org.springframework.beans
Class BeanWrapperImpl

java.lang.Object
  org.springframework.beans.PropertyEditorRegistrySupport
      org.springframework.beans.BeanWrapperImpl

All Implemented Interfaces:

BeanWrapper, PropertyAccessor, PropertyEditorRegistry

public class BeanWrapperImpl
extends PropertyEditorRegistrySupport
implements BeanWrapper

Default implementation of the BeanWrapper interface that should be sufficient for all typical use cases. Caches introspection results for efficiency.

Note: This class never tries to load a class by name, as this can pose class loading problems in J2EE applications with multiple deployment modules. The caller is responsible for loading a target class.

Note: Auto-registers default property editors from the org.springframework.beans.propertyeditors package, which apply in addition to the JDK's standard PropertyEditors. Applications can call the registerCustomEditor method to register an editor for a particular instance (i.e. they're not shared across the application). See the base class PropertyEditorRegistrySupport for details.

BeanWrapperImpl will convert collection and array values to the corresponding target collections or arrays, if necessary. Custom property editors that deal with collections or arrays can either be written via PropertyEditor's setValue, or against a comma-delimited String via setAsText, as String arrays are converted in such a format if the array itself is not assignable.

Since:

15 April 2001

Author:

Rod Johnson, Juergen Hoeller, Rob Harrop

See Also:

PropertyEditorRegistrySupport.registerCustomEditor(java.lang.Class, java.beans.PropertyEditor), setPropertyValues(java.util.Map), setPropertyValue(java.lang.String, java.lang.Object), getPropertyValue(java.lang.String), getPropertyType(java.lang.String), BeanWrapper, PropertyEditorRegistrySupport

Field Summary

Fields inherited from interface org.springframework.beans.PropertyAccessor

NESTED_PROPERTY_SEPARATOR, NESTED_PROPERTY_SEPARATOR_CHAR, PROPERTY_KEY_PREFIX, PROPERTY_KEY_PREFIX_CHAR, PROPERTY_KEY_SUFFIX, PROPERTY_KEY_SUFFIX_CHAR

Constructor Summary

BeanWrapperImpl()
Create new empty BeanWrapperImpl.

BeanWrapperImpl(boolean registerDefaultEditors)
Create new empty BeanWrapperImpl.

BeanWrapperImpl(Class clazz)
Create new BeanWrapperImpl, wrapping a new instance of the specified class.

BeanWrapperImpl(Object object)
Create new BeanWrapperImpl for the given object.

BeanWrapperImpl(Object object, String nestedPath, Object rootObject)
Create new BeanWrapperImpl for the given object, registering a nested path that the object is in.

Method Summary

Object	doTypeConversionIfNecessary(Object newValue, Class requiredType) Convert the value to the required type (if necessary from a String).
protected Object	doTypeConversionIfNecessary(String propertyName, String fullPropertyName, Object oldValue, Object newValue, Class requiredType) Convert the value to the required type (if necessary from a String), for the specified property.
protected BeanWrapperImpl	getBeanWrapperForPropertyPath(String propertyPath) Recursively navigate to return a BeanWrapper for the nested property path.
String	getNestedPath() Return the nested path of the object wrapped by this BeanWrapper.
PropertyDescriptor	getPropertyDescriptor(String propertyName) Get the property descriptor for a particular property.
protected PropertyDescriptor	getPropertyDescriptorInternal(String propertyName) Internal version of getPropertyDescriptor: Returns null if not found rather than throwing an exception.
PropertyDescriptor[]	getPropertyDescriptors() Get the PropertyDescriptors identified on this object (standard JavaBeans introspection).
Class	getPropertyType(String propertyName) Determine the property type for the given property path.
Object	getPropertyValue(String propertyName) Get the value of a property.
Class	getRootClass() Return the class of the root object at the top of the path of this BeanWrapper.
Object	getRootInstance() Return the root object at the top of the path of this BeanWrapper.
Class	getWrappedClass() Convenience method to return the class of the wrapped object.
Object	getWrappedInstance() Return the bean wrapped by this object (cannot be null).
boolean	isExtractOldValueForEditor() Return whether to extract the old property value when applying a property editor to a new value for a property.
boolean	isReadableProperty(String propertyName) Return whether this property is readable.
boolean	isWritableProperty(String propertyName) Return whether this property is writable.
protected BeanWrapperImpl	newNestedBeanWrapper(Object object, String nestedPath) Create a new nested BeanWrapper instance.
void	setExtractOldValueForEditor(boolean extractOldValueForEditor) Set whether to extract the old property value when applying a property editor to a new value for a property.
protected void	setIntrospectionClass(Class clazz) Set the class to introspect.
void	setPropertyValue(PropertyValue pv) Update a property value.
void	setPropertyValue(String propertyName, Object value) Set a property value.
void	setPropertyValues(Map map) Bulk update from a Map.
void	setPropertyValues(PropertyValues pvs) The preferred way to perform a bulk update.
void	setPropertyValues(PropertyValues propertyValues, boolean ignoreUnknown) Perform a bulk update with full control over behavior.
void	setWrappedInstance(Object object) Switch the target object, replacing the cached introspection results only if the class of the new object is different to that of the replaced object.
void	setWrappedInstance(Object object, String nestedPath, Object rootObject) Switch the target object, replacing the cached introspection results only if the class of the new object is different to that of the replaced object.
String	toString()

