Java tutorial
//package com.java2s; import java.util.Collection; public class Main { public static boolean isValid(String src) { return !(src == null || "".equals(src.trim())); } public static boolean isValid(Object obj) { return !(null == obj); } @SuppressWarnings("rawtypes") public static boolean isValid(Collection col) { return !(col == null || col.isEmpty()); } public static boolean isValid(Object[] arr) { return !(arr == null || arr.length == 0); } }