See summary steps to CREATE a custom validator :

1. Implements IValidator.

import org.apache.wicket.validation.IValidator;

 public class Strong PasswordValidator implements IValidator<String>{

...

}

2. Override validate(IValidatable validatable).

public class StrongPasswordValidator implements IValidator<String>{

...

@Override

public void validate(IValidatable<String> validatable) {

//get input from ATTACHED COMPONENT

FINAL String field = validatable.getValue();

}

}

3. Attached custom validator to form component.

public class CustomValidatorPage extends WebPage {

public CustomValidatorPage(final PageParameters parameters) {

final PasswordTextField password = new PasswordTextField("password",Model.of(""));

//attached custom validator to password field

password.add(new StrongPasswordValidator());

//...

}

 }

See summary steps to create a custom validator :

1. Implements IValidator.

import org.apache.wicket.validation.IValidator;

 public class Strong PasswordValidator implements IValidator<String>{

...

}

2. Override validate(IValidatable validatable).

public class StrongPasswordValidator implements IValidator<String>{

...

@Override

public void validate(IValidatable<String> validatable) {

//get input from attached component

final String field = validatable.getValue();

}

}

3. Attached custom validator to form component.

public class CustomValidatorPage extends WebPage {

public CustomValidatorPage(final PageParameters parameters) {

final PasswordTextField password = new PasswordTextField("password",Model.of(""));

//attached custom validator to password field

password.add(new StrongPasswordValidator());

//...

}

 }