Methods inherited from class org.springframework.beans.PropertyEditorRegistrySupport

copyCustomEditorsTo, copyDefaultEditorsTo, findCustomEditor, getDefaultEditor, guessPropertyTypeFromEditors, registerCustomEditor, registerCustomEditor, registerDefaultEditors

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.beans.PropertyEditorRegistry

findCustomEditor, registerCustomEditor, registerCustomEditor

Constructor Detail

BeanWrapperImpl

public BeanWrapperImpl()

Create new empty BeanWrapperImpl. Wrapped instance needs to be set afterwards. Registers default editors.

See Also:

setWrappedInstance(java.lang.Object)

BeanWrapperImpl

public BeanWrapperImpl(boolean registerDefaultEditors)

Create new empty BeanWrapperImpl. Wrapped instance needs to be set afterwards.

Parameters:

registerDefaultEditors - whether to register default editors (can be suppressed if the BeanWrapper won't need any type conversion)

See Also:

setWrappedInstance(java.lang.Object)

BeanWrapperImpl

public BeanWrapperImpl(Object object)

Create new BeanWrapperImpl for the given object.

Parameters:

object - object wrapped by this BeanWrapper

BeanWrapperImpl

public BeanWrapperImpl(Class clazz)

Create new BeanWrapperImpl, wrapping a new instance of the specified class.

Parameters:

clazz - class to instantiate and wrap

BeanWrapperImpl

public BeanWrapperImpl(Object object,
                       String nestedPath,
                       Object rootObject)

Create new BeanWrapperImpl for the given object, registering a nested path that the object is in.

Parameters:

object - object wrapped by this BeanWrapper

nestedPath - the nested path of the object

rootObject - the root object at the top of the path

Method Detail

setWrappedInstance

public void setWrappedInstance(Object object)

Switch the target object, replacing the cached introspection results only if the class of the new object is different to that of the replaced object.

Specified by:

setWrappedInstance in interface BeanWrapper

Parameters:

object - new target

setWrappedInstance

public void setWrappedInstance(Object object,
                               String nestedPath,
                               Object rootObject)

Switch the target object, replacing the cached introspection results only if the class of the new object is different to that of the replaced object.

Parameters:

object - new target

nestedPath - the nested path of the object

rootObject - the root object at the top of the path

getWrappedInstance

public Object getWrappedInstance()

Description copied from interface: BeanWrapper

Return the bean wrapped by this object (cannot be null).

Specified by:

getWrappedInstance in interface BeanWrapper

Returns:

the bean wrapped by this object

getWrappedClass

public Class getWrappedClass()

Description copied from interface: BeanWrapper

Convenience method to return the class of the wrapped object.

Specified by:

getWrappedClass in interface BeanWrapper

Returns:

the class of the wrapped object

getNestedPath

public String getNestedPath()

Return the nested path of the object wrapped by this BeanWrapper.

getRootInstance

public Object getRootInstance()

Return the root object at the top of the path of this BeanWrapper.

See Also:

getNestedPath()

getRootClass

public Class getRootClass()

Return the class of the root object at the top of the path of this BeanWrapper.

