org.springframework.beans
Class BeanWrapperImpl

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

All Implemented Interfaces:

BeanWrapper, PropertyAccessor

public class BeanWrapperImpl

extends Object

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 BeanWrapper's registerCustomEditor method to register an editor for the particular instance (i.e. they're not shared across the application).

BeanWrapperImpl will convert collection and array values to the corresponding target collections or arrays, if necessary. Custom property editors that deal with Lists or arrays can be written against a comma-delimited String 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, Jean-Pierre Pawlak

See Also:

registerCustomEditor(java.lang.Class, java.beans.PropertyEditor), PropertyEditorManager, ByteArrayPropertyEditor, ClassEditor, FileEditor, InputStreamEditor, LocaleEditor, PropertiesEditor, StringArrayPropertyEditor, URLEditor, CustomBooleanEditor, CustomNumberEditor

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(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)
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.
PropertyEditor	findCustomEditor(Class requiredType, String propertyPath) Find a custom property editor for the given type and property.
protected BeanWrapperImpl	getBeanWrapperForPropertyPath(String propertyPath) Recursively navigate to return a BeanWrapper for the nested property path.
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 a particular property, either checking the property descriptor or checking the value in case of an indexed or mapped element.
protected Object	getPropertyValue(org.springframework.beans.BeanWrapperImpl.PropertyTokenHolder tokens)
Object	getPropertyValue(String propertyName) Get the value of a property.
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	isReadableProperty(String propertyName) Return whether this property is readable.
boolean	isWritableProperty(String propertyName) Return whether this property is writable.
void	registerCustomEditor(Class requiredType, PropertyEditor propertyEditor) Register the given custom property editor for all properties of the given type.
void	registerCustomEditor(Class requiredType, String propertyPath, PropertyEditor propertyEditor) Register the given custom property editor for the given type and property, or for all properties of the given type.
protected void	setIntrospectionClass(Class clazz) Set the class to introspect.
protected void	setPropertyValue(org.springframework.beans.BeanWrapperImpl.PropertyTokenHolder tokens, Object value)
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) 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() This method is expensive!

Methods inherited from class java.lang.Object

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

Constructor Detail

BeanWrapperImpl

public BeanWrapperImpl()

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

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)

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

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)

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

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

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

registerCustomEditor

public void registerCustomEditor(Class requiredType,
                                 PropertyEditor propertyEditor)

Description copied from interface: BeanWrapper

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

Specified by:

registerCustomEditor in interface BeanWrapper

Parameters:

requiredType - type of the property

propertyEditor - editor to register

registerCustomEditor

public void registerCustomEditor(Class requiredType,
                                 String propertyPath,
                                 PropertyEditor propertyEditor)

Description copied from interface: BeanWrapper

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 case of a Collection/array, do not register an editor for both the Collection/array and each element on the same property.

Specified by:

registerCustomEditor in interface BeanWrapper

Parameters:

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

propertyPath - 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 PropertyEditor findCustomEditor(Class requiredType,
                                       String propertyPath)

Description copied from interface: BeanWrapper

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

Specified by:

findCustomEditor in interface BeanWrapper

Parameters:

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

propertyPath - 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

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

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:

BeansException

getPropertyValue

protected Object getPropertyValue(org.springframework.beans.BeanWrapperImpl.PropertyTokenHolder tokens)
                           throws BeansException

Throws:

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:

BeansException

setPropertyValue

protected void setPropertyValue(org.springframework.beans.BeanWrapperImpl.PropertyTokenHolder tokens,
                                Object value)
                         throws BeansException

Throws:

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:

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:

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:

BeansException

doTypeConversionIfNecessary

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

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 this class for this to work. This is a standard Java Beans API. A number of property editors are automatically registered by this class.

Parameters:

newValue - proposed change value.

requiredType - type we must convert to

Returns:

new value, possibly the result of type convertion

Throws:

BeansException - if there is an internal error

doTypeConversionIfNecessary

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

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 - type we must convert to

Returns:

converted value (i.e. possibly the result of type conversion)

Throws:

BeansException - if there is an internal error

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:

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

getPropertyType

public Class getPropertyType(String propertyName)
                      throws BeansException

Description copied from interface: BeanWrapper

Determine the property type for a particular property, either checking the property descriptor or checking the value in case of an indexed or mapped element.

Specified by:

getPropertyType in interface BeanWrapper

Parameters:

propertyName - property to check status for

Returns:

the property type for the particular property, or null if not determinable (can only happen with an indexed or mapped element)

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

toString

public String toString()

This method is expensive! Only call for diagnostics and debugging reasons, not in production.

Returns:

a string describing the state of this object