What would be the regular expression to check a string value is "Not null and not empty" in java?
i tried like this "/^$|\s+/", but seems not working.
3 Answers
Considering this: your string can not contain "null" as string:
String.valueOf(input).matches("^null|$");
Otherwise check input != null and remove null| from the regex.
1 Comment
Tim Pietzcker
Anchors are unnecessary with the
.matches() method.".*\\S+.*"
This means there is at least one non-whitespace character in the string. But you should watch out—if you call the string as an implicit parameter and it's null, you'll see a NullPointerException. Thus, it's probably better to check for null using conditionals.
Comments
You cannot check for not-null using a regular expression, because that regex is run against the String.
To check the String isn't empty you can just use !myString.isEmpty()
so if(myString != null && !myString.isEmpty())
Of course, in Groovy it would just be if(myString) ;)
" "to be "empty"?/^$|\s+/equates to 'empty string OR any string containing at least one whitespace character'