org.apache.commons.validator

Class Validator

Implemented Interfaces:
Serializable

public class Validator
extends java.lang.Object
implements Serializable

Validations are processed by the validate method. An instance of ValidatorResources is used to define the validators (validation methods) and the validation rules for a JavaBean.
Version:
$Revision: 478345 $ $Date: 2006-11-22 22:25:19 +0000 (Wed, 22 Nov 2006) $

Field Summary

static String
BEAN_PARAM
Resources key the JavaBean is stored to perform validation on.
static String
FIELD_PARAM
Resources key the Field is stored under.
static String
FORM_PARAM
Resources key the Form is stored under.
static String
LOCALE_PARAM
Resources key the Locale is stored.
static String
VALIDATOR_ACTION_PARAM
Resources key the ValidatorAction is stored under.
static String
VALIDATOR_PARAM
Resources key the Validator is stored under.
static String
VALIDATOR_RESULTS_PARAM
Resources key the ValidatorResults is stored under.
protected ClassLoader
classLoader
The class loader to use for instantiating application objects.
protected String
fieldName
The name of the field on the form to validate
protected String
formName
The name of the form to validate
protected boolean
onlyReturnErrors
Set this to true to not return Fields that pass validation.
protected int
page
The current page number to validate.
protected Map
parameters
Maps validation method parameter class names to the objects to be passed into the method.
protected ValidatorResources
resources
The Validator Resources.
protected boolean
useContextClassLoader
Whether or not to use the Context ClassLoader when loading classes for instantiating new objects.

Constructor Summary

Validator(ValidatorResources resources)
Construct a Validator that will use the ValidatorResources passed in to retrieve pluggable validators the different sets of validation rules.
Validator(ValidatorResources resources, String formName)
Construct a Validator that will use the ValidatorResources passed in to retrieve pluggable validators the different sets of validation rules.
Validator(ValidatorResources resources, String formName, String fieldName)
Construct a Validator that will use the ValidatorResources passed in to retrieve pluggable validators the different sets of validation rules.

Method Summary

void
clear()
Clears the form name, resources that were added, and the page that was set (if any).
ClassLoader
getClassLoader()
Return the class loader to be used for instantiating application objects when required.
String
getFormName()
Gets the form name which is the key to a set of validation rules.
boolean
getOnlyReturnErrors()
Returns true if the Validator is only returning Fields that fail validation.
int
getPage()
Gets the page.
Object
getParameterValue(String parameterClassName)
Returns the value of the specified parameter that will be used during the processing of validations.
boolean
getUseContextClassLoader()
Return the boolean as to whether the context classloader should be used.
void
setClassLoader(ClassLoader classLoader)
Set the class loader to be used for instantiating application objects when required.
void
setFieldName(String fieldName)
Sets the name of the field to validate in a form (optional)
void
setFormName(String formName)
Sets the form name which is the key to a set of validation rules.
void
setOnlyReturnErrors(boolean onlyReturnErrors)
Configures which Fields the Validator returns from the validate() method.
void
setPage(int page)
Sets the page.
void
setParameter(String parameterClassName, Object parameterValue)
Set a parameter of a pluggable validation method.
void
setUseContextClassLoader(boolean use)
Determine whether to use the Context ClassLoader (the one found by calling Thread.currentThread().getContextClassLoader()) to resolve/load classes that are defined in various rules.
ValidatorResults
validate()
Performs validations based on the configured resources.

Field Details

BEAN_PARAM

public static final String BEAN_PARAM
Resources key the JavaBean is stored to perform validation on.

FIELD_PARAM

public static final String FIELD_PARAM
Resources key the Field is stored under. This will be automatically passed into a validation method with the current Field if it is specified in the method signature.

FORM_PARAM

public static final String FORM_PARAM
Resources key the Form is stored under. This will be automatically passed into a validation method with the current Form if it is specified in the method signature.

LOCALE_PARAM

public static final String LOCALE_PARAM
Resources key the Locale is stored. This will be used to retrieve the appropriate FormSet and Form to be processed.

VALIDATOR_ACTION_PARAM

public static final String VALIDATOR_ACTION_PARAM
Resources key the ValidatorAction is stored under. This will be automatically passed into a validation method with the current ValidatorAction if it is specified in the method signature.

VALIDATOR_PARAM

public static final String VALIDATOR_PARAM
Resources key the Validator is stored under. This will be automatically passed into a validation method with the current Validator if it is specified in the method signature.

VALIDATOR_RESULTS_PARAM

public static final String VALIDATOR_RESULTS_PARAM
Resources key the ValidatorResults is stored under. This will be automatically passed into a validation method with the current ValidatorResults if it is specified in the method signature.

classLoader

protected ClassLoader classLoader
The class loader to use for instantiating application objects. If not specified, the context class loader, or the class loader used to load Digester itself, is used, based on the value of the useContextClassLoader variable.

fieldName

protected String fieldName
The name of the field on the form to validate
Since:
1.2.0

formName

protected String formName
The name of the form to validate

onlyReturnErrors

protected boolean onlyReturnErrors
Set this to true to not return Fields that pass validation. Only return failures.

page

protected int page
The current page number to validate.

parameters

protected Map parameters
Maps validation method parameter class names to the objects to be passed into the method.

resources

protected ValidatorResources resources
The Validator Resources.

useContextClassLoader

protected boolean useContextClassLoader
Whether or not to use the Context ClassLoader when loading classes for instantiating new objects. Default is false.

