javax.faces.validator

Class LengthValidator

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

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