Package com.vaadin.flow.data.validator

Class AbstractValidator<T>

java.lang.Object
com.vaadin.flow.data.validator.AbstractValidator<T>
Type Parameters:
T - The value type
All Implemented Interfaces:
Validator<T>, Serializable, BiFunction<T,ValueContext,ValidationResult>
Direct Known Subclasses:
RangeValidator, RegexpValidator, StringLengthValidator
public abstract class AbstractValidator<T> extends Object implements Validator<T>
An abstract base class for typed validators.
Since:
1.0.
Author:
Vaadin Ltd
See Also:

  • Constructor Details

    • AbstractValidator

      protected AbstractValidator(String errorMessage)
      Constructs a validator with the given error message. The substring "{0}" is replaced by the value that failed validation.
      Parameters:
      errorMessage - the message to be included in a failed result, not null

  • Method Details

    • getMessage

      protected String getMessage(T value)
      Returns the error message for the given value.
      Parameters:
      value - an invalid value
      Returns:
      the formatted error message

    • toResult

      protected ValidationResult toResult(T value, boolean isValid)
      A helper method for creating a Result from a value and a validity flag. If the flag is true, returns Result.ok, otherwise yields Result.error bearing the error message returned by getMessage(Object).

      For instance, the following apply method only accepts even numbers: 

       @Override
 public Result<T> apply(Integer value) {
     return toResult(value, value % 2 == 0);
 }
      Parameters:
      value - the validated value
      isValid - whether the value is valid or not
      Returns:
      the validation result