org.springframework.validation

Class DataBinder

java.lang.Object

org.springframework.validation.DataBinder

All Implemented Interfaces:

PropertyEditorRegistry, TypeConverter

Direct Known Subclasses:

WebDataBinder

public class DataBinder
extends java.lang.Object
implements PropertyEditorRegistry, TypeConverter

Binder that allows for setting property values onto a target object, including support for validation and binding result analysis. The binding process can be customized through specifying allowed fields, required fields, custom editors, etc.

Note that there are potential security implications in failing to set an array of allowed fields. In the case of HTTP form POST data for example, malicious clients can attempt to subvert an application by supplying values for fields or properties that do not exist on the form. In some cases this could lead to illegal data being set on command objects or their nested objects. For this reason, it is highly recommended to specify the allowedFields property on the DataBinder.

The binding results can be examined via the BindingResult interface, extending the Errors interface: see the getBindingResult() method. Missing fields and property access exceptions will be converted to FieldErrors, collected in the Errors instance, using the following error codes:

• Missing field error: "required"
• Type mismatch error: "typeMismatch"
• Method invocation error: "methodInvocation"

By default, binding errors get resolved through the BindingErrorProcessor strategy, processing for missing fields and property access exceptions: see the setBindingErrorProcessor(org.springframework.validation.BindingErrorProcessor) method. You can override the default strategy if needed, for example to generate different error codes.

Custom validation errors can be added afterwards. You will typically want to resolve such error codes into proper user-visible error messages; this can be achieved through resolving each error via a MessageSource, which is able to resolve an ObjectError/FieldError through its MessageSource.getMessage(org.springframework.context.MessageSourceResolvable, java.util.Locale) method. The list of message codes can be customized through the MessageCodesResolver strategy: see the setMessageCodesResolver(org.springframework.validation.MessageCodesResolver) method. DefaultMessageCodesResolver's javadoc states details on the default resolution rules.

This generic data binder can be used in any kind of environment. It is typically used by Spring web MVC controllers, via the web-specific subclasses ServletRequestDataBinder and PortletRequestDataBinder.

Author:

Rod Johnson, Juergen Hoeller, Rob Harrop

See Also:

setAllowedFields(java.lang.String...), setRequiredFields(java.lang.String...), registerCustomEditor(java.lang.Class<?>, java.beans.PropertyEditor), setMessageCodesResolver(org.springframework.validation.MessageCodesResolver), setBindingErrorProcessor(org.springframework.validation.BindingErrorProcessor), bind(org.springframework.beans.PropertyValues), getBindingResult(), DefaultMessageCodesResolver, DefaultBindingErrorProcessor, MessageSource, ServletRequestDataBinder

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	DataBinder.OptionalUnwrapper Inner class to avoid a hard dependency on Java 8.

Field Summary

Fields

Modifier and Type	Field and Description
private java.lang.String[]	allowedFields
private int	autoGrowCollectionLimit
private boolean	autoGrowNestedPaths
private BindingErrorProcessor	bindingErrorProcessor
private AbstractPropertyBindingResult	bindingResult
private ConversionService	conversionService
static int	DEFAULT_AUTO_GROW_COLLECTION_LIMIT Default limit for array and collection growing: 256
static java.lang.String	DEFAULT_OBJECT_NAME Default object name used for binding: "target"
private java.lang.String[]	disallowedFields
private boolean	ignoreInvalidFields
private boolean	ignoreUnknownFields
private static java.lang.Class<?>	javaUtilOptionalClass
protected static Log	logger We'll create a lot of DataBinder instances: Let's use a static logger.
private java.lang.String	objectName
private java.lang.String[]	requiredFields
private java.lang.Object	target
private SimpleTypeConverter	typeConverter
private java.util.List<Validator>	validators

Constructor Summary

Constructors

Constructor and Description
DataBinder(java.lang.Object target) Create a new DataBinder instance, with default object name.
DataBinder(java.lang.Object target, java.lang.String objectName) Create a new DataBinder instance.

