LengthValidator (Jakarta EE 8 Specification APIs)

java.lang.Object
- javax.faces.validator.LengthValidator

All Implemented Interfaces:

EventListener, PartialStateHolder, StateHolder, Validator
```
public class LengthValidator
extends Object
implements Validator, PartialStateHolder
```
LengthValidator is a Validator that checks the number of characters in the String representation of the value of the associated component. The following algorithm is implemented:
- Convert the passed value to a String, if necessary, by calling its toString() method.
- If a maximum property has been configured on this Validator, check the length of the converted String against this limit. If the String length is larger than the specified maximum, throw a ValidatorException containing a a MAXIMUM_MESSAGE_ID message.
- If a minimum property has been configured on this Validator, check the length of the converted String against this limit. If the String length is less than the specified minimum, throw a ValidatorException containing a a MINIMUM_MESSAGE_ID message.
For all of the above cases that cause a ValidatorException to be thrown, if there are parameters to the message that match up with validator parameters, the values of these parameters must be converted using the Converter registered in the application under the converter id javax.faces.Number. This allows the values to be localized according to the current Locale.

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`MAXIMUM_MESSAGE_ID` The message identifier of the `FacesMessage` to be created if the maximum length check fails.
`static String`	`MINIMUM_MESSAGE_ID` The message identifier of the `FacesMessage` to be created if the minimum length check fails.
`static String`	`VALIDATOR_ID` The standard validator id for this validator.

Fields inherited from interface javax.faces.validator.Validator
NOT_IN_RANGE_MESSAGE_ID

Constructor Summary

Constructors
Constructor and Description
`LengthValidator()` Construct a `Validator` with no preconfigured limits.
`LengthValidator(int maximum)` Construct a `Validator` with the specified preconfigured limit.
`LengthValidator(int maximum, int minimum)` Construct a `Validator` with the specified preconfigured limits.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clearInitialState()` Reset the PartialStateHolder to a non-delta tracking state.
`boolean`	`equals(Object otherObj)`
`int`	`getMaximum()` Return the maximum length to be enforced by this `Validator`, or `0` if the maximum has not been set.
`int`	`getMinimum()` Return the minimum length to be enforced by this `Validator`, or `0` if the minimum has not been set.
`int`	`hashCode()`
`boolean`	`initialStateMarked()` Return `true` if delta state changes are being tracked, otherwise `false`
`boolean`	`isTransient()` If true, the Object implementing this interface must not participate in state saving or restoring.
`void`	`markInitialState()` The runtime must ensure that the `PartialStateHolder.markInitialState()` method is called on each instance of this interface in the view at the appropriate time to indicate the component is in its initial state.
`void`	`restoreState(FacesContext context, Object state)` Perform any processing required to restore the state from the entries in the state Object.
`Object`	`saveState(FacesContext context)` Gets the state of the instance as a `Serializable` Object.
`void`	`setMaximum(int maximum)` Set the maximum length to be enforced by this `Validator`.
`void`	`setMinimum(int minimum)` Set the minimum length to be enforced by this `Validator`.
`void`	`setTransient(boolean transientValue)` Denotes whether or not the Object implementing this interface must or must not participate in state saving or restoring.
`void`	`validate(FacesContext context, UIComponent component, Object value)` Perform the correctness checks implemented by this `Validator` against the specified `UIComponent`.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - VALIDATOR_ID
```
public static final String VALIDATOR_ID
```
    The standard validator id for this validator.
    
    See Also:
    
    Constant Field Values
  - MAXIMUM_MESSAGE_ID
```
public static final String MAXIMUM_MESSAGE_ID
```
    The message identifier of the FacesMessage to be created if the maximum length check fails. The message format string for this message may optionally include the following placeholders:
    - {0} replaced by the configured maximum length.
    - {1} replaced by a String whose value is the label of the input component that produced this message.
    See Also:
    
    Constant Field Values
  - MINIMUM_MESSAGE_ID
```
public static final String MINIMUM_MESSAGE_ID
```
    The message identifier of the FacesMessage to be created if the minimum length check fails. The message format string for this message may optionally include the following placeholders:
    - {0} replaced by the configured minimum length.
    - {1} replaced by a String whose value is the label of the input component that produced this message.
    See Also:
    
    Constant Field Values
- Constructor Detail
  - LengthValidator
```
public LengthValidator()
```
    Construct a Validator with no preconfigured limits.
  - LengthValidator
```
public LengthValidator(int maximum)
```
    Construct a Validator with the specified preconfigured limit.
    
    Parameters:
    
    maximum - Maximum value to allow
  - LengthValidator
```
public LengthValidator(int maximum,
                       int minimum)
```
    Construct a Validator with the specified preconfigured limits.
    
    Parameters:
    
    maximum - Maximum value to allow
    
    minimum - Minimum value to allow
- Method Detail
  - getMaximum
```
public int getMaximum()
```
    Return the maximum length to be enforced by this Validator, or 0 if the maximum has not been set.
    
    Returns:
    
    the maximum
  - setMaximum
```
public void setMaximum(int maximum)
```
    Set the maximum length to be enforced by this Validator.
    
