Java List Remove Null Value removeNullElement(List source)

Description

Removes all of the 'null' elements in a list, recursively.

License

Apache License

Parameter

Parameter	Description
source	a parameter

Return

source - java.util.List

Declaration

public static List removeNullElement(List source) 

Method Source Code

//package com.java2s;
//License from project: Apache License 

import java.util.List;

public class Main {
    /**/*  w  ww.  ja  v a2 s .c  o  m*/
     * Removes all of the 'null' elements in a list, recursively.
     * 
     * @param source
     * @return source - java.util.List
     */
    public static List removeNullElement(List source) {
        if (!containsNullElement(source))
            return source;
        while (source.contains(null)) {
            source.remove(null);
        }
        return source;

    }

    /**
     * Checks whether 'list' has any null element in it. 1- if list itself is
     * null, return false 2- if list is empty, return false 3- if list contains
     * any null element, return true Note: Return true on first instance of
     * finding null element
     * 
     * @param source
     * @return boolean
     */
    public static boolean containsNullElement(List source) {
        if (source == null)
            return false;
        if (source.isEmpty())
            return false;
        if (source.contains(null))
            return true;
        return false;
    }
}

Related

1. removeNull(Collection