Java List Uniqne Item uniqueList(List list)

Description

Make a copy of a list where the items are unique.

License

Apache License

Parameter

Parameter	Description
list	The list which may contain duplicates

Return

A new list containing only the unique items of the input list

Declaration

public static <T> List<T> uniqueList(List<T> list) 

Method Source Code

//package com.java2s;
/*//ww w . ja v  a 2 s.c om
 * Copyright 2013 Heads Up Development Ltd.
 *
 * 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.
 */

import java.util.ArrayList;

import java.util.List;

public class Main {
    /**
     * Make a copy of a list where the items are unique.
     *
     * @param list The list which may contain duplicates
     * @return A new list containing only the unique items of the input list
     */
    public static <T> List<T> uniqueList(List<T> list) {
        if (list == null) {
            return null;
        }

        List<T> unique = new ArrayList<T>(list.size());

        for (T next : list) {
            if (!unique.contains(next)) {
                unique.add(next);
            }
        }

        return unique;
    }
}

Related

1. unique(List array)
2. unique(List entities)
3. unique(List list)
4. uniqueList(Collection

   list)

5. uniqueListInsert(List list1, List list2)
6. uniqueMacTest(List macs, String attempt)