Java List Single Value singletonListIfNotNullOrEmptyListIfNull(T element)

Description

singleton List If Not Null Or Empty List If Null

License

Open Source License

Declaration

@SuppressWarnings("unchecked")
    public static <T> List<T> singletonListIfNotNullOrEmptyListIfNull(T element) 

Method Source Code

//package com.java2s;
/*/*from   w w  w. j av a 2s . c  om*/
 * Copyright (c) 2013, SRI International
 * All rights reserved.
 * Licensed under the The BSD 3-Clause License;
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 * 
 * http://opensource.org/licenses/BSD-3-Clause
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of the aic-util nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

import java.util.Arrays;

import java.util.LinkedList;
import java.util.List;

public class Main {
    @SuppressWarnings("unchecked")
    public static <T> List<T> singletonListIfNotNullOrEmptyListIfNull(T element) {
        if (element == null) {
            return new LinkedList<T>();
        } else {
            return list(element);
        }
    }

    /**
     * Construct a list of the given type populated with the provided elements.
     * 
     * @param elements
     *            the elements to construct the List from.
     * @return the received arguments in a linked list.
     * @param <T>
     *            the type of the elements in the list.
     */
    @SafeVarargs
    public static <T> List<T> list(T... elements) {
        return new LinkedList<T>(Arrays.asList(elements));
    }
}

Related

1. singleElementList(T element)
2. singleItemAsList(T item)
3. singleQuoatanizeStringList(List entries)
4. singletonList(final T source)
5. singletonList(T element)
6. singleValue(Class type, List values)
7. singleValue(List l)
8. singleValue(List values)