| java.lang.Object
 org.apache.commons.beanutils.BasicDynaClass
org.apache.commons.beanutils.LazyDynaClass
| LazyDynaClass | | public class LazyDynaClass extends BasicDynaClass implements MutableDynaClass(Code) | | DynaClass which implements the MutableDynaClass interface.
A MutableDynaClass is a specialized extension to DynaClass
that allows properties to be added or removed dynamically.
This implementation has one slightly unusual default behaviour - calling
the getDynaProperty(name) method for a property which doesn't
exist returns a DynaProperty rather than null. The
reason for this is that BeanUtils calls this method to check if
a property exists before trying to set the value. This would defeat the object
of the LazyDynaBean which automatically adds missing properties
when any of its set() methods are called. For this reason the
isDynaProperty(name) method has been added to this implementation
in order to determine if a property actually exists. If the more normal
behaviour of returning null is required, then this can be achieved
by calling the setReturnNull(true).
The add(name, type, readable, writable) method is not implemented
and always throws an UnsupportedOperationException. I believe
this attributes need to be added to the DynaProperty class
in order to control read/write facilities.
See Also: LazyDynaBean
author:
Niall Pemberton |
| Field Summary | |
| protected boolean | restricted
Controls whether changes to this DynaClass's properties are allowed. | | protected boolean | returnNull
Controls whether the getDynaProperty() method returns
null if a property doesn't exist - or creates a new one.
Default is false. |
| Method Summary | |
| public void | add(String name)
Add a new dynamic property with no restrictions on data type,
readability, or writeability. | | public void | add(String name, Class type)
Add a new dynamic property with the specified data type, but with
no restrictions on readability or writeability. | | public void | add(String name, Class type, boolean readable, boolean writeable)
| | protected void | add(DynaProperty property)
Add a new dynamic property. | | public DynaProperty | getDynaProperty(String name)
Return a property descriptor for the specified property.
If the property is not found and the returnNull indicator is
true, this method always returns null.
If the property is not found and the returnNull indicator is
false a new property descriptor is created and returned (although
its not actually added to the DynaClass's properties). | | public boolean | isDynaProperty(String name)
| | public boolean | isRestricted()
| | public boolean | isReturnNull()
Should this DynaClass return a null from
the getDynaProperty(name) method if the property
doesn't exist. | | public void | remove(String name)
Remove the specified dynamic property, and any associated data type,
readability, and writeability, from this dynamic class. | | public void | setRestricted(boolean restricted)
| | public void | setReturnNull(boolean returnNull)
Set whether this DynaClass should return a null from
the getDynaProperty(name) method if the property
doesn't exist. |
| restricted | | protected boolean restricted(Code) | | Controls whether changes to this DynaClass's properties are allowed.
|
| returnNull | | protected boolean returnNull(Code) | | Controls whether the getDynaProperty() method returns
null if a property doesn't exist - or creates a new one.
Default is false.
|
| LazyDynaClass | | public LazyDynaClass()(Code) | | Construct a new LazyDynaClass with default parameters.
|
| LazyDynaClass | | public LazyDynaClass(String name)(Code) | | Construct a new LazyDynaClass with the specified name.
Parameters:
name - Name of this DynaBean class |
| LazyDynaClass | | public LazyDynaClass(String name, Class dynaBeanClass)(Code) | | Construct a new LazyDynaClass with the specified name and DynaBean class.
Parameters:
name - Name of this DynaBean class
Parameters:
dynaBeanClass - The implementation class for new instances |
| LazyDynaClass | | public LazyDynaClass(String name, DynaProperty[] properties)(Code) | | Construct a new LazyDynaClass with the specified name and properties.
Parameters:
name - Name of this DynaBean class
Parameters:
properties - Property descriptors for the supported properties |
| LazyDynaClass | | public LazyDynaClass(String name, Class dynaBeanClass, DynaProperty properties)(Code) | | Construct a new LazyDynaClass with the specified name, DynaBean class and properties.
Parameters:
name - Name of this DynaBean class
Parameters:
dynaBeanClass - The implementation class for new intances
Parameters:
properties - Property descriptors for the supported properties |
| add | | public void add(String name)(Code) | | Add a new dynamic property with no restrictions on data type,
readability, or writeability.
