org.apache.commons.beanutils
public class LazyDynaBean extends Object implements DynaBean, Serializable
DynaBean which automatically adds properties to the DynaClass
and provides Lazy List and Lazy Map features.
DynaBeans deal with three types of properties - simple, indexed and mapped and
have the following get()
and set()
methods for
each of these types:
get(name)
and
set(name, value)
get(name, index)
and
set(name, index, value)
get(name, key)
and
set(name, key, value)
Getting Property Values
Calling any of the get()
methods, for a property which
doesn't exist, returns null
in this implementation.
Setting Simple Properties
The LazyDynaBean
will automatically add a property to the DynaClass
if it doesn't exist when the set(name, value)
method is called.
DynaBean myBean = new LazyDynaBean();
myBean.set("myProperty", "myValue");
Setting Indexed Properties
If the property doesn't exist, the LazyDynaBean
will automatically add
a property with an ArrayList
type to the DynaClass
when
the set(name, index, value)
method is called.
It will also instantiate a new ArrayList
and automatically grow
the List
so that it is big enough to accomodate the index being set.
ArrayList
is the default indexed property that LazyDynaBean uses but
this can be easily changed by overriding the defaultIndexedProperty(name)
method.
DynaBean myBean = new LazyDynaBean();
myBean.set("myIndexedProperty", 0, "myValue1");
myBean.set("myIndexedProperty", 1, "myValue2");
If the indexed property does exist in the DynaClass
but is set to
null
in the LazyDynaBean
, then it will instantiate a
new List
or Array
as specified by the property's type
in the DynaClass
and automatically grow the List
or Array
so that it is big enough to accomodate the index being set.
DynaBean myBean = new LazyDynaBean();
MutableDynaClass myClass = (MutableDynaClass)myBean.getDynaClass();
myClass.add("myIndexedProperty", int[].class);
myBean.set("myIndexedProperty", 0, new Integer(10));
myBean.set("myIndexedProperty", 1, new Integer(20));
Setting Mapped Properties
If the property doesn't exist, the LazyDynaBean
will automatically add
a property with a