View Javadoc
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.apache.maven.api;
20  
21  import java.util.List;
22  import java.util.Optional;
23  import java.util.function.Predicate;
24  import java.util.stream.Stream;
25  import org.apache.maven.api.annotations.Experimental;
26  import org.apache.maven.api.annotations.Immutable;
27  import org.apache.maven.api.annotations.Nonnull;
28  
29  /**
30   * Represents a dependency node within a Maven project's dependency collector.
31   *
32   * @since 4.0
33   * @see org.apache.maven.api.services.DependencyCollectorResult#getRoot()
34   */
35  @Experimental
36  @Immutable
37  public interface Node {
38  
39      /**
40       * @return dependency for this node
41       */
42      Dependency getDependency();
43  
44      /**
45       * Gets the child nodes of this node.
46       *
47       * @return the child nodes of this node, never {@code null}
48       */
49      @Nonnull
50      List<Node> getChildren();
51  
52      /**
53       * @return repositories of this node
54       */
55      @Nonnull
56      List<RemoteRepository> getRemoteRepositories();
57  
58      /**
59       * The repository where this artifact has been downloaded from.
60       */
61      @Nonnull
62      Optional<RemoteRepository> getRepository();
63  
64      /**
65       * Traverses this node and potentially its children using the specified visitor.
66       *
67       * @param visitor the visitor to call back, must not be {@code null}
68       * @return {@code true} to visit siblings nodes of this node as well, {@code false} to skip siblings
69       */
70      boolean accept(@Nonnull NodeVisitor visitor);
71  
72      /**
73       * Returns a new tree starting at this node, filtering the children.
74       * Note that this node will not be filtered and only the children
75       * and its descendant will be checked.
76       *
77       * @param filter the filter to apply
78       * @return a new filtered graph
79       */
80      Node filter(Predicate<Node> filter);
81  
82      /**
83       * Returns a string representation of this dependency node.
84       *
85       * @return the string representation
86       */
87      String asString();
88  
89      /**
90       * Obtain a Stream containing this node and all its descendant.
91       *
92       * @return a stream containing this node and its descendant
93       */
94      @Nonnull
95      default Stream<Node> stream() {
96          return Stream.concat(Stream.of(this), getChildren().stream().flatMap(Node::stream));
97      }
98  }