Write code toChecks if a String is whitespace, empty ("") or null.
//package com.book2s; public class Main { public static void main(String[] argv) { String str = "book2s.com"; System.out.println(isBlank(str)); }/* ww w. j a v a 2 s. c o m*/ /** * <p> * Checks if a String is whitespace, empty ("") or null. * </p> * * <pre> * StringUtils.isBlank(null) = true * StringUtils.isBlank("") = true * StringUtils.isBlank(" ") = true * StringUtils.isBlank("bob") = false * StringUtils.isBlank(" bob ") = false * </pre> * * @param str * the String to check, may be null * @return <code>true</code> if the String is null, empty or whitespace * @since 2.0 */ public static boolean isBlank(String str) { int strLen; if (str == null || (strLen = str.length()) == 0) { return true; } for (int i = 0; i < strLen; i++) { if (!Character.isWhitespace(str.charAt(i))) { return false; } } return true; } }