Parameters:
name - Name of the new dynamic property
exception:
IllegalArgumentException - if name is null
exception:
IllegalStateException - if this DynaClass is currentlyrestricted, so no new properties can be added |
| add | | public void add(String name, Class type)(Code) | | Add a new dynamic property with the specified data type, but with
no restrictions on readability or writeability.
Parameters:
name - Name of the new dynamic property
Parameters:
type - Data type of the new dynamic property (null for norestrictions)
exception:
IllegalArgumentException - if name is null
exception:
IllegalStateException - if this DynaClass is currentlyrestricted, so no new properties can be added |
| add | | public void add(String name, Class type, boolean readable, boolean writeable)(Code) | | Add a new dynamic property with the specified data type, readability,
and writeability.
N.B.Support for readable/writeable properties has not been implemented
and this method always throws a UnsupportedOperationException.
I'm not sure the intention of the original authors for this method, but it seems to
me that readable/writable should be attributes of the DynaProperty class
(which they are not) and is the reason this method has not been implemented.
Parameters:
name - Name of the new dynamic property
Parameters:
type - Data type of the new dynamic property (null for norestrictions)
Parameters:
readable - Set to true if this property valueshould be readable
Parameters:
writeable - Set to true if this property valueshould be writeable
exception:
UnsupportedOperationException - anytime this method is called |
| getDynaProperty | | public DynaProperty getDynaProperty(String name)(Code) | | Return a property descriptor for the specified property.
If the property is not found and the returnNull indicator is
true, this method always returns null.
If the property is not found and the returnNull indicator is
false a new property descriptor is created and returned (although
its not actually added to the DynaClass's properties). This is the default
beahviour.
The reason for not returning a null property descriptor is that
BeanUtils uses this method to check if a property exists
before trying to set it - since these Lazy implementations automatically
add any new properties when they are set, returning null from
this method would defeat their purpose.
Parameters:
name - Name of the dynamic property for which a descriptoris requested The dyna property for the specified name
exception:
IllegalArgumentException - if no property name is specified |
| isDynaProperty | | public boolean isDynaProperty(String name)(Code) | | Indicate whether a property actually exists.
N.B. Using getDynaProperty(name) == null
doesn't work in this implementation because that method might
return a DynaProperty if it doesn't exist (depending on the
returnNull indicator).
Parameters:
name - The name of the property to check true if there is a property of thespecified name, otherwise false
exception:
IllegalArgumentException - if no property name is specified |
| isRestricted | | public boolean isRestricted()(Code) | | Is this DynaClass currently restricted.
If restricted, no changes to the existing registration of
property names, data types, readability, or writeability are allowed.
true if this MutableDynaClass cannot be changedotherwise false |
| isReturnNull | | public boolean isReturnNull()(Code) | | Should this DynaClass return a null from
the getDynaProperty(name) method if the property
doesn't exist.
true if a null DynaPropertyshould be returned if the property doesn't exist, otherwisefalse if a new DynaProperty should be created. |
| remove | | public void remove(String name)(Code) | | Remove the specified dynamic property, and any associated data type,
readability, and writeability, from this dynamic class.
NOTE - This does NOT cause any
corresponding property values to be removed from DynaBean instances
associated with this DynaClass.
Parameters:
name - Name of the dynamic property to remove
exception:
IllegalArgumentException - if name is null
exception:
IllegalStateException - if this DynaClass is currentlyrestricted, so no properties can be removed |
| setRestricted | | public void setRestricted(boolean restricted)(Code) | | Set whether this DynaClass is currently restricted.
If restricted, no changes to the existing registration of
property names, data types, readability, or writeability are allowed.
Parameters:
restricted - true if this MutableDynaClass cannotbe changed otherwise false |
| setReturnNull | | public void setReturnNull(boolean returnNull)(Code) | | Set whether this DynaClass should return a null from
the getDynaProperty(name) method if the property
doesn't exist.
Parameters:
returnNull - true if a null DynaPropertyshould be returned if the property doesn't exist, otherwisefalse if a new DynaProperty should be created. |
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