package org.eclipse.aether.collection;

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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import org.eclipse.aether.RepositoryException;
import org.eclipse.aether.graph.DependencyNode;

Transforms a given dependency graph.

Note: Implementations must be stateless.

Warning: Dependency graphs may generally contain cycles. As such a graph transformer that cannot assume for
sure that cycles have already been eliminated must gracefully handle cyclic graphs, e.g. guard against infinite
recursion.
See Also:
getDependencyGraphTransformer.getDependencyGraphTransformer()/**
 * Transforms a given dependency graph.
 * <p>
 * <strong>Note:</strong> Implementations must be stateless.
 * <p>
 * <em>Warning:</em> Dependency graphs may generally contain cycles. As such a graph transformer that cannot assume for
 * sure that cycles have already been eliminated must gracefully handle cyclic graphs, e.g. guard against infinite
 * recursion.
 * 
 * @see org.eclipse.aether.RepositorySystemSession#getDependencyGraphTransformer()
 */
public interface DependencyGraphTransformer
{

    
Transforms the dependency graph denoted by the specified root node. The transformer may directly change the
provided input graph or create a new graph, the former is recommended for performance reasons.
Params:
node – The root node of the (possibly cyclic!) graph to transform, must not be null.
context – The graph transformation context, must not be null.
Throws:
RepositoryException – If the transformation failed.
Returns:
The result graph of the transformation, never null./**
     * Transforms the dependency graph denoted by the specified root node. The transformer may directly change the
     * provided input graph or create a new graph, the former is recommended for performance reasons.
     * 
     * @param node The root node of the (possibly cyclic!) graph to transform, must not be {@code null}.
     * @param context The graph transformation context, must not be {@code null}.
     * @return The result graph of the transformation, never {@code null}.
     * @throws RepositoryException If the transformation failed.
     */
    DependencyNode transformGraph( DependencyNode node, DependencyGraphTransformationContext context )
        throws RepositoryException;

}