Java List First Item first(List list)

Description

first

License

Apache License

Parameter

Parameter	Description
list	a parameter

Declaration

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

Method Source Code

//package com.java2s;
/*/*from   ww  w .j  a v a 2 s  .  c  om*/
 * Copyright 2014 the original author or authors.
 *
 * 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.
 *   
 * Create Date : 2014-9-29
 */

import java.util.Collection;

import java.util.List;

public class Main {

    public static <T> T first(List<T> list) {
        return first(list, null);
    }

    public static <T> T first(List<T> list, T defaultValue) {
        return get(list, 0, null);
    }

    public static <T> T get(List<T> list, int index) {
        return get(list, index, null);
    }

    public static <T> T get(List<T> list, int index, T defaultValue) {
        int max = size(list) - 1;
        if (max == -1 || index < 0 || index > max)
            return defaultValue;

        return list.get(index);
    }

    public static int size(Collection<?> collection) {
        return collection != null ? collection.size() : 0;
    }
}

Related

1. first(List list)
2. first(List list)
3. first(List list)
4. first(List list)
5. first(List list)
6. first(List list)
7. first(List list)
8. first_nItems(int n, Collection fromList)
9. firstBoolean(List list)