    Parameters:
    
    maximum - The new maximum value
  - getMinimum
```
public int getMinimum()
```
    Return the minimum length to be enforced by this Validator, or 0 if the minimum has not been set.
    
    Returns:
    
    the minimum
  - setMinimum
```
public void setMinimum(int minimum)
```
    Set the minimum length to be enforced by this Validator.
    
    Parameters:
    
    minimum - The new minimum value
  - validate
```
public void validate(FacesContext context,
                     UIComponent component,
                     Object value)
              throws ValidatorException
```
    Description copied from interface: Validator
    
    Perform the correctness checks implemented by this Validator against the specified UIComponent. If any violations are found, a ValidatorException will be thrown containing the FacesMessage describing the failure.
    
    For a validator to be fully compliant with Version 2 and later of the specification, it must not fail validation on null or empty values unless it is specifically intended to address null or empty values. An application-wide <context-param> is provided to allow validators designed for Jakarta Server Faces 1.2 to work with Jakarta Server Faces 2 and later. The javax.faces.VALIDATE_EMPTY_FIELDS <context-param> must be set to false to enable this backwards compatibility behavior.
    
    Specified by:
    
    validate in interface Validator
    
    Parameters:
    
    context - FacesContext for the request we are processing
    
    component - UIComponent we are checking for correctness
    
    value - the value to validate
    
    Throws:
    
    NullPointerException - if context or component is null
    
    ValidatorException - if validation fails
  - equals
```
public boolean equals(Object otherObj)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - saveState
```
public Object saveState(FacesContext context)
```
    Description copied from interface: StateHolder
    Gets the state of the instance as a Serializable Object.
    
    If the class that implements this interface has references to instances that implement StateHolder (such as a UIComponent with event handlers, validators, etc.) this method must call the StateHolder.saveState(javax.faces.context.FacesContext) method on all those instances as well. This method must not save the state of children and facets. That is done via the StateManager
    
    This method must not alter the state of the implementing object. In other words, after executing this code:
```
 Object state = component.saveState(facesContext);
 
```
    component should be the same as before executing it.
    
    The return from this method must be Serializable
    Specified by:
    
    saveState in interface StateHolder
    
    Parameters:
    
    context - the Faces context.
    
    Returns:
    
    the saved state.
  - restoreState
```
public void restoreState(FacesContext context,
                         Object state)
```
    Description copied from interface: StateHolder
    
    Perform any processing required to restore the state from the entries in the state Object.
    
    If the class that implements this interface has references to instances that also implement StateHolder (such as a UIComponent with event handlers, validators, etc.) this method must call the StateHolder.restoreState(javax.faces.context.FacesContext, java.lang.Object) method on all those instances as well.
    
    If the state argument is null, take no action and return.
    
    Specified by:
    
    restoreState in interface StateHolder
    
    Parameters:
    
    context - the Faces context.
    
    state - the state.
  - isTransient
```
public boolean isTransient()
```
    Description copied from interface: StateHolder
    
    If true, the Object implementing this interface must not participate in state saving or restoring.
    
    Specified by:
    
    isTransient in interface StateHolder
    
    Returns:
    
    true if transient, false otherwise.
  - setTransient
```
public void setTransient(boolean transientValue)
```
    Description copied from interface: StateHolder
    
    Denotes whether or not the Object implementing this interface must or must not participate in state saving or restoring.
    
    Specified by:
    
    setTransient in interface StateHolder
    
    Parameters:
    
    transientValue - boolean pass true if this Object will not participate in state saving or restoring, otherwise pass false.
  - markInitialState
```
public void markInitialState()
```
    Description copied from interface: PartialStateHolder
    
    The runtime must ensure that the PartialStateHolder.markInitialState() method is called on each instance of this interface in the view at the appropriate time to indicate the component is in its initial state. The implementor of the interface must ensure that PartialStateHolder.initialStateMarked() returns true from the time markInitialState() is called until PartialStateHolder.clearInitialState() is called, after which time initialStateMarked() must return false. Also, during the time that the instance returns true from initialStateMarked(), the implementation must return only the state that has changed in its implementation of StateHolder.saveState(javax.faces.context.FacesContext).
    
    Specified by:
    
    markInitialState in interface PartialStateHolder
  - initialStateMarked
```
public boolean initialStateMarked()
```
    Description copied from interface: PartialStateHolder
    
    Return true if delta state changes are being tracked, otherwise false
    
    Specified by:
    
    initialStateMarked in interface PartialStateHolder
    
    Returns:
    
    true if the initial state is marked, false otherwise.
  - clearInitialState
```
public void clearInitialState()
```
    Description copied from interface: PartialStateHolder
    
    Reset the PartialStateHolder to a non-delta tracking state.
    
    Specified by:
    
    clearInitialState in interface PartialStateHolder

Class LengthValidator

Field Summary

Fields inherited from interface javax.faces.validator.Validator

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

VALIDATOR_ID

MAXIMUM_MESSAGE_ID

MINIMUM_MESSAGE_ID

Constructor Detail

LengthValidator

LengthValidator

LengthValidator

Method Detail

getMaximum

setMaximum

getMinimum

setMinimum

validate

equals

hashCode

saveState

restoreState

isTransient

setTransient

markInitialState

initialStateMarked

clearInitialState