Java ArrayList Create asArrayList(Collection collection)

Description

If input collection is ArrayList then return it.

License

Apache License

Parameter

Parameter	Description
collection	the collection.

Return

the array list of elements of collection.

Declaration

public static <T> List<T> asArrayList(Collection<T> collection) 

Method Source Code

//package com.java2s;
/*//w ww .j  av  a  2  s .  co m
 * Copyright 2008-2010 Ruslan Khmelyuk.
 *
 * 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.*;

public class Main {
    /**
     * If input collection is {@code ArrayList} then return it.
     * Otherwise creates new {@code ArrayList} with elements from {@code collection} and return it.
     *
     * @param collection the collection.
     * @return the array list of elements of collection.
     */
    public static <T> List<T> asArrayList(Collection<T> collection) {
        if (collection instanceof ArrayList) {
            return (List<T>) collection;
        }
        return new ArrayList<T>(collection);
    }
}

Related

1. asArrayList(Collection list)
2. createArrayList()
3. createArrayList()
4. createArrayList(Collection arg)
5. createArrayList(E... array)