Here you can find the source of nvl(String str)
public static String nvl(String str)
//package com.java2s; //License from project: Open Source License public class Main { public static String nvl(String str) { return isNull(str) ? "" : str; }/*from w w w.j av a2s. c om*/ public static boolean isNull(String str) { return str == null; } }