Method Summary

Modifier and Type	Method and Description
void	addCustomFormatter(Formatter<?> formatter) Add a custom formatter, applying it to all fields matching the Formatter-declared type.
void	addCustomFormatter(Formatter<?> formatter, java.lang.Class<?>... fieldTypes) Add a custom formatter, applying it to the specified field types only, if any, or otherwise to all fields matching the Formatter-declared type.
void	addCustomFormatter(Formatter<?> formatter, java.lang.String... fields) Add a custom formatter for the field type specified in Formatter class, applying it to the specified fields only, if any, or otherwise to all fields.
void	addValidators(Validator... validators) Add Validators to apply after each binding step.
protected void	applyPropertyValues(MutablePropertyValues mpvs) Apply given property values to the target object.
private void	assertValidators(Validator... validators)
void	bind(PropertyValues pvs) Bind the given property values to this binder's target.
protected void	checkAllowedFields(MutablePropertyValues mpvs) Check the given property values against the allowed fields, removing values for fields that are not allowed.
protected void	checkRequiredFields(MutablePropertyValues mpvs) Check the given property values against the required fields, generating missing field errors where appropriate.
java.util.Map<?,?>	close() Close this DataBinder, which may result in throwing a BindException if it encountered any errors.
<T> T	convertIfNecessary(java.lang.Object value, java.lang.Class<T> requiredType) Convert the value to the required type (if necessary from a String).
<T> T	convertIfNecessary(java.lang.Object value, java.lang.Class<T> requiredType, java.lang.reflect.Field field) Convert the value to the required type (if necessary from a String).
<T> T	convertIfNecessary(java.lang.Object value, java.lang.Class<T> requiredType, MethodParameter methodParam) Convert the value to the required type (if necessary from a String).
protected void	doBind(MutablePropertyValues mpvs) Actual implementation of the binding process, working with the passed-in MutablePropertyValues instance.
java.beans.PropertyEditor	findCustomEditor(java.lang.Class<?> requiredType, java.lang.String propertyPath) Find a custom property editor for the given type and property.
java.lang.String[]	getAllowedFields() Return the fields that should be allowed for binding.
int	getAutoGrowCollectionLimit() Return the current limit for array and collection auto-growing.
BindingErrorProcessor	getBindingErrorProcessor() Return the strategy for processing binding errors.
BindingResult	getBindingResult() Return the BindingResult instance created by this DataBinder.
ConversionService	getConversionService() Return the associated ConversionService, if any.
java.lang.String[]	getDisallowedFields() Return the fields that should not be allowed for binding.
protected AbstractPropertyBindingResult	getInternalBindingResult() Return the internal BindingResult held by this DataBinder, as AbstractPropertyBindingResult.
java.lang.String	getObjectName() Return the name of the bound object.
protected ConfigurablePropertyAccessor	getPropertyAccessor() Return the underlying PropertyAccessor of this binder's BindingResult.
protected PropertyEditorRegistry	getPropertyEditorRegistry() Return the underlying TypeConverter of this binder's BindingResult.
java.lang.String[]	getRequiredFields() Return the fields that are required for each binding process.
protected SimpleTypeConverter	getSimpleTypeConverter() Return this binder's underlying SimpleTypeConverter.
java.lang.Object	getTarget() Return the wrapped target object.
protected TypeConverter	getTypeConverter() Return the underlying TypeConverter of this binder's BindingResult.
Validator	getValidator() Return the primary Validator to apply after each binding step, if any.
java.util.List<Validator>	getValidators() Return the Validators to apply after data binding.
void	initBeanPropertyAccess() Initialize standard JavaBean property access for this DataBinder.
void	initDirectFieldAccess() Initialize direct field access for this DataBinder, as alternative to the default bean property access.
protected boolean	isAllowed(java.lang.String field) Return if the given field is allowed for binding.
boolean	isAutoGrowNestedPaths() Return whether "auto-growing" of nested paths has been activated.
boolean	isIgnoreInvalidFields() Return whether to ignore invalid fields when binding.
boolean	isIgnoreUnknownFields() Return whether to ignore unknown fields when binding.
void	registerCustomEditor(java.lang.Class<?> requiredType, java.beans.PropertyEditor propertyEditor) Register the given custom property editor for all properties of the given type.
void	registerCustomEditor(java.lang.Class<?> requiredType, java.lang.String field, java.beans.PropertyEditor propertyEditor) Register the given custom property editor for the given type and property, or for all properties of the given type.
void	replaceValidators(Validator... validators) Replace the Validators to apply after each binding step.
void	setAllowedFields(java.lang.String... allowedFields) Register fields that should be allowed for binding.
void	setAutoGrowCollectionLimit(int autoGrowCollectionLimit) Specify the limit for array and collection auto-growing.
void	setAutoGrowNestedPaths(boolean autoGrowNestedPaths) Set whether this binder should attempt to "auto-grow" a nested path that contains a null value.
void	setBindingErrorProcessor(BindingErrorProcessor bindingErrorProcessor) Set the strategy to use for processing binding errors, that is, required field errors and PropertyAccessExceptions.
void	setConversionService(ConversionService conversionService) Specify a Spring 3.0 ConversionService to use for converting property values, as an alternative to JavaBeans PropertyEditors.
void	setDisallowedFields(java.lang.String... disallowedFields) Register fields that should not be allowed for binding.
void	setExtractOldValueForEditor(boolean extractOldValueForEditor) Set whether to extract the old field value when applying a property editor to a new value for a field.
void	setIgnoreInvalidFields(boolean ignoreInvalidFields) Set whether to ignore invalid fields, that is, whether to ignore bind parameters that have corresponding fields in the target object which are not accessible (for example because of null values in the nested path).
void	setIgnoreUnknownFields(boolean ignoreUnknownFields) Set whether to ignore unknown fields, that is, whether to ignore bind parameters that do not have corresponding fields in the target object.
void	setMessageCodesResolver(MessageCodesResolver messageCodesResolver) Set the strategy to use for resolving errors into message codes.
void	setRequiredFields(java.lang.String... requiredFields) Register fields that are required for each binding process.
void	setValidator(Validator validator) Set the Validator to apply after each binding step.
void	validate() Invoke the specified Validators, if any.
void	validate(java.lang.Object... validationHints) Invoke the specified Validators, if any, with the given validation hints.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_OBJECT_NAME

