org.springframework.beans
Class BeanWrapperImpl

java.lang.Object
  extended by org.springframework.beans.PropertyEditorRegistrySupport
      extended by org.springframework.beans.AbstractPropertyAccessor
          extended by org.springframework.beans.BeanWrapperImpl
All Implemented Interfaces:
BeanWrapper, ConfigurablePropertyAccessor, PropertyAccessor, PropertyEditorRegistry, TypeConverter

public class BeanWrapperImpl
extends AbstractPropertyAccessor
implements BeanWrapper

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

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 PropertyEditorRegistrySupport.registerCustomEditor(Class, java.beans.PropertyEditor) method to register an editor for a particular instance (i.e. they are 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.

NOTE: As of Spring 2.5, this is - for almost all purposes - an internal class. It is just public in order to allow for access from other framework packages. For standard application access purposes, use the PropertyAccessorFactory.forBeanPropertyAccess(java.lang.Object) factory method instead.

Since:
15 April 2001
Author:
Rod Johnson, Juergen Hoeller, Rob Harrop
See Also:
PropertyEditorRegistrySupport.registerCustomEditor(java.lang.Class, java.beans.PropertyEditor), AbstractPropertyAccessor.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 convertForProperty(Object value, String propertyName)
          Convert the given value for the specified property to the latter's type.
<T> T
convertIfNecessary(Object value, Class<T> requiredType, MethodParameter methodParam)
          Convert the value to the required type (if necessary from a String).
 int getAutoGrowCollectionLimit()
          Return the limit for array and collection auto-growing.
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)
          Obtain the property descriptor for a specific property of the wrapped object.
protected  PropertyDescriptor getPropertyDescriptorInternal(String propertyName)
          Internal version of getPropertyDescriptor(java.lang.String): Returns null if not found rather than throwing an exception.
 PropertyDescriptor[] getPropertyDescriptors()
          Obtain the PropertyDescriptors for the wrapped object (as determined by standard JavaBeans introspection).
 Class getPropertyType(String propertyName)
          Determine the property type for the given property path.
 TypeDescriptor getPropertyTypeDescriptor(String propertyName)
          Return a type descriptor for the specified property: preferably from the read method, falling back to the write method.
 Object getPropertyValue(String propertyName)
          Actually 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.
 AccessControlContext getSecurityContext()
          Return the security context used during the invocation of the wrapped instance methods.
 Class getWrappedClass()
          Return the type of the wrapped JavaBean object.
 Object getWrappedInstance()
          Return the bean instance wrapped by this object, if any.
 boolean isAutoGrowNestedPaths()
          Return whether "auto-growing" of nested paths has been activated.
 boolean isReadableProperty(String propertyName)
          Determine whether the specified property is readable.
 boolean isWritableProperty(String propertyName)
          Determine whether the specified property is writable.
protected  BeanWrapperImpl newNestedBeanWrapper(Object object, String nestedPath)
          Create a new nested BeanWrapper instance.
 void setAutoGrowCollectionLimit(int autoGrowCollectionLimit)
          Specify a limit for array and collection auto-growing.
 void setAutoGrowNestedPaths(boolean autoGrowNestedPaths)
          Set whether this BeanWrapper should attempt to "auto-grow" a nested path that contains a null value.
protected  void setIntrospectionClass(Class clazz)
          Set the class to introspect.
 void setPropertyValue(PropertyValue pv)
          Set the specified value as current property value.
 void setPropertyValue(String propertyName, Object value)
          Actually set a property value.
 void setSecurityContext(AccessControlContext acc)
          Set the security context used during the invocation of the wrapped instance methods.
 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.AbstractPropertyAccessor
convertIfNecessary, isExtractOldValueForEditor, setExtractOldValueForEditor, setPropertyValues, setPropertyValues, setPropertyValues, setPropertyValues
 
Methods inherited from class org.springframework.beans.PropertyEditorRegistrySupport
copyCustomEditorsTo, copyDefaultEditorsTo, findCustomEditor, getConversionService, getDefaultEditor, guessPropertyTypeFromEditors, hasCustomEditorForElement, isSharedEditor, overrideDefaultEditor, registerCustomEditor, registerCustomEditor, registerDefaultEditors, registerSharedEditor, setConversionService, useConfigValueEditors
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface org.springframework.beans.ConfigurablePropertyAccessor
getConversionService, isExtractOldValueForEditor, setConversionService, setExtractOldValueForEditor
 
Methods inherited from interface org.springframework.beans.PropertyAccessor
setPropertyValues, setPropertyValues, setPropertyValues, setPropertyValues
 
Methods inherited from interface org.springframework.beans.PropertyEditorRegistry
findCustomEditor, registerCustomEditor, registerCustomEditor
 
Methods inherited from interface org.springframework.beans.TypeConverter
convertIfNecessary
 

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.

