1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.eclipse.aether.collection;
20
21 import org.eclipse.aether.RepositoryException;
22 import org.eclipse.aether.graph.DependencyNode;
23
24 /**
25 * Transforms a given dependency graph.
26 * <p>
27 * <strong>Note:</strong> Implementations must be stateless.
28 * <p>
29 * <em>Warning:</em> Dependency graphs may generally contain cycles. As such a graph transformer that cannot assume for
30 * sure that cycles have already been eliminated must gracefully handle cyclic graphs, e.g. guard against infinite
31 * recursion.
32 *
33 * @see org.eclipse.aether.RepositorySystemSession#getDependencyGraphTransformer()
34 */
35 public interface DependencyGraphTransformer {
36
37 /**
38 * Transforms the dependency graph denoted by the specified root node. The transformer may directly change the
39 * provided input graph or create a new graph, the former is recommended for performance reasons.
40 *
41 * @param node The root node of the (possibly cyclic!) graph to transform, must not be {@code null}.
42 * @param context The graph transformation context, must not be {@code null}.
43 * @return The result graph of the transformation, never {@code null}.
44 * @throws RepositoryException If the transformation failed.
45 */
46 DependencyNode transformGraph(DependencyNode node, DependencyGraphTransformationContext context)
47 throws RepositoryException;
48 }