See Also:

getNestedPath()

setIntrospectionClass

protected void setIntrospectionClass(Class clazz)

Set the class to introspect. Needs to be called when the target object changes.

Parameters:

clazz - the class to introspect

setExtractOldValueForEditor

public void setExtractOldValueForEditor(boolean extractOldValueForEditor)

Description copied from interface: BeanWrapper

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

Default is "false", avoiding side effects caused by getters. Turn this to "true" to expose previous property values to custom editors.

Specified by:

setExtractOldValueForEditor in interface BeanWrapper

isExtractOldValueForEditor

public boolean isExtractOldValueForEditor()

Description copied from interface: BeanWrapper

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

Specified by:

isExtractOldValueForEditor in interface BeanWrapper

getPropertyDescriptors

public PropertyDescriptor[] getPropertyDescriptors()

Description copied from interface: BeanWrapper

Get the PropertyDescriptors identified on this object (standard JavaBeans introspection).

Specified by:

getPropertyDescriptors in interface BeanWrapper

Returns:

the PropertyDescriptors identified on this object

getPropertyDescriptor

public PropertyDescriptor getPropertyDescriptor(String propertyName)
                                         throws BeansException

Description copied from interface: BeanWrapper

Get the property descriptor for a particular property.

Specified by:

getPropertyDescriptor in interface BeanWrapper

Parameters:

propertyName - property to check status for

Returns:

the property descriptor for the particular property

Throws:

InvalidPropertyException - if there is no such property

BeansException

getPropertyDescriptorInternal

protected PropertyDescriptor getPropertyDescriptorInternal(String propertyName)
                                                    throws BeansException

Internal version of getPropertyDescriptor: Returns null if not found rather than throwing an exception.

Throws:

BeansException

isReadableProperty

public boolean isReadableProperty(String propertyName)

Description copied from interface: BeanWrapper

Return whether this property is readable. Returns false if the property doesn't exist.

Specified by:

isReadableProperty in interface BeanWrapper

Parameters:

propertyName - property to check status for

Returns:

whether this property is readable

isWritableProperty

public boolean isWritableProperty(String propertyName)

Description copied from interface: BeanWrapper

Return whether this property is writable. Returns false if the property doesn't exist.

Specified by:

isWritableProperty in interface BeanWrapper

Parameters:

propertyName - property to check status for

Returns:

whether this property is writable

getPropertyType

public Class getPropertyType(String propertyName)
                      throws BeansException

Description copied from class: PropertyEditorRegistrySupport

Determine the property type for the given property path. Called by findCustomEditor if no required type has been specified, to be able to find a type-specific editor even if just given a property path.

Default implementation always returns null. BeanWrapperImpl overrides this with the standard getPropertyType method as defined by the BeanWrapper interface.

Specified by:

getPropertyType in interface BeanWrapper

Overrides:

getPropertyType in class PropertyEditorRegistrySupport

Parameters:

propertyName - the property path to determine the type for

Returns:

the type of the property, or null if not determinable

Throws:

InvalidPropertyException - if there is no such property

BeansException

See Also:

BeanWrapper.getPropertyType(String)

getBeanWrapperForPropertyPath

protected BeanWrapperImpl getBeanWrapperForPropertyPath(String propertyPath)
                                                 throws BeansException

Recursively navigate to return a BeanWrapper for the nested property path.

Parameters:

propertyPath - property property path, which may be nested

Returns:

a BeanWrapper for the target bean

Throws:

BeansException

newNestedBeanWrapper

protected BeanWrapperImpl newNestedBeanWrapper(Object object,
                                               String nestedPath)

Create a new nested BeanWrapper instance.

Default implementation creates a BeanWrapperImpl instance. Can be overridden in subclasses to create a BeanWrapperImpl subclass.

Parameters:

object - object wrapped by this BeanWrapper

nestedPath - the nested path of the object

Returns:

the nested BeanWrapper instance

getPropertyValue

public Object getPropertyValue(String propertyName)
                        throws BeansException

Description copied from interface: PropertyAccessor

Get the value of a property.

Specified by:

getPropertyValue in interface PropertyAccessor

Parameters:

propertyName - name of the property to get the value of

Returns:

the value of the property

Throws:

FatalBeanException - if there is no such property, if the property isn't readable, or if the property getter throws an exception.

