated by /

Returns:

the Asset found or null

acquireAsset

@NotNull
Asset acquireAsset(String childName)
                     throws AssetNotFoundException

Get or create an asset under this one.

Parameters:

childName - name of the child asset.

Returns:

Throws:

AssetNotFoundException

findAsset

@Nullable
default Asset findAsset(@NotNull
                                  String name)

Search a tree to find the first Asset with the name given.

Parameters:

name - partial name of asset to find.

Returns:

the Asset found or null.

findView

@Nullable
default <V> V findView(@NotNull
                                 Class<V> viewType)

Search for a view up the tree.

Parameters:

viewType - the class pf the view

Returns:

the View found or null.

findOrCreateView

@Nullable
default <V> V findOrCreateView(@NotNull
                                         Class<V> viewType)
                                  throws AssetNotFoundException

Search up the tree for a view of viewType. If one doesn't exist find a factory and add it to the asset the factory is associated with. This view can then be shared for the Assets under the Asset where the factory is defined.

Parameters:

viewType - to obtain.

Returns:

the view it could be created

Throws:

AssetNotFoundException

hasFactoryFor

<V> boolean hasFactoryFor(Class<V> viewType)

Determine when an asset has a factory/rule for a viewType type.

Parameters:

viewType - to look for.

Returns:

true, if the factory can be found, or false if not.

getChild

Asset getChild(String name)

Get the child of an asset.

Parameters:

name - of the child.

Returns:

the Asset or null if it doesn't exist.

removeChild

void removeChild(String name)

Remove a child asset from the tree.

Parameters:

name - of the child to remove.

acquireView

@NotNull
default <V> V acquireView(@NotNull
                                   RequestContext requestContext)
                            throws AssetNotFoundException

Get or create a view based on a RequestContext. First it looks for a matching viewType(). If found this is returned.

Parameters:

requestContext - to use in the construction of the view

Returns:

the View obtained.

Throws:

AssetNotFoundException - if the Asset could not be created. This can happen if a required rule is not provided.

acquireView

@NotNull
<V> V acquireView(Class<V> viewType,
                           RequestContext requestContext)
                    throws AssetNotFoundException

Get or create a view based on a RequestContext. First it looks for a matching viewType(). If found this is returned. The viewType given overrides the type provided in the RequestContext.

Parameters:

viewType - to obtain.

requestContext - to use in the construction of the view

Returns:

the View obtained.

Throws:

AssetNotFoundException - if the Asset could not be created. This can happen if a required rule is not provided.

acquireView

@NotNull
default <V> V acquireView(Class<V> viewType)

Get or create a view with out a RequestContext. First it looks for a matching viewType(). If found this is returned. The viewType given overrides the type provided in the RequestContext.

Parameters:

viewType - to obtain.

Returns:

the View obtained.

Throws:

AssetNotFoundException - if the Asset could not be created. This can happen if a required rule is not provided.

getView

@Nullable
<V> V getView(Class<V> viewType)

Get a view if it already exists on the current Asset.

Parameters:

viewType - the associated interface or class for this view.

Returns:

a view which implements viewType, or null if it doesn't exist.

registerView

<V> void registerView(Class<V> viewType,
                      V view)

Provide a specific implementation of a view

Parameters:

viewType - interface or class to associate this implementation with.

view - implementation of viewType to use.

addLeafRule

<V> void addLeafRule(Class<V> viewType,
                     String description,
                     LeafViewFactory<V> factory)

Add a rule or factory for creating view on demand. A Leaf rule doesn't need any view to exist before you create it. This can be used for building the fundamental data structure which represents this Asset.

If two rules with the same description are provided, the new factory will replace the old. At present, any new factory replaces the old one, however in the future we may support multiple factories.

Parameters:

viewType - interface to associate this factory with.

description - of the factory

factory - to create a viewType

addWrappingRule

<V,U> void addWrappingRule(Class<V> viewType,
                           String description,
                           WrappingViewFactory<V,U> factory,
                           Class<U> underlyingType)

Add a rule or factory for creating views on demand. A Wrapping Rule need an underlying view to wrap before it can be created. This can be used for laying functionality on existing views.

If two rules with the same description are provided, the new factory replaces the old one. Note: if rules with different descriptions are provided, they are called in ASCIIbetical order of the description.

If a factory returns null, a later factory will be called.

Parameters:

viewType - class of the view.

description - to use to comment on the view, determine order of factories and detect dupliates.

factory - to use to create the view. If the factory returns null, the next factory is called.

underlyingType - the underlying view type required.

addWrappingRule

<V,U> void addWrappingRule(Class<V> viewType,
                           String description,
                           java.util.function.BiPredicate<RequestContext,Asset> predicate,
                           WrappingViewFactory<V,U> factory,
                           Class<U> underlyingType)

Add a rule or factory for creating views on demand. A Wrapping Rule need an underlying view to wrap before it can be created. This can be used for laying functionality on existing views.

If two rules with the same description are provided, the new factory replaces the old one. Note: if rules with different descriptions are provided, they are called in ASCIIbetical order of the description.

If the predictae returns false or a factory returns null, a later factory will be called.

Parameters:

viewType - class of the view.

description - to use to comment on the view, determine order of factories and detect dupliates.

predicate - to test whether this factory applies.

factory - to use to create the view. If the factory returns null, the next factory is called.

underlyingType - the underlying view type required.

addView

<V> V addView(Class<V> viewType,
              V view)

Add an implementation of a view to the asset.. This can be used instead of, or in addition to adding rules.

Parameters:

viewType - to associate this implementation with.

view -

Returns:

the view provided.

isSubAsset

boolean isSubAsset()

Returns:

true if this is a simplified Asset atteched to a keyed Asset. E.g. if you subscribe to a key in a Map this key uses a SubAsset.

root

@NotNull
default Asset root()

Find the root Asset for this tree.

Returns:

the root.

hasChildren

boolean hasChildren()

Is this a leaf node.

Returns:

if this Asset has Asset as children.

forEachChild

void forEachChild(net.openhft.chronicle.core.util.ThrowingAcceptor<Asset,InvalidSubscriberException> childAcceptor)
           throws InvalidSubscriberException

Iterate of all the children of this Asset.

Parameters:

childAcceptor - to accept each child.

Throws:

InvalidSubscriberException - to throw if the accept is no longer interested in getting more children.