--- /dev/null
+/*-
+ * ============LICENSE_START=======================================================
+ * MODEL LOADER SERVICE
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.modelloader.entity.model;
+
+import jline.internal.Log;
+
+import org.openecomp.modelloader.entity.Artifact;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * Utility class to sort the given Models according to their dependencies.
+ * Example: Given a list of Models [A, B, C] where B depends on A, and A depends
+ * on C, the sorted result will be [C, A, B]
+ */
+public class ModelSorter {
+
+ /**
+ * Wraps a Model object to form dependencies other Models using Edges.
+ */
+ static class Node {
+ private final ModelArtifact model;
+ private final HashSet<Edge> inEdges;
+ private final HashSet<Edge> outEdges;
+
+ public Node(ModelArtifact model) {
+ this.model = model;
+ inEdges = new HashSet<Edge>();
+ outEdges = new HashSet<Edge>();
+ }
+
+ public Node addEdge(Node node) {
+ Edge edge = new Edge(this, node);
+ outEdges.add(edge);
+ node.inEdges.add(edge);
+ return this;
+ }
+
+ @Override
+ public String toString() {
+ return model.getNameVersionId();
+ }
+
+ @Override
+ public boolean equals(Object other) {
+ ModelArtifact otherModel = ((Node) other).model;
+ return this.model.getNameVersionId().equals(otherModel.getNameVersionId());
+ }
+
+ @Override
+ public int hashCode() {
+ return this.model.getNameVersionId().hashCode();
+
+ }
+ }
+
+ /**
+ * Represents a dependency between two Nodes.
+ */
+ static class Edge {
+ public final Node from;
+ public final Node to;
+
+ public Edge(Node from, Node to) {
+ this.from = from;
+ this.to = to;
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ Edge edge = (Edge) obj;
+ return edge.from == from && edge.to == to;
+ }
+ }
+
+ /**
+ * Returns the list of models sorted by order of dependency.
+ *
+ * @param originalList
+ * the list that needs to be sorted
+ * @return a list of sorted models
+ */
+ public List<Artifact> sort(List<Artifact> originalList) {
+
+ if (originalList.size() <= 1) {
+ return originalList;
+ }
+
+ Collection<Node> nodes = createNodes(originalList);
+ Collection<Node> sortedNodes = sortNodes(nodes);
+
+ List<Artifact> sortedModelsList = new ArrayList<Artifact>(sortedNodes.size());
+ for (Node node : sortedNodes) {
+ sortedModelsList.add(node.model);
+ }
+
+ return sortedModelsList;
+ }
+
+ /**
+ * Create nodes from the list of models and their dependencies.
+ *
+ * @param models
+ * what the nodes creation is based upon
+ * @return Collection of Node objects
+ */
+ private Collection<Node> createNodes(Collection<Artifact> models) {
+
+ // load list of models into a map, so we can later replace referenceIds with
+ // real Models
+ HashMap<String, ModelArtifact> versionIdToModelMap = new HashMap<String, ModelArtifact>();
+ for (Artifact art : models) {
+ ModelArtifact ma = (ModelArtifact) art;
+ versionIdToModelMap.put(ma.getNameVersionId(), ma);
+ }
+
+ HashMap<String, Node> nodes = new HashMap<String, Node>();
+ // create a node for each model and its referenced models
+ for (Artifact art : models) {
+ ModelArtifact model = (ModelArtifact) art;
+
+ // node might have been created by another model referencing it
+ Node node = nodes.get(model.getNameVersionId());
+
+ if (null == node) {
+ node = new Node(model);
+ nodes.put(model.getNameVersionId(), node);
+ }
+
+ for (String referencedModelId : model.getDependentModelIds()) {
+ // node might have been created by another model referencing it
+ Node referencedNode = nodes.get(referencedModelId);
+
+ if (null == referencedNode) {
+ // create node
+ ModelArtifact referencedModel = versionIdToModelMap.get(referencedModelId);
+ if (referencedModel == null) {
+ Log.debug("ignoring " + referencedModelId);
+ continue; // referenced model not supplied, no need to sort it
+ }
+ referencedNode = new Node(referencedModel);
+ nodes.put(referencedModelId, referencedNode);
+ }
+ referencedNode.addEdge(node);
+ }
+ }
+
+ return nodes.values();
+ }
+
+ /**
+ * Sorts the given Nodes by order of dependency.
+ *
+ * @param originalList
+ * the collection of nodes to be sorted
+ * @return a sorted collection of the given nodes
+ */
+ private Collection<Node> sortNodes(Collection<Node> unsortedNodes) {
+
+ // L <- Empty list that will contain the sorted elements
+ ArrayList<Node> nodeList = new ArrayList<Node>();
+
+ // S <- Set of all nodes with no incoming edges
+ HashSet<Node> nodeSet = new HashSet<Node>();
+ for (Node unsortedNode : unsortedNodes) {
+ if (unsortedNode.inEdges.size() == 0) {
+ nodeSet.add(unsortedNode);
+ }
+ }
+
+ // while S is non-empty do
+ while (!nodeSet.isEmpty()) {
+ // remove a node n from S
+ Node node = nodeSet.iterator().next();
+ nodeSet.remove(node);
+
+ // insert n into L
+ nodeList.add(node);
+
+ // for each node m with an edge e from n to m do
+ for (Iterator<Edge> it = node.outEdges.iterator(); it.hasNext();) {
+ // remove edge e from the graph
+ Edge edge = it.next();
+ Node to = edge.to;
+ it.remove();// Remove edge from n
+ to.inEdges.remove(edge);// Remove edge from m
+
+ // if m has no other incoming edges then insert m into S
+ if (to.inEdges.isEmpty()) {
+ nodeSet.add(to);
+ }
+ }
+ }
+ // Check to see if all edges are removed
+ boolean cycle = false;
+ for (Node node : unsortedNodes) {
+ if (!node.inEdges.isEmpty()) {
+ cycle = true;
+ break;
+ }
+ }
+ if (cycle) {
+ throw new RuntimeException(
+ "Circular dependency present between models, topological sort not possible");
+ }
+
+ return nodeList;
+ }
+
+}
Code Review / aai / model-loader.git / blobdiff