public static final java.lang.String DEFAULT_OBJECT_NAME

Default object name used for binding: "target"

See Also:

Constant Field Values

DEFAULT_AUTO_GROW_COLLECTION_LIMIT

public static final int DEFAULT_AUTO_GROW_COLLECTION_LIMIT

Default limit for array and collection growing: 256

See Also:

Constant Field Values

logger

protected static final Log logger

We'll create a lot of DataBinder instances: Let's use a static logger.

javaUtilOptionalClass

private static java.lang.Class<?> javaUtilOptionalClass

target

private final java.lang.Object target

objectName

private final java.lang.String objectName

bindingResult

private AbstractPropertyBindingResult bindingResult

typeConverter

private SimpleTypeConverter typeConverter

ignoreUnknownFields

private boolean ignoreUnknownFields

ignoreInvalidFields

private boolean ignoreInvalidFields

autoGrowNestedPaths

private boolean autoGrowNestedPaths

autoGrowCollectionLimit

private int autoGrowCollectionLimit

allowedFields

private java.lang.String[] allowedFields

disallowedFields

private java.lang.String[] disallowedFields

requiredFields

private java.lang.String[] requiredFields

bindingErrorProcessor

private BindingErrorProcessor bindingErrorProcessor

validators

private final java.util.List<Validator> validators

conversionService

private ConversionService conversionService

Constructor Detail

DataBinder

public DataBinder(java.lang.Object target)

Create a new DataBinder instance, with default object name.

Parameters:

target - the target object to bind onto (or null if the binder is just used to convert a plain parameter value)

See Also:

DEFAULT_OBJECT_NAME

DataBinder

public DataBinder(java.lang.Object target,
                  java.lang.String objectName)

Create a new DataBinder instance.

Parameters:

target - the target object to bind onto (or null if the binder is just used to convert a plain parameter value)

objectName - the name of the target object

Method Detail

getTarget

public java.lang.Object getTarget()

Return the wrapped target object.

getObjectName

public java.lang.String getObjectName()

Return the name of the bound object.

setAutoGrowNestedPaths

public void setAutoGrowNestedPaths(boolean autoGrowNestedPaths)

Set whether this binder should attempt to "auto-grow" a nested path that contains a null value.

If "true", a null path location will be populated with a default object value and traversed instead of resulting in an exception. This flag also enables auto-growth of collection elements when accessing an out-of-bounds index.

Default is "true" on a standard DataBinder. Note that since Spring 4.1 this feature is supported for bean property access (DataBinder's default mode) and field access.

