public static boolean isBlank(final CharSequence cs) {
		if (cs == null || cs.length() == 0) {
			return true;
		}
		int strLen = cs.length();
		for (int i = 0; i < strLen; i++) {
			if (!Character.isWhitespace(cs.charAt(i))) {
				return false;
			}
		}
		return true;
	}
<p>
Checks if a CharSequence 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 cs the CharSequence to check, may be null
@return {@code true} if the CharSequence is null, empty or whitespace
spring-cloud-alibaba-starters/spring-cloud-alibaba-commons/src/main/java/com/alibaba/cloud/commons/lang/StringUtils.java