Type Parameters:

V - type of the value to validate.

All Superinterfaces:

Composable<Validator<?>>, Iterable<Validator<?>>

All Known Implementing Classes:

AbstractComposedValidator, AbstractValidator, AbstractValidatorRange, AbstractValueValidator, ComposedValidator, ProjectionValidator, ValidatorCharSequnceSize, ValidatorCollectionElements, ValidatorCollectionSize, ValidatorCompare, ValidatorEmail, ValidatorEmailSpec, ValidatorHost, ValidatorHostName, ValidatorInstantAfter, ValidatorInstantBefore, ValidatorInstantFuture, ValidatorInstantPast, ValidatorIpAddress, ValidatorIpV4Address, ValidatorIpV6Address, ValidatorLocalDateAfter, ValidatorLocalDateBefore, ValidatorLocalDateFuture, ValidatorLocalDatePast, ValidatorLocalDateTimeAfter, ValidatorLocalDateTimeBefore, ValidatorLocalDateTimeFuture, ValidatorLocalDateTimePast, ValidatorLocalTimeAfter, ValidatorLocalTimeBefore, ValidatorLocalTimeFuture, ValidatorLocalTimePast, ValidatorMandatory, ValidatorMapKeys, ValidatorMapSize, ValidatorMapValues, ValidatorOffsetDateTimeAfter, ValidatorOffsetDateTimeBefore, ValidatorOffsetDateTimeFuture, ValidatorOffsetDateTimePast, ValidatorOffsetTimeAfter, ValidatorOffsetTimeBefore, ValidatorOffsetTimeFuture, ValidatorOffsetTimePast, ValidatorPasswordConfirmation, ValidatorPattern, ValidatorPhoneNumber, ValidatorRange, ValidatorTemporalAfter, ValidatorTemporalBefore, ValidatorTemporalFuture, ValidatorTemporalPast, ValidatorZonedDateTimeAfter, ValidatorZonedDateTimeBefore, ValidatorZonedDateTimeFuture, ValidatorZonedDateTimePast
```
public interface Validator<V>
extends Composable<Validator<?>>
```
A Validator allows to validate according values.
There can be arbitrary implementations of this interface. A regular implementation shall be stateless and therefore thread-safe. All parameterization shall therefore happen on initialization - ideally at construction.
NOTE:
This API intentionally does NOT make use of exceptions as they are more expensive to produce and shall only occur in exceptional situations, while a validation failure is a regular use-case. Further, a validation shall validate entire objects to the end collecting all failures so the end-user can see and fix all problems at once.
ATTENTION:
The null values is typically only handled by mandatory validator. Other validators will treat null as a valid value. This design gives the best flexibility as it allows to define specific constraints also for optional values. However, you need to be aware this fact to avoid mistakes. So e.g. adding a validator requiring that the minimum size/length of a value needs to be e.g. 2 will still accept null as valid. So in such case you most probably want to combine it with the mandatory validator.

Since:

1.0.0

Field Summary

Fields
Modifier and Type Field Description

static String ID_MANDATORY

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`default <T> Validator<T>`	`append(Validator<?> validator)`
`default <T> Validator<T>`	`append(Validator<?>... validators)`
`default boolean`	`containsId(String id)`
`String`	`getId()`
`default Object`	`getMax()`
`default Object`	`getMin()`
`default boolean`	`isMandatory()`
`static boolean`	`isValidating(Validator<?> validator)`
`static <T> Validator<T>`	`none()`
`default ValidationResult`	`validate(V value)`	This method validates the given `value`.
`ValidationResult`	`validate(V value, Object valueSource)`	This method validates the given `value`.

Methods inherited from interface io.github.mmm.base.lang.Composable
getChild, getChildCount, iterator

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Field Detail
  - ID_MANDATORY
```
static final String ID_MANDATORY
```
    See Also:
    
    isMandatory(), getId(), Constant Field Values
- Method Detail
  - validate
```
default ValidationResult validate(V value)
```
    This method validates the given value.
    
    Parameters:
    
    value - is the value to validate.
    
    Returns:
    
    the ValidationResult or null if the given value is valid according to this Validator.
  - validate
```
ValidationResult validate(V value,
                          Object valueSource)
```
    This method validates the given value.
    
    Parameters:
    
    value - is the value to validate.
    
    valueSource - is the source describing the origin of the given value. The source needs to have a reasonable string-representation as this may be displayed to the end-user to locate the source of the failure. In most cases it is suitable to directly pass a String.
    
    Returns:
    
    the ValidationResult.
  - getId
```
String getId()
```
    Returns:
    
    the identifier of this Validator.
    
    See Also:
    
    ValidationResult.getCode()
  - isMandatory
```
default boolean isMandatory()
```
    Returns:
    
    true if this is a validator for mandatory fields (that will not accept null or empty values), false otherwise.
  - containsId
```
default boolean containsId(String id)
```
    Parameters:
    
    id - the ID of the Validator to check for.
    
    Returns:
    
    true if this Validator itself has the given ID or recursively contains such Validator, false otherwise.
  - getMin
```
default Object getMin()
```
    Returns:
    
    the minimum allowed value. Typically of type <V> but this can not be guaranteed.
  - getMax
```
default Object getMax()
```
    Returns:
    
    the maximum allowed value. Typically of type <V> but this can not be guaranteed.
  - append
```
default <T> Validator<T> append(Validator<?> validator)
```
    Type Parameters:
    
    T - type of the value to validate.
    
    Parameters:
    
    validator - the Validator to append.
    
    Returns:
    
    a new Validator instance composing this Validator with the given Validator.
  - append
```
default <T> Validator<T> append(Validator<?>... validators)
```
    Type Parameters:
    
    T - type of the value to validate.
    
    Parameters:
    
    validators - the Validators to append.
    
    Returns:
    
    a new Validator instance composing this Validator with the given Validators.
  - none
```
static <T> Validator<T> none()
```
    Type Parameters:
    
    T - type of the value to validate.
    
    Returns:
    
    an instance of Validator that always return ValidationResultValid (accepts any value as valid input).
  - isValidating
```
static boolean isValidating(Validator<?> validator)
```
    Parameters:
    
    validator - the Validator to check. May be null.
    
    Returns:
    
    true if the given Validator is neither null nor none, false otherwise.

Interface Validator<V>

Field Summary

Method Summary

Methods inherited from interface io.github.mmm.base.lang.Composable

Methods inherited from interface java.lang.Iterable

Field Detail

ID_MANDATORY

Method Detail

validate

validate

getId

isMandatory

containsId

getMin

getMax

append

append

none

isValidating