2 * ============LICENSE_START=======================================================
4 * ================================================================================
5 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
6 * ================================================================================
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 * ============LICENSE_END=========================================================
21 package org.openecomp.modelloader.entity.model;
23 import jline.internal.Log;
25 import org.openecomp.modelloader.entity.Artifact;
27 import java.util.ArrayList;
28 import java.util.Collection;
29 import java.util.HashMap;
30 import java.util.HashSet;
31 import java.util.Iterator;
32 import java.util.List;
35 * Utility class to sort the given Models according to their dependencies.
36 * Example: Given a list of Models [A, B, C] where B depends on A, and A depends
37 * on C, the sorted result will be [C, A, B]
39 public class ModelSorter {
42 * Wraps a Model object to form dependencies other Models using Edges.
45 private final ModelArtifact model;
46 private final HashSet<Edge> inEdges;
47 private final HashSet<Edge> outEdges;
49 public Node(ModelArtifact model) {
51 inEdges = new HashSet<Edge>();
52 outEdges = new HashSet<Edge>();
55 public Node addEdge(Node node) {
56 Edge edge = new Edge(this, node);
58 node.inEdges.add(edge);
63 public String toString() {
64 return model.getNameVersionId();
68 public boolean equals(Object other) {
69 ModelArtifact otherModel = ((Node) other).model;
70 return this.model.getNameVersionId().equals(otherModel.getNameVersionId());
74 public int hashCode() {
75 return this.model.getNameVersionId().hashCode();
81 * Represents a dependency between two Nodes.
84 public final Node from;
87 public Edge(Node from, Node to) {
93 public boolean equals(Object obj) {
94 Edge edge = (Edge) obj;
95 return edge.from == from && edge.to == to;
100 * Returns the list of models sorted by order of dependency.
102 * @param originalList
103 * the list that needs to be sorted
104 * @return a list of sorted models
106 public List<Artifact> sort(List<Artifact> originalList) {
108 if (originalList.size() <= 1) {
112 Collection<Node> nodes = createNodes(originalList);
113 Collection<Node> sortedNodes = sortNodes(nodes);
115 List<Artifact> sortedModelsList = new ArrayList<Artifact>(sortedNodes.size());
116 for (Node node : sortedNodes) {
117 sortedModelsList.add(node.model);
120 return sortedModelsList;
124 * Create nodes from the list of models and their dependencies.
127 * what the nodes creation is based upon
128 * @return Collection of Node objects
130 private Collection<Node> createNodes(Collection<Artifact> models) {
132 // load list of models into a map, so we can later replace referenceIds with
134 HashMap<String, ModelArtifact> versionIdToModelMap = new HashMap<String, ModelArtifact>();
135 for (Artifact art : models) {
136 ModelArtifact ma = (ModelArtifact) art;
137 versionIdToModelMap.put(ma.getNameVersionId(), ma);
140 HashMap<String, Node> nodes = new HashMap<String, Node>();
141 // create a node for each model and its referenced models
142 for (Artifact art : models) {
143 ModelArtifact model = (ModelArtifact) art;
145 // node might have been created by another model referencing it
146 Node node = nodes.get(model.getNameVersionId());
149 node = new Node(model);
150 nodes.put(model.getNameVersionId(), node);
153 for (String referencedModelId : model.getDependentModelIds()) {
154 // node might have been created by another model referencing it
155 Node referencedNode = nodes.get(referencedModelId);
157 if (null == referencedNode) {
159 ModelArtifact referencedModel = versionIdToModelMap.get(referencedModelId);
160 if (referencedModel == null) {
161 Log.debug("ignoring " + referencedModelId);
162 continue; // referenced model not supplied, no need to sort it
164 referencedNode = new Node(referencedModel);
165 nodes.put(referencedModelId, referencedNode);
167 referencedNode.addEdge(node);
171 return nodes.values();
175 * Sorts the given Nodes by order of dependency.
177 * @param originalList
178 * the collection of nodes to be sorted
179 * @return a sorted collection of the given nodes
181 private Collection<Node> sortNodes(Collection<Node> unsortedNodes) {
183 // L <- Empty list that will contain the sorted elements
184 ArrayList<Node> nodeList = new ArrayList<Node>();
186 // S <- Set of all nodes with no incoming edges
187 HashSet<Node> nodeSet = new HashSet<Node>();
188 for (Node unsortedNode : unsortedNodes) {
189 if (unsortedNode.inEdges.size() == 0) {
190 nodeSet.add(unsortedNode);
194 // while S is non-empty do
195 while (!nodeSet.isEmpty()) {
196 // remove a node n from S
197 Node node = nodeSet.iterator().next();
198 nodeSet.remove(node);
203 // for each node m with an edge e from n to m do
204 for (Iterator<Edge> it = node.outEdges.iterator(); it.hasNext();) {
205 // remove edge e from the graph
206 Edge edge = it.next();
208 it.remove();// Remove edge from n
209 to.inEdges.remove(edge);// Remove edge from m
211 // if m has no other incoming edges then insert m into S
212 if (to.inEdges.isEmpty()) {
217 // Check to see if all edges are removed
218 boolean cycle = false;
219 for (Node node : unsortedNodes) {
220 if (!node.inEdges.isEmpty()) {
226 throw new RuntimeException(
227 "Circular dependency present between models, topological sort not possible");