Package org.eclipse.aether.util.graph.transformer

Class ConflictResolver.VersionSelector

java.lang.Object

org.eclipse.aether.util.graph.transformer.ConflictResolver.VersionSelector

Direct Known Subclasses:

NearestVersionSelector

Enclosing class:

ConflictResolver

public abstract static class ConflictResolver.VersionSelector
extends Object

An extension point of ConflictResolver that determines the winner among conflicting dependencies. The winning node (and its children) will be retained in the dependency graph, the other nodes will get removed. The version selector does not need to deal with potential scope conflicts, these will be addressed afterwards by the ConflictResolver.ScopeSelector.

Note: Implementations must be stateless.

Constructor Summary

Constructors

Constructor	Description
VersionSelector()

Method Summary

Modifier and Type	Method	Description
ConflictResolver.VersionSelector	getInstance(DependencyNode root, DependencyGraphTransformationContext context)	Retrieves the version selector for use during the specified graph transformation.
abstract void	selectVersion(ConflictResolver.ConflictContext context)	Determines the winning node among conflicting dependencies.

Methods inherited from class java.lang.Object

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

Constructor Detail

VersionSelector

public VersionSelector()

Method Detail

getInstance

public ConflictResolver.VersionSelector getInstance(DependencyNode root,
                                                    DependencyGraphTransformationContext context)
                                             throws RepositoryException

Retrieves the version selector for use during the specified graph transformation. The conflict resolver calls this method once per ConflictResolver.transformGraph(DependencyNode, DependencyGraphTransformationContext) invocation to allow implementations to prepare any auxiliary data that is needed for their operation. Given that implementations must be stateless, a new instance needs to be returned to hold such auxiliary data. The default implementation simply returns the current instance which is appropriate for implementations which do not require auxiliary data.

Parameters:

root - The root node of the (possibly cyclic!) graph to transform, must not be null.

context - The graph transformation context, must not be null.

Returns:

The scope deriver to use for the given graph transformation, never null.

Throws:

RepositoryException - If the instance could not be retrieved.

selectVersion

public abstract void selectVersion(ConflictResolver.ConflictContext context)
                            throws RepositoryException

Determines the winning node among conflicting dependencies. Implementations will usually iterate ConflictResolver.ConflictContext.getItems(), inspect ConflictResolver.ConflictItem.getNode() and eventually call ConflictResolver.ConflictContext.setWinner(ConflictResolver.ConflictItem) to deliver the winner. Failure to select a winner will automatically fail the entire conflict resolution.

Parameters:

context - The conflict context, must not be null.

Throws:

RepositoryException - If the version selection failed.