See Also:

initBeanPropertyAccess(), ConfigurablePropertyAccessor.setAutoGrowNestedPaths(boolean)

isAutoGrowNestedPaths

public boolean isAutoGrowNestedPaths()

Return whether "auto-growing" of nested paths has been activated.

setAutoGrowCollectionLimit

public void setAutoGrowCollectionLimit(int autoGrowCollectionLimit)

Specify the limit for array and collection auto-growing.

Default is 256, preventing OutOfMemoryErrors in case of large indexes. Raise this limit if your auto-growing needs are unusually high.

getAutoGrowCollectionLimit

public int getAutoGrowCollectionLimit()

Return the current limit for array and collection auto-growing.

initBeanPropertyAccess

public void initBeanPropertyAccess()

Initialize standard JavaBean property access for this DataBinder.

This is the default; an explicit call just leads to eager initialization.

See Also:

initDirectFieldAccess()

initDirectFieldAccess

public void initDirectFieldAccess()

Initialize direct field access for this DataBinder, as alternative to the default bean property access.

See Also:

initBeanPropertyAccess()

getInternalBindingResult

protected AbstractPropertyBindingResult getInternalBindingResult()

Return the internal BindingResult held by this DataBinder, as AbstractPropertyBindingResult.

getPropertyAccessor

protected ConfigurablePropertyAccessor getPropertyAccessor()

Return the underlying PropertyAccessor of this binder's BindingResult.

getSimpleTypeConverter

protected SimpleTypeConverter getSimpleTypeConverter()

Return this binder's underlying SimpleTypeConverter.

getPropertyEditorRegistry

protected PropertyEditorRegistry getPropertyEditorRegistry()

Return the underlying TypeConverter of this binder's BindingResult.

getTypeConverter

protected TypeConverter getTypeConverter()

Return the underlying TypeConverter of this binder's BindingResult.

getBindingResult

public BindingResult getBindingResult()

Return the BindingResult instance created by this DataBinder. This allows for convenient access to the binding results after a bind operation.

Returns:

the BindingResult instance, to be treated as BindingResult or as Errors instance (Errors is a super-interface of BindingResult)

See Also:

Errors, bind(org.springframework.beans.PropertyValues)

setIgnoreUnknownFields

public void setIgnoreUnknownFields(boolean ignoreUnknownFields)

Set whether to ignore unknown fields, that is, whether to ignore bind parameters that do not have corresponding fields in the target object.

Default is "true". Turn this off to enforce that all bind parameters must have a matching field in the target object.

Note that this setting only applies to binding operations on this DataBinder, not to retrieving values via its BindingResult.

See Also:

bind(org.springframework.beans.PropertyValues)

isIgnoreUnknownFields

public boolean isIgnoreUnknownFields()

Return whether to ignore unknown fields when binding.

setIgnoreInvalidFields

public void setIgnoreInvalidFields(boolean ignoreInvalidFields)

Set whether to ignore invalid fields, that is, whether to ignore bind parameters that have corresponding fields in the target object which are not accessible (for example because of null values in the nested path).

Default is "false". Turn this on to ignore bind parameters for nested objects in non-existing parts of the target object graph.

Note that this setting only applies to binding operations on this DataBinder, not to retrieving values via its BindingResult.

See Also:

bind(org.springframework.beans.PropertyValues)

isIgnoreInvalidFields

public boolean isIgnoreInvalidFields()

Return whether to ignore invalid fields when binding.

setAllowedFields

public void setAllowedFields(java.lang.String... allowedFields)

Register fields that should be allowed for binding. Default is all fields. Restrict this for example to avoid unwanted modifications by malicious users when binding HTTP request parameters.

Supports "xxx*", "*xxx" and "*xxx*" patterns. More sophisticated matching can be implemented by overriding the isAllowed method.

Alternatively, specify a list of disallowed fields.

Parameters:

allowedFields - array of field names

See Also:

setDisallowedFields(java.lang.String...), isAllowed(String), ServletRequestDataBinder

getAllowedFields

public java.lang.String[] getAllowedFields()

Return the fields that should be allowed for binding.

Returns:

array of field names

setDisallowedFields

public void setDisallowedFields(java.lang.String... disallowedFields)

Register fields that should not be allowed for binding. Default is none. Mark fields as disallowed for example to avoid unwanted modifications by malicious users when binding HTTP request parameters.

