Java Collection First getFirst(Collection l)

Here you can find the source of getFirst(Collection l)

Description

get First

License

Open Source License

Declaration

public static <T> T getFirst(Collection<T> l) 

Method Source Code

//package com.java2s;
/*//from w  w  w. j  a  v  a 2  s .co  m
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 2011 OpenConcerto, by ILM Informatique. All rights reserved.
 * 
 * The contents of this file are subject to the terms of the GNU General Public License Version 3
 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a
 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each file.
 */

import java.util.Collection;

import java.util.List;

public class Main {
    public static <T> T getFirst(Collection<T> l) {
        return l.size() > 0 ? l.iterator().next() : null;
    }

    /**
     * Return the first item of <code>l</code> if it isn't empty, otherwise <code>null</code>.
     * 
     * @param <T> type of list.
     * @param l the list.
     * @return the first item of <code>l</code> or <code>null</code>.
     */
    public static <T> T getFirst(List<T> l) {
        return getNoExn(l, 0);
    }

    /**
     * Return the item no <code>index</code> of <code>l</code> if it exists, otherwise
     * <code>null</code>.
     * 
     * @param <T> type of list.
     * @param l the list.
     * @param index the wanted index.
     * @return the corresponding item of <code>l</code> or <code>null</code>.
     */
    public static <T> T getNoExn(List<T> l, int index) {
        return index >= 0 && index < l.size() ? l.get(index) : null;
    }
}

Related

  1. getFirst(Collection collection)
  2. getFirst(Collection collection)
  3. getFirst(Collection collection)
  4. getFirst(Collection collection)
  5. getFirst(Collection collection)
  6. getFirst(Collection set)
  7. getFirst(Collection set, boolean remove)
  8. getFirst(Collection ts)
  9. getFirst(final Collection collection)