Module jakarta.faces

Package jakarta.faces.validator

Class MethodExpressionValidator

java.lang.Object

jakarta.faces.validator.MethodExpressionValidator

All Implemented Interfaces:

StateHolder, Validator, EventListener

public class MethodExpressionValidator
extends Object
implements Validator, StateHolder

MethodExpressionValidator is a Validator that wraps a MethodExpression, and it performs validation by executing a method on an object identified by the MethodExpression.

Constructor Summary

Constructors

Constructor	Description
MethodExpressionValidator()
MethodExpressionValidator(MethodExpression methodExpression)	Construct a Validator that contains a MethodExpression.

Method Summary

Modifier and Type	Method	Description
boolean	isTransient()	If true, the Object implementing this interface must not participate in state saving or restoring.
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	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, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

MethodExpressionValidator

public MethodExpressionValidator()

MethodExpressionValidator

public MethodExpressionValidator(MethodExpression methodExpression)

Construct a Validator that contains a MethodExpression.

Parameters:

methodExpression - the expression to wrap

Method Details

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 Faces 1.2 to work with Jakarta Faces 2 and later. The jakarta.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

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(jakarta.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(jakarta.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.