Maximum string length

The maxLength() element applies only to String parameters, indicating the maximum number of characters that the user may enter (for example in a text field in the UI). It is ignored if applied to parameters of any other type.

For example:

public class CustomerRepository {
    public Customer newCustomer(
        @Parameter(maxLength=30)
        final String firstName,
        @Parameter(maxLength=50)
        final String lastName) {
        ...
    }
}