/*
* Copyright 2014 the original author or authors.
*
* Licensed 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.gradle.api.internal.artifacts.ivyservice.resolveengine.graph;
/**
* Receives the result of dependency graph resolution, as a series of events.
*
* Implementations should make copies of whatever state they need to retain.
*/
public interface DependencyGraphVisitor {
/**
* Starts traversal of the graph.
*/
void start(DependencyGraphNode root);
/**
* Visits a node of the graph. Includes the root. This method is called for all nodes before {@link #visitEdges(DependencyGraphNode)} is called.
* Nodes are visited in consumer-first order.
*/
void visitNode(DependencyGraphNode node);
/**
* Visits a selector. This method is called for all selectors before {@link #visitEdges(DependencyGraphNode)} is called.
*/
void visitSelector(DependencyGraphSelector selector);
/**
* Visits edges to/from a node of the graph. Includes the root. This method is called for all nodes after {@link #visitNode(DependencyGraphNode)} has been called for all nodes.
*/
void visitEdges(DependencyGraphNode node);
/**
* Completes traversal of the graph.
*/
void finish(DependencyGraphNode root);
DependencyGraphVisitor NO_OP = new DependencyGraphVisitor() {
@Override
public void start(DependencyGraphNode root) {
}
@Override
public void visitNode(DependencyGraphNode node) {
}
@Override
public void visitSelector(DependencyGraphSelector selector) {
}
@Override
public void visitEdges(DependencyGraphNode node) {
}
@Override
public void finish(DependencyGraphNode root) {
}
};
}