How to set a character limit in Java

Question

If I want to make a simple password checker in java and lets say I have a string and I want to count the characters in it, then make sure that it is above six, what would I do?

Answer 1

Your can call length() method on String object. It returns length of that string.

if (str.length() <= 6) //or < 7
    //do something
else
    //do something

You can not explicitly set character limit in String object.

Answer 2

Well, just use length() function that's built-in for String

String string = "Hello World!";
if(string.length() > 6) {
    //TODO
}

Answer 3

The only way I know to enforce the length of a password upon input is as follows:

• the regex finds the first occurrence of any password over 5 characters that does not contain white space.

Scanner s = new Scanner(System.in);
String pwd = "";
for (int i = 0; i < 10; i++) {
    pwd = s.findInLine("[^\\s]{6,}");
    if (pwd != null) {
        break;
    }
    String attempt = s.nextLine();
    System.out.println(attempt + " -- Invalid password");
}
System.out.println("Valid password = " + pwd);

Note that this solution tries to meet your requirement but is not necessarily better than those answers that suggested using String.length()