| /* |
| * 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.apache.tinkerpop.gremlin.process.traversal.step.util; |
| |
| import java.io.Serializable; |
| import java.util.*; |
| |
| /** |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| */ |
| public class Tree<T> extends HashMap<T, Tree<T>> implements Serializable { |
| |
| public Tree() { |
| super(); |
| } |
| |
| @SafeVarargs |
| public Tree(final T... children) { |
| this(); |
| for (final T t : children) { |
| this.put(t, new Tree<>()); |
| } |
| } |
| |
| @SafeVarargs |
| public Tree(final Map.Entry<T, Tree<T>>... children) { |
| this(); |
| for (final Map.Entry<T, Tree<T>> entry : children) { |
| this.put(entry.getKey(), entry.getValue()); |
| } |
| } |
| |
| |
| public List<Tree<T>> getTreesAtDepth(final int depth) { |
| List<Tree<T>> currentDepth = Collections.singletonList(this); |
| for (int i = 0; i < depth; i++) { |
| if (i == depth - 1) { |
| return currentDepth; |
| } else { |
| final List<Tree<T>> temp = new ArrayList<Tree<T>>(); |
| for (final Tree<T> t : currentDepth) { |
| temp.addAll(t.values()); |
| } |
| currentDepth = temp; |
| } |
| } |
| return Collections.emptyList(); |
| } |
| |
| public List<T> getObjectsAtDepth(final int depth) { |
| final List<T> list = new ArrayList<T>(); |
| for (final Tree<T> t : this.getTreesAtDepth(depth)) { |
| list.addAll(t.keySet()); |
| } |
| return list; |
| } |
| |
| public List<Tree<T>> getLeafTrees() { |
| final List<Tree<T>> leaves = new ArrayList<>(); |
| List<Tree<T>> currentDepth = Collections.singletonList(this); |
| boolean allLeaves = false; |
| while (!allLeaves) { |
| allLeaves = true; |
| final List<Tree<T>> temp = new ArrayList<>(); |
| for (final Tree<T> t : currentDepth) { |
| if (t.isLeaf()) { |
| for (Map.Entry<T, Tree<T>> t2 : t.entrySet()) { |
| leaves.add(new Tree<T>(t2)); |
| } |
| } else { |
| allLeaves = false; |
| temp.addAll(t.values()); |
| } |
| } |
| currentDepth = temp; |
| |
| } |
| return leaves; |
| } |
| |
| public List<T> getLeafObjects() { |
| final List<T> leaves = new ArrayList<T>(); |
| for (final Tree<T> t : this.getLeafTrees()) { |
| leaves.addAll(t.keySet()); |
| } |
| return leaves; |
| } |
| |
| public boolean isLeaf() { |
| final Collection<Tree<T>> values = this.values(); |
| return values.iterator().next().isEmpty(); |
| |
| } |
| |
| public void addTree(final Tree<T> tree) { |
| tree.forEach((k, t) -> { |
| if (this.containsKey(k)) { |
| this.get(k).addTree(t); |
| } else { |
| this.put(k, t); |
| } |
| }); |
| } |
| |
| public List<Tree<T>> splitParents() { |
| if (this.keySet().size() == 1) { |
| return Collections.singletonList(this); |
| } else { |
| final List<Tree<T>> parents = new ArrayList<>(); |
| this.forEach((k, t) -> { |
| final Tree<T> parentTree = new Tree<>(); |
| parentTree.put(k, t); |
| parents.add(parentTree); |
| }); |
| return parents; |
| } |
| } |
| } |