org.eclipse.aether.util.graph.visitor.CloningDependencyVisitor Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of spring-cloud-contract-shade Show documentation
Show all versions of spring-cloud-contract-shade Show documentation
Spring Cloud Contract Shaded Dependencies
/*
* 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.
*/
package org.eclipse.aether.util.graph.visitor;
import java.util.IdentityHashMap;
import java.util.Map;
import org.eclipse.aether.graph.DefaultDependencyNode;
import org.eclipse.aether.graph.DependencyNode;
import org.eclipse.aether.graph.DependencyVisitor;
/**
* A dependency visitor that constructs a clone of the visited dependency graph. If such a visitor is passed into a
* {@link FilteringDependencyVisitor}, a sub graph can be created. This class creates shallow clones of the visited
* dependency nodes (via {@link DefaultDependencyNode#DefaultDependencyNode(DependencyNode)}) but clients can create a
* subclass and override {@link #clone(DependencyNode)} to alter the clone process.
*/
public class CloningDependencyVisitor implements DependencyVisitor {
private final Map clones;
private final Stack parents;
private DependencyNode root;
/**
* Creates a new visitor that clones the visited nodes.
*/
public CloningDependencyVisitor() {
parents = new Stack<>();
clones = new IdentityHashMap<>(256);
}
/**
* Gets the root node of the cloned dependency graph.
*
* @return The root node of the cloned dependency graph or {@code null}.
*/
public final DependencyNode getRootNode() {
return root;
}
/**
* Creates a clone of the specified node.
*
* @param node The node to clone, must not be {@code null}.
* @return The cloned node, never {@code null}.
*/
protected DependencyNode clone(DependencyNode node) {
return new DefaultDependencyNode(node);
}
@Override
public final boolean visitEnter(DependencyNode node) {
boolean recurse = true;
DependencyNode clone = clones.get(node);
if (clone == null) {
clone = clone(node);
clones.put(node, clone);
} else {
recurse = false;
}
DependencyNode parent = parents.peek();
if (parent == null) {
root = clone;
} else {
parent.getChildren().add(clone);
}
parents.push(clone);
return recurse;
}
@Override
public final boolean visitLeave(DependencyNode node) {
parents.pop();
return true;
}
}