Parameters:
object - the new target object

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 - the new target object
nestedPath - the nested path of the object
rootObject - the root object at the top of the path

getWrappedInstance

public final Object getWrappedInstance()
Description copied from interface: BeanWrapper
Return the bean instance wrapped by this object, if any.

Specified by:
getWrappedInstance in interface BeanWrapper
Returns:
the bean instance, or null if none set

getWrappedClass

public final Class getWrappedClass()
Description copied from interface: BeanWrapper
Return the type of the wrapped JavaBean object.

Specified by:
getWrappedClass in interface BeanWrapper
Returns:
the type of the wrapped bean instance, or null if no wrapped object has been set

getNestedPath

public final String getNestedPath()
Return the nested path of the object wrapped by this BeanWrapper.


getRootInstance

public final Object getRootInstance()
Return the root object at the top of the path of this BeanWrapper.

See Also:
getNestedPath()

getRootClass

public final Class getRootClass()
Return the class of the root object at the top of the path of this BeanWrapper.

See Also:
getNestedPath()

setAutoGrowNestedPaths

public void setAutoGrowNestedPaths(boolean autoGrowNestedPaths)
Set whether this BeanWrapper 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 a NullValueInNestedPathException. Turning this flag on also enables auto-growth of collection elements when accessing an out-of-bounds index.

Default is "false" on a plain BeanWrapper.

Specified by:
setAutoGrowNestedPaths in interface BeanWrapper

isAutoGrowNestedPaths

public boolean isAutoGrowNestedPaths()
Return whether "auto-growing" of nested paths has been activated.

Specified by:
isAutoGrowNestedPaths in interface BeanWrapper

setAutoGrowCollectionLimit

public void setAutoGrowCollectionLimit(int autoGrowCollectionLimit)
Specify a limit for array and collection auto-growing.

Default is unlimited on a plain BeanWrapper.

Specified by:
setAutoGrowCollectionLimit in interface BeanWrapper

getAutoGrowCollectionLimit

public int getAutoGrowCollectionLimit()
Return the limit for array and collection auto-growing.

Specified by:
getAutoGrowCollectionLimit in interface BeanWrapper

setSecurityContext

public void setSecurityContext(AccessControlContext acc)
Set the security context used during the invocation of the wrapped instance methods. Can be null.


getSecurityContext

public AccessControlContext getSecurityContext()
Return the security context used during the invocation of the wrapped instance methods. Can be null.


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

getPropertyDescriptors

public PropertyDescriptor[] getPropertyDescriptors()
Description copied from interface: BeanWrapper
Obtain the PropertyDescriptors for the wrapped object (as determined by standard JavaBeans introspection).

Specified by:
getPropertyDescriptors in interface BeanWrapper
Returns:
the PropertyDescriptors for the wrapped object

getPropertyDescriptor

public PropertyDescriptor getPropertyDescriptor(String propertyName)
                                         throws BeansException
Description copied from interface: BeanWrapper
Obtain the property descriptor for a specific property of the wrapped object.

Specified by:
getPropertyDescriptor in interface BeanWrapper
Parameters:
propertyName - the property to obtain the descriptor for (may be a nested path, but no indexed/mapped property)
Returns:
the property descriptor for the specified property
Throws:
InvalidPropertyException - if there is no such property
BeansException

getPropertyDescriptorInternal

protected PropertyDescriptor getPropertyDescriptorInternal(String propertyName)
                                                    throws BeansException
Internal version of getPropertyDescriptor(java.lang.String): Returns null if not found rather than throwing an exception.