Supports "xxx*", "*xxx" and "*xxx*" patterns. More sophisticated matching can be implemented by overriding the isAllowed method.

Alternatively, specify a list of allowed fields.

Parameters:

disallowedFields - array of field names

See Also:

setAllowedFields(java.lang.String...), isAllowed(String), ServletRequestDataBinder

getDisallowedFields

public java.lang.String[] getDisallowedFields()

Return the fields that should not be allowed for binding.

Returns:

array of field names

setRequiredFields

public void setRequiredFields(java.lang.String... requiredFields)

Register fields that are required for each binding process.

If one of the specified fields is not contained in the list of incoming property values, a corresponding "missing field" error will be created, with error code "required" (by the default binding error processor).

Parameters:

requiredFields - array of field names

See Also:

setBindingErrorProcessor(org.springframework.validation.BindingErrorProcessor), DefaultBindingErrorProcessor.MISSING_FIELD_ERROR_CODE

getRequiredFields

public java.lang.String[] getRequiredFields()

Return the fields that are required for each binding process.

Returns:

array of field names

setExtractOldValueForEditor

public void setExtractOldValueForEditor(boolean extractOldValueForEditor)

Set whether to extract the old field value when applying a property editor to a new value for a field.

Default is "true", exposing previous field values to custom editors. Turn this to "false" to avoid side effects caused by getters.

setMessageCodesResolver

public void setMessageCodesResolver(MessageCodesResolver messageCodesResolver)

Set the strategy to use for resolving errors into message codes. Applies the given strategy to the underlying errors holder.

Default is a DefaultMessageCodesResolver.

See Also:

AbstractBindingResult.setMessageCodesResolver(org.springframework.validation.MessageCodesResolver), DefaultMessageCodesResolver

setBindingErrorProcessor

public void setBindingErrorProcessor(BindingErrorProcessor bindingErrorProcessor)

Set the strategy to use for processing binding errors, that is, required field errors and PropertyAccessExceptions.

Default is a DefaultBindingErrorProcessor.

See Also:

DefaultBindingErrorProcessor

getBindingErrorProcessor

public BindingErrorProcessor getBindingErrorProcessor()

Return the strategy for processing binding errors.

setValidator

public void setValidator(Validator validator)

Set the Validator to apply after each binding step.

See Also:

addValidators(Validator...), replaceValidators(Validator...)

assertValidators

private void assertValidators(Validator... validators)

addValidators

public void addValidators(Validator... validators)

Add Validators to apply after each binding step.

See Also:

setValidator(Validator), replaceValidators(Validator...)

replaceValidators

public void replaceValidators(Validator... validators)

Replace the Validators to apply after each binding step.

See Also:

setValidator(Validator), addValidators(Validator...)

getValidator

public Validator getValidator()

Return the primary Validator to apply after each binding step, if any.

getValidators

public java.util.List<Validator> getValidators()

Return the Validators to apply after data binding.

setConversionService

public void setConversionService(ConversionService conversionService)

Specify a Spring 3.0 ConversionService to use for converting property values, as an alternative to JavaBeans PropertyEditors.

getConversionService

public ConversionService getConversionService()

Return the associated ConversionService, if any.

addCustomFormatter

public void addCustomFormatter(Formatter<?> formatter)

Add a custom formatter, applying it to all fields matching the Formatter-declared type.

Registers a corresponding PropertyEditor adapter underneath the covers.

Parameters:

formatter - the formatter to add, generically declared for a specific type

Since:

4.2

See Also:

registerCustomEditor(Class, PropertyEditor)

addCustomFormatter

public void addCustomFormatter(Formatter<?> formatter,
                               java.lang.String... fields)

Add a custom formatter for the field type specified in Formatter class, applying it to the specified fields only, if any, or otherwise to all fields.

Registers a corresponding PropertyEditor adapter underneath the covers.

Parameters:

formatter - the formatter to add, generically declared for a specific type

fields - the fields to apply the formatter to, or none if to be applied to all

Since:

4.2

See Also:

registerCustomEditor(Class, String, PropertyEditor)

addCustomFormatter

public void addCustomFormatter(Formatter<?> formatter,
                               java.lang.Class<?>... fieldTypes)

Add a custom formatter, applying it to the specified field types only, if any, or otherwise to all fields matching the Formatter-declared type.

