Here you can find the source of equalsNull(Collection collection)
@SuppressWarnings("rawtypes") public static Boolean equalsNull(Collection collection)
//package com.java2s; //License from project: Open Source License import java.util.Collection; public class Main { public static Boolean equalsNull(Object object) { return object == null; }/* www . j av a 2 s . c om*/ @SuppressWarnings("rawtypes") public static Boolean equalsNull(Collection collection) { return collection == null; } }