BeansException

setPropertyValue

public void setPropertyValue(String propertyName,
                             Object value)
                      throws BeansException

Description copied from interface: PropertyAccessor

Set a property value. This method is provided for convenience only. The setPropertyValue(PropertyValue) method is more powerful.

Specified by:

setPropertyValue in interface PropertyAccessor

Parameters:

propertyName - name of the property to set value of

value - the new value

Throws:

FatalBeanException - if there is no such property, if the property isn't writable, or if the property setter throws an exception.

BeansException

setPropertyValue

public void setPropertyValue(PropertyValue pv)
                      throws BeansException

Description copied from interface: PropertyAccessor

Update a property value. This is the preferred way to update an individual property.

Specified by:

setPropertyValue in interface PropertyAccessor

Parameters:

pv - object containing new property value

Throws:

FatalBeanException - if there is no such property, if the property isn't writable, or if the property setter throws an exception.

BeansException

setPropertyValues

public void setPropertyValues(Map map)
                       throws BeansException

Bulk update from a Map. Bulk updates from PropertyValues are more powerful: this method is provided for convenience.

Specified by:

setPropertyValues in interface PropertyAccessor

Parameters:

map - map containing properties to set, as name-value pairs. The map may include nested properties.

Throws:

BeansException - if there's a fatal, low-level exception

setPropertyValues

public void setPropertyValues(PropertyValues pvs)
                       throws BeansException

Description copied from interface: PropertyAccessor

The preferred way to perform a bulk update.

Note that performing a bulk update differs from performing a single update, in that an implementation of this class will continue to update properties if a recoverable error (such as a type mismatch, but not an invalid field name or the like) is encountered, throwing a PropertyAccessExceptionsException containing all the individual errors. This exception can be examined later to see all binding errors. Properties that were successfully updated stay changed.

Does not allow unknown fields. Equivalent to setPropertyValues(pvs, false).

Specified by:

setPropertyValues in interface PropertyAccessor

Parameters:

pvs - PropertyValues to set on the target object

Throws:

FatalBeanException - if there is no such property, if the property isn't writable, or if the property setter throws an exception.

BeansException

See Also:

PropertyAccessor.setPropertyValues(PropertyValues, boolean)

setPropertyValues

public void setPropertyValues(PropertyValues propertyValues,
                              boolean ignoreUnknown)
                       throws BeansException

Description copied from interface: PropertyAccessor

Perform a bulk update with full control over behavior.

Note that performing a bulk update differs from performing a single update, in that an implementation of this class will continue to update properties if a recoverable error (such as a type mismatch, but not an invalid field name or the like) is encountered, throwing a PropertyAccessExceptionsException containing all the individual errors. This exception can be examined later to see all binding errors. Properties that were successfully updated stay changed.

Does not allow unknown fields.

Specified by:

setPropertyValues in interface PropertyAccessor

Parameters:

propertyValues - PropertyValues to set on the target object

ignoreUnknown - should we ignore unknown values (not found in the bean)

Throws:

FatalBeanException - if there is no such property, if the property isn't writable, or if the property setter throws an exception.

BeansException

doTypeConversionIfNecessary

public Object doTypeConversionIfNecessary(Object newValue,
                                          Class requiredType)
                                   throws TypeMismatchException

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

Conversions from String to any type use the setAsText method of the PropertyEditor class. Note that a PropertyEditor must be registered for the given class for this to work; this is a standard JavaBeans API. A number of PropertyEditors are automatically registered by BeanWrapperImpl.

Parameters:

newValue - proposed change value

requiredType - the type we must convert to

Returns:

the new value, possibly the result of type conversion

Throws:

TypeMismatchException - if type conversion failed

See Also:

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

doTypeConversionIfNecessary

protected Object doTypeConversionIfNecessary(String propertyName,
                                             String fullPropertyName,
                                             Object oldValue,
                                             Object newValue,
                                             Class requiredType)
                                      throws TypeMismatchException

Convert the value to the required type (if necessary from a String), for the specified property.

Parameters:

propertyName - name of the property

oldValue - previous value, if available (may be null)

newValue - proposed change value

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

toString

public String toString()

Overrides:

toString in class Object