Registers a corresponding PropertyEditor adapter underneath the covers.

Parameters:

formatter - the formatter to add (does not need to generically declare a field type if field types are explicitly specified as parameters)

fieldTypes - the field types to apply the formatter to, or none if to be derived from the given Formatter implementation class

Since:

4.2

See Also:

registerCustomEditor(Class, PropertyEditor)

registerCustomEditor

public void registerCustomEditor(java.lang.Class<?> requiredType,
                                 java.beans.PropertyEditor propertyEditor)

Description copied from interface: PropertyEditorRegistry

Register the given custom property editor for all properties of the given type.

Specified by:

registerCustomEditor in interface PropertyEditorRegistry

Parameters:

requiredType - the type of the property

propertyEditor - the editor to register

registerCustomEditor

public void registerCustomEditor(java.lang.Class<?> requiredType,
                                 java.lang.String field,
                                 java.beans.PropertyEditor propertyEditor)

Description copied from interface: PropertyEditorRegistry

Register the given custom property editor for the given type and property, or for all properties of the given type.

If the property path denotes an array or Collection property, the editor will get applied either to the array/Collection itself (the PropertyEditor has to create an array or Collection value) or to each element (the PropertyEditor has to create the element type), depending on the specified required type.

Note: Only one single registered custom editor per property path is supported. In the case of a Collection/array, do not register an editor for both the Collection/array and each element on the same property.

For example, if you wanted to register an editor for "items[n].quantity" (for all values n), you would use "items.quantity" as the value of the 'propertyPath' argument to this method.

Specified by:

registerCustomEditor in interface PropertyEditorRegistry

Parameters:

requiredType - the type of the property. This may be null if a property is given but should be specified in any case, in particular in case of a Collection - making clear whether the editor is supposed to apply to the entire Collection itself or to each of its entries. So as a general rule: Do not specify null here in case of a Collection/array!

field - the path of the property (name or nested path), or null if registering an editor for all properties of the given type

propertyEditor - editor to register

findCustomEditor

public java.beans.PropertyEditor findCustomEditor(java.lang.Class<?> requiredType,
                                                  java.lang.String propertyPath)

Description copied from interface: PropertyEditorRegistry

Find a custom property editor for the given type and property.

Specified by:

findCustomEditor in interface PropertyEditorRegistry

Parameters:

requiredType - the type of the property (can be null if a property is given but should be specified in any case for consistency checking)

propertyPath - the path of the property (name or nested path), or null if looking for an editor for all properties of the given type

Returns:

the registered editor, or null if none

convertIfNecessary

public <T> T convertIfNecessary(java.lang.Object value,
                                java.lang.Class<T> requiredType)
                         throws TypeMismatchException

Description copied from interface: TypeConverter

Convert the value to the required type (if necessary from a String).

Conversions from String to any type will typically use the setAsText method of the PropertyEditor class, or a Spring Converter in a ConversionService.

Specified by:

convertIfNecessary in interface TypeConverter

Parameters:

value - the value to convert

requiredType - the type we must convert to (or null if not known, for example in case of a collection element)

Returns:

the new value, possibly the result of type conversion

Throws:

TypeMismatchException - if type conversion failed

See Also:

PropertyEditor.setAsText(String), PropertyEditor.getValue(), ConversionService, Converter

convertIfNecessary

public <T> T convertIfNecessary(java.lang.Object value,
                                java.lang.Class<T> requiredType,
                                MethodParameter methodParam)
                         throws TypeMismatchException

Description copied from interface: TypeConverter

Convert the value to the required type (if necessary from a String).

Conversions from String to any type will typically use the setAsText method of the PropertyEditor class, or a Spring Converter in a ConversionService.

Specified by:

convertIfNecessary in interface TypeConverter

Parameters:

value - the value to convert

requiredType - the type we must convert to (or null if not known, for example in case of a collection element)

methodParam - the method parameter that is the target of the conversion (for analysis of generic types; may be null)

Returns:

the new value, possibly the result of type conversion

Throws:

TypeMismatchException - if type conversion failed

See Also:

PropertyEditor.setAsText(String), PropertyEditor.getValue(), ConversionService, Converter

convertIfNecessary

public <T> T convertIfNecessary(java.lang.Object value,
                                java.lang.Class<T> requiredType,
                                java.lang.reflect.Field field)
                         throws TypeMismatchException

Description copied from interface: TypeConverter

Convert the value to the required type (if necessary from a String).

