I have a task to check if a new string (login) complies some rules These are rules:
1. It has to be 1-20 symbols length
2. It may consist of digits, letters (a-z,A-Z), dots and "-"
3. The first symbol has to be a letter (a-z,A-Z)
4. It has to end with a letter or a digit
So i thought of using java.util.regex.Pattern, and I ran in some problems. Thats what i have:
String login = "a.bc-.52";
Pattern p1 = Pattern.compile("([a-zA-Z]{1}[a-zA-Z\\d.-]{0,18}[a-zA-Z\\d])");
Matcher m1 = p1.matcher(login);
boolean b = m1.matches();
I'm having trouble to check if string ends with a letter or a diggit. I think i could split the string and check its parts with different patterns, but something tells me, that it can be done easier.
I'm sorry if it is a dumb questions or i've made mistakes. Perhaps there is easier way, please tell me. Thank you
^[a-zA-Z]{1}[a-zA-Z\\d.-]{0,18}[a-zA-Z\\d]$
^
<- ensures that the string begins with a letter
$
<- ensures that the string ends with a letter of digit
What you are looking for is the dollar sign. Simple as that:
t$ --> ends in t
The opposite is ^
^a - starts with a
So in your case just add the dollar sign at the end.
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