org.grouplens.lenskit.inject

Class GraphtUtils

java.lang.Object

org.grouplens.lenskit.inject.GraphtUtils

public final class GraphtUtils
extends Object

Helper utilities for Grapht integration.

Since:

0.11

Field Summary

Fields

Modifier and Type	Field and Description
static Ordering<DAGEdge<Component,Dependency>>	DEP_EDGE_ORDER An ordering over dependency edges.

Method Summary

Modifier and Type	Method and Description
static void	checkForPlaceholders(DAGNode<Component,Dependency> graph, org.slf4j.Logger logger) Check a graph for placeholder satisfactions.
static boolean	desireIsTransient(Desire d) Determine whether a desire is transient.
static Predicate<DAGEdge<?,Dependency>>	edgeIsTransient()
static boolean	edgeIsTransient(DAGEdge<?,Dependency> input)
static DAGNode<Component,Dependency>	findSatisfyingNode(DAGNode<Component,Dependency> graph, QualifierMatcher qmatch, Class<?> type) Find a node with a satisfaction for a specified type.
static Set<DAGNode<Component,Dependency>>	getPlaceholderNodes(DAGNode<Component,Dependency> graph) Get the placeholder nodes from a graph.
static LinkedHashSet<DAGNode<Component,Dependency>>	getShareableNodes(DAGNode<Component,Dependency> graph) Find the set of shareable nodes (objects that will be replaced with instance satisfactions in the final graph).
static boolean	isShareable(DAGNode<Component,Dependency> node) Determine if a node is a shareable component.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEP_EDGE_ORDER

public static Ordering<DAGEdge<Component,Dependency>> DEP_EDGE_ORDER

An ordering over dependency edges.

Method Detail

checkForPlaceholders

public static void checkForPlaceholders(DAGNode<Component,Dependency> graph,
                                        org.slf4j.Logger logger)
                                 throws RecommenderConfigurationException

Check a graph for placeholder satisfactions.

Parameters:

graph - The graph to check.

Throws:

RecommenderConfigurationException - if the graph has a placeholder satisfaction.

getPlaceholderNodes

public static Set<DAGNode<Component,Dependency>> getPlaceholderNodes(DAGNode<Component,Dependency> graph)

Get the placeholder nodes from a graph.

Parameters:

graph - The graph.

Returns:

The set of nodes that have placeholder satisfactions.

isShareable

public static boolean isShareable(DAGNode<Component,Dependency> node)

Determine if a node is a shareable component.

Parameters:

node - The node.

Returns:

true if the component is shareable.

desireIsTransient

public static boolean desireIsTransient(@Nonnull
                                        Desire d)

Determine whether a desire is transient.

Parameters:

d - The desire to test.

Returns:

true if the desire is transient.

edgeIsTransient

public static boolean edgeIsTransient(DAGEdge<?,Dependency> input)

edgeIsTransient

public static Predicate<DAGEdge<?,Dependency>> edgeIsTransient()

getShareableNodes

public static LinkedHashSet<DAGNode<Component,Dependency>> getShareableNodes(DAGNode<Component,Dependency> graph)

Find the set of shareable nodes (objects that will be replaced with instance satisfactions in the final graph).

Parameters:

graph - The graph to analyze.

Returns:

The set of root nodes - nodes that need to be instantiated and removed. These nodes are in topologically sorted order.

findSatisfyingNode

@Nullable
public static DAGNode<Component,Dependency> findSatisfyingNode(DAGNode<Component,Dependency> graph,
                                                                         QualifierMatcher qmatch,
                                                                         Class<?> type)

Find a node with a satisfaction for a specified type. Does a breadth-first search to find the closest matching one.

Parameters:

type - The type to look for.

Returns:

A node whose satisfaction is compatible with type.

Review:

Decide how to handle qualifiers and contexts