Conversions from String to any type will typically use the setAsText method of the PropertyEditor class, or a Spring Converter in a ConversionService.

Specified by:

convertIfNecessary in interface TypeConverter

Parameters:

value - the value to convert

requiredType - the type we must convert to (or null if not known, for example in case of a collection element)

field - the reflective field that is the target of the conversion (for analysis of generic types; may be null)

Returns:

the new value, possibly the result of type conversion

Throws:

TypeMismatchException - if type conversion failed

See Also:

PropertyEditor.setAsText(String), PropertyEditor.getValue(), ConversionService, Converter

bind

public void bind(PropertyValues pvs)

Bind the given property values to this binder's target.

This call can create field errors, representing basic binding errors like a required field (code "required"), or type mismatch between value and bean property (code "typeMismatch").

Note that the given PropertyValues should be a throwaway instance: For efficiency, it will be modified to just contain allowed fields if it implements the MutablePropertyValues interface; else, an internal mutable copy will be created for this purpose. Pass in a copy of the PropertyValues if you want your original instance to stay unmodified in any case.

Parameters:

pvs - property values to bind

See Also:

doBind(org.springframework.beans.MutablePropertyValues)

doBind

protected void doBind(MutablePropertyValues mpvs)

Actual implementation of the binding process, working with the passed-in MutablePropertyValues instance.

Parameters:

mpvs - the property values to bind, as MutablePropertyValues instance

See Also:

checkAllowedFields(org.springframework.beans.MutablePropertyValues), checkRequiredFields(org.springframework.beans.MutablePropertyValues), applyPropertyValues(org.springframework.beans.MutablePropertyValues)

checkAllowedFields

protected void checkAllowedFields(MutablePropertyValues mpvs)

Check the given property values against the allowed fields, removing values for fields that are not allowed.

Parameters:

mpvs - the property values to be bound (can be modified)

See Also:

getAllowedFields(), isAllowed(String)

isAllowed

protected boolean isAllowed(java.lang.String field)

Return if the given field is allowed for binding. Invoked for each passed-in property value.

The default implementation checks for "xxx*", "*xxx" and "*xxx*" matches, as well as direct equality, in the specified lists of allowed fields and disallowed fields. A field matching a disallowed pattern will not be accepted even if it also happens to match a pattern in the allowed list.

Can be overridden in subclasses.

Parameters:

field - the field to check

Returns:

if the field is allowed

See Also:

setAllowedFields(java.lang.String...), setDisallowedFields(java.lang.String...), PatternMatchUtils.simpleMatch(String, String)

checkRequiredFields

protected void checkRequiredFields(MutablePropertyValues mpvs)

Check the given property values against the required fields, generating missing field errors where appropriate.

Parameters:

mpvs - the property values to be bound (can be modified)

See Also:

getRequiredFields(), getBindingErrorProcessor(), BindingErrorProcessor.processMissingFieldError(java.lang.String, org.springframework.validation.BindingResult)

applyPropertyValues

protected void applyPropertyValues(MutablePropertyValues mpvs)

Apply given property values to the target object.

Default implementation applies all of the supplied property values as bean property values. By default, unknown fields will be ignored.

Parameters:

mpvs - the property values to be bound (can be modified)

See Also:

getTarget(), getPropertyAccessor(), isIgnoreUnknownFields(), getBindingErrorProcessor(), BindingErrorProcessor.processPropertyAccessException(org.springframework.beans.PropertyAccessException, org.springframework.validation.BindingResult)

validate

public void validate()

Invoke the specified Validators, if any.

See Also:

setValidator(Validator), getBindingResult()

validate

public void validate(java.lang.Object... validationHints)

Invoke the specified Validators, if any, with the given validation hints.

Note: Validation hints may get ignored by the actual target Validator.

Parameters:

validationHints - one or more hint objects to be passed to a SmartValidator

See Also:

setValidator(Validator), SmartValidator.validate(Object, Errors, Object...)

close

public java.util.Map<?,?> close()
                         throws BindException

Close this DataBinder, which may result in throwing a BindException if it encountered any errors.

Returns:

the model Map, containing target object and Errors instance

Throws:

BindException - if there were any errors in the bind operation

See Also:

BindingResult.getModel()