Parameters:
propertyName - the property to obtain the descriptor for
Returns:
the property descriptor for the specified property, or null if not found
Throws:
BeansException - in case of introspection failure

getPropertyType

public Class getPropertyType(String propertyName)
                      throws BeansException
Description copied from class: PropertyEditorRegistrySupport
Determine the property type for the given property path.

Called by PropertyEditorRegistrySupport.findCustomEditor(java.lang.Class, java.lang.String) if no required type has been specified, to be able to find a type-specific editor even if just given a property path.

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

Specified by:
getPropertyType in interface PropertyAccessor
Overrides:
getPropertyType in class AbstractPropertyAccessor
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 or if the property isn't readable
PropertyAccessException - if the property was valid but the accessor method failed
BeansException
See Also:
PropertyAccessor.getPropertyType(String)

getPropertyTypeDescriptor

public TypeDescriptor getPropertyTypeDescriptor(String propertyName)
                                         throws BeansException
Description copied from interface: PropertyAccessor
Return a type descriptor for the specified property: preferably from the read method, falling back to the write method.

Specified by:
getPropertyTypeDescriptor in interface PropertyAccessor
Parameters:
propertyName - the property to check (may be a nested path and/or an indexed/mapped property)
Returns:
the property type for the particular property, or null if not determinable
Throws:
InvalidPropertyException - if there is no such property or if the property isn't readable
BeansException

isReadableProperty

public boolean isReadableProperty(String propertyName)
Description copied from interface: PropertyAccessor
Determine whether the specified property is readable.

Returns false if the property doesn't exist.

Specified by:
isReadableProperty in interface PropertyAccessor
Parameters:
propertyName - the property to check (may be a nested path and/or an indexed/mapped property)
Returns:
whether the property is readable

isWritableProperty

public boolean isWritableProperty(String propertyName)
Description copied from interface: PropertyAccessor
Determine whether the specified property is writable.

Returns false if the property doesn't exist.

Specified by:
isWritableProperty in interface PropertyAccessor
Parameters:
propertyName - the property to check (may be a nested path and/or an indexed/mapped property)
Returns:
whether the property is writable

convertIfNecessary

public <T> T convertIfNecessary(Object value,
                                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. 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.

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()

convertForProperty

public Object convertForProperty(Object value,
                                 String propertyName)
                          throws TypeMismatchException
Convert the given value for the specified property to the latter's type.

This method is only intended for optimizations in a BeanFactory. Use the convertIfNecessary methods for programmatic conversion.

Parameters:
value - the value to convert
propertyName - the target property (note that nested or indexed properties are not supported here)
Returns:
the new value, possibly the result of type conversion
Throws:
TypeMismatchException - if type conversion failed

getBeanWrapperForPropertyPath

protected BeanWrapperImpl getBeanWrapperForPropertyPath(String propertyPath)
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

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 class: AbstractPropertyAccessor
Actually get the value of a property.

Specified by:
getPropertyValue in interface PropertyAccessor
Specified by:
getPropertyValue in class AbstractPropertyAccessor
Parameters:
propertyName - name of the property to get the value of
Returns:
the value of the property
Throws:
InvalidPropertyException - if there is no such property or if the property isn't readable
PropertyAccessException - if the property was valid but the accessor method failed
BeansException

setPropertyValue

public void setPropertyValue(String propertyName,
                             Object value)
                      throws BeansException
Description copied from class: AbstractPropertyAccessor
Actually set a property value.

Specified by:
setPropertyValue in interface PropertyAccessor
Specified by:
setPropertyValue in class AbstractPropertyAccessor
Parameters:
propertyName - name of the property to set value of
value - the new value
Throws:
InvalidPropertyException - if there is no such property or if the property isn't writable
PropertyAccessException - if the property was valid but the accessor method failed or a type mismatch occured
BeansException

setPropertyValue

public void setPropertyValue(PropertyValue pv)
                      throws BeansException
Description copied from interface: PropertyAccessor
Set the specified value as current property value.

Specified by:
setPropertyValue in interface PropertyAccessor
Overrides:
setPropertyValue in class AbstractPropertyAccessor
Parameters:
pv - an object containing the new property value
Throws:
InvalidPropertyException - if there is no such property or if the property isn't writable
PropertyAccessException - if the property was valid but the accessor method failed or a type mismatch occured
BeansException

toString

public String toString()
Overrides:
toString in class Object