2 * ============LICENSE_START=======================================================
4 * ================================================================================
5 * Copyright © 2017-2018 AT&T Intellectual Property. All rights reserved.
6 * Copyright © 2017-2018 Amdocs
7 * ================================================================================
8 * Licensed under the Apache License, Version 2.0 (the "License");
9 * you may not use this file except in compliance with the License.
10 * You may obtain a copy of the License at
12 * http://www.apache.org/licenses/LICENSE-2.0
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 * ============LICENSE_END=========================================================
21 package org.onap.aai.datarouter.util;
23 import java.util.ArrayList;
24 import java.util.List;
26 public class SearchSuggestionPermutation {
28 * Will return all the unique combinations of the suggestions provided.
29 * The order of the permutation is not taken into account when computing
31 * e.g.: A list of A,B,C,D will return
32 * [[A], [A, B, C, D], [A, C, D], [A, D], [B], [B, C, D], [B, D], [C], [C, D], [D]]
34 * @param list The list of statuses to create permutations of
35 * @return A list which contains a array list of all possible combinations
37 public static ArrayList<ArrayList<String>> getUniqueListForSuggestions(
38 List<String> originalList) {
39 ArrayList<ArrayList<String>> lists = new ArrayList<>();
40 if (originalList.isEmpty()) {
41 lists.add(new ArrayList<String>());
44 List<String> list = new ArrayList<>(originalList);
45 String head = list.get(0);
46 ArrayList<String> rest = new ArrayList<>(list.subList(1, list.size()));
48 for (ArrayList<String> activeList : getUniqueListForSuggestions(rest)) {
49 ArrayList<String> newList = new ArrayList<>();
51 newList.addAll(activeList);
53 lists.add(activeList);
58 public static ArrayList<ArrayList<String>> getNonEmptyUniqueLists(List<String> list) {
59 ArrayList<ArrayList<String>> lists = getUniqueListForSuggestions(list);
60 // remove empty list from the power set
61 for (ArrayList<String> emptyList : lists) {
62 if (emptyList.isEmpty()) {
63 lists.remove(emptyList);
70 public static List<List<String>> getListPermutations(List<String> list) {
71 List<String> inputList = new ArrayList<>();
72 inputList.addAll(list);
73 if (inputList.isEmpty()) {
74 List<List<String>> result = new ArrayList<>();
75 result.add(new ArrayList<String>());
79 List<List<String>> listOfLists = new ArrayList<>();
81 String firstElement = inputList.remove(0);
83 List<List<String>> recursiveReturn = getListPermutations(inputList);
84 for (List<String> li : recursiveReturn) {
86 for (int index = 0; index <= li.size(); index++) {
87 List<String> temp = new ArrayList<>(li);
88 temp.add(index, firstElement);
89 listOfLists.add(temp);