Constructor Details

Validator

public Validator(ValidatorResources resources)
Construct a Validator that will use the ValidatorResources passed in to retrieve pluggable validators the different sets of validation rules.
Parameters:
resources - ValidatorResources to use during validation.

Validator

public Validator(ValidatorResources resources,
                 String formName)
Construct a Validator that will use the ValidatorResources passed in to retrieve pluggable validators the different sets of validation rules.
Parameters:
resources - ValidatorResources to use during validation.
formName - Key used for retrieving the set of validation rules.

Validator

public Validator(ValidatorResources resources,
                 String formName,
                 String fieldName)
Construct a Validator that will use the ValidatorResources passed in to retrieve pluggable validators the different sets of validation rules.
Parameters:
resources - ValidatorResources to use during validation.
formName - Key used for retrieving the set of validation rules.
fieldName - Key used for retrieving the set of validation rules for a field
Since:
1.2.0

Method Details

clear

public void clear()
Clears the form name, resources that were added, and the page that was set (if any). This can be called to reinitialize the Validator instance so it can be reused. The form name (key to set of validation rules) and any resources needed, like the JavaBean being validated, will need to set and/or added to this instance again. The ValidatorResources will not be removed since it can be used again and is thread safe.

getClassLoader

public ClassLoader getClassLoader()
Return the class loader to be used for instantiating application objects when required. This is determined based upon the following rules:
  • The class loader set by setClassLoader(), if any
  • The thread context class loader, if it exists and the useContextClassLoader property is set to true
  • The class loader used to load the Digester class itself.
Returns:
the class loader.

getFormName

public String getFormName()
Gets the form name which is the key to a set of validation rules.
Returns:
the name of the form.

getOnlyReturnErrors

public boolean getOnlyReturnErrors()
Returns true if the Validator is only returning Fields that fail validation.
Returns:
whether only failed fields are returned.

getPage

public int getPage()
Gets the page. This in conjunction with the page property of a Field can control the processing of fields. If the field's page is less than or equal to this page value, it will be processed.
Returns:
the page number.

getParameterValue

public Object getParameterValue(String parameterClassName)
Returns the value of the specified parameter that will be used during the processing of validations.
Parameters:
parameterClassName - The full class name of the parameter of the validation method that corresponds to the value/instance passed in with it.
Returns:
value of the specified parameter.

getUseContextClassLoader

public boolean getUseContextClassLoader()
Return the boolean as to whether the context classloader should be used.
Returns:
whether the context classloader should be used.

setClassLoader

public void setClassLoader(ClassLoader classLoader)
Set the class loader to be used for instantiating application objects when required.
Parameters:
classLoader - The new class loader to use, or null to revert to the standard rules

setFieldName

public void setFieldName(String fieldName)
Sets the name of the field to validate in a form (optional)
Parameters:
fieldName - The name of the field in a form set
Since:
1.2.0

setFormName

public void setFormName(String formName)
Sets the form name which is the key to a set of validation rules.
Parameters:
formName - the name of the form.

setOnlyReturnErrors

public void setOnlyReturnErrors(boolean onlyReturnErrors)
Configures which Fields the Validator returns from the validate() method. Set this to true to only return Fields that failed validation. By default, validate() returns all fields.
Parameters:
onlyReturnErrors - whether only failed fields are returned.

setPage

public void setPage(int page)
Sets the page. This in conjunction with the page property of a Field can control the processing of fields. If the field's page is less than or equal to this page value, it will be processed.
Parameters:
page - the page number.

setParameter

public void setParameter(String parameterClassName,
                         Object parameterValue)
Set a parameter of a pluggable validation method.
Parameters:
parameterClassName - The full class name of the parameter of the validation method that corresponds to the value/instance passed in with it.
parameterValue - The instance that will be passed into the validation method.

setUseContextClassLoader

public void setUseContextClassLoader(boolean use)
Determine whether to use the Context ClassLoader (the one found by calling Thread.currentThread().getContextClassLoader()) to resolve/load classes that are defined in various rules. If not using Context ClassLoader, then the class-loading defaults to using the calling-class' ClassLoader.
Parameters:
use - determines whether to use Context ClassLoader.

validate

public ValidatorResults validate()
            throws ValidatorException
Performs validations based on the configured resources.
Returns:
The Map returned uses the property of the Field for the key and the value is the number of error the field had.
Throws:
ValidatorException - If an error occurs during validation

Copyright (c) 2001-2004 Apache Software Foundation