| package org.apache.maven.shared.dependency.graph.traversal; |
| |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| import java.util.ArrayList; |
| import java.util.Stack; |
| |
| import org.apache.maven.shared.dependency.graph.DependencyNode; |
| import org.apache.maven.shared.dependency.graph.internal.DefaultDependencyNode; |
| |
| /** |
| * A dependency node visitor that clones visited nodes into a new dependency tree. This can be used in conjunction with |
| * a dependency node filter to construct subtrees. |
| * |
| * @author <a href="mailto:markhobson@gmail.com">Mark Hobson</a> |
| */ |
| public class BuildingDependencyNodeVisitor |
| implements DependencyNodeVisitor |
| { |
| // fields ----------------------------------------------------------------- |
| |
| /** |
| * The dependency node visitor to apply on the resultant dependency tree, or <code>null</code> for none. |
| */ |
| private final DependencyNodeVisitor visitor; |
| |
| /** |
| * The resultant tree parent nodes for the currently visited node. |
| */ |
| private final Stack<DependencyNode> parentNodes; |
| |
| /** |
| * The root node of the resultant tree. |
| */ |
| private DependencyNode rootNode; |
| |
| // constructors ----------------------------------------------------------- |
| |
| /** |
| * Creates a dependency node visitor that clones visited nodes into a new dependency tree. |
| */ |
| public BuildingDependencyNodeVisitor() |
| { |
| this( null ); |
| } |
| |
| /** |
| * Creates a dependency node visitor that clones visited nodes into a new dependency tree, and then applies the |
| * specified dependency node visitor on the resultant dependency tree. |
| * |
| * @param visitor |
| * the dependency node visitor to apply on the resultant dependency tree, or <code>null</code> for none |
| */ |
| public BuildingDependencyNodeVisitor( DependencyNodeVisitor visitor ) |
| { |
| this.visitor = visitor; |
| |
| parentNodes = new Stack<DependencyNode>(); |
| } |
| |
| // DependencyNodeVisitor methods ------------------------------------------ |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean visit( DependencyNode node ) |
| { |
| // clone the node |
| DefaultDependencyNode newNode = |
| new DefaultDependencyNode( parentNodes.isEmpty() ? null : parentNodes.peek(), node.getArtifact(), |
| node.getPremanagedScope(), node.getPremanagedVersion(), |
| node.getVersionConstraint() ); |
| newNode.setChildren( new ArrayList<DependencyNode>() ); |
| |
| if ( parentNodes.empty() ) |
| { |
| rootNode = newNode; |
| } |
| else |
| { |
| DependencyNode parentNode = parentNodes.peek(); |
| parentNode.getChildren().add( newNode ); |
| } |
| |
| parentNodes.push( newNode ); |
| |
| return true; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean endVisit( DependencyNode node ) |
| { |
| parentNodes.pop(); |
| |
| // apply the visitor to the resultant tree on the last visit |
| if ( parentNodes.empty() && visitor != null ) |
| { |
| rootNode.accept( visitor ); |
| } |
| |
| return true; |
| } |
| |
| // public methods --------------------------------------------------------- |
| |
| /** |
| * Gets the dependency node visitor that this visitor applies on the resultant dependency tree. |
| * |
| * @return the dependency node visitor, or <code>null</code> for none |
| */ |
| public DependencyNodeVisitor getDependencyNodeVisitor() |
| { |
| return visitor; |
| } |
| |
| /** |
| * Gets the root node of the resultant dependency tree constructed by this visitor. |
| * |
| * @return the root node, or <code>null</code> if the source tree has not yet been visited |
| */ |
| public DependencyNode getDependencyTree() |
| { |
| return rootNode; |
| } |
| } |