Checking for Null or Empty or White Space Only String in Java

/**
 * Demonstrate checking for String that is not null, not empty, and not white
 * space only using standard Java classes.
 *
 * @param string String to be checked for not null, not empty, and not white
 *    space only.
 * @return {@code true} if provided String is not null, is not empty, and
 *    has at least one character that is not considered white space.
 */
public static boolean isNotNullNotEmptyNotWhiteSpaceOnlyByJava(
   final String string)
{
   return string != null && !string.isEmpty() && !string.trim().isEmpty();
}


Refer:
http://marxsoftware.blogspot.in/2011/09/checking-for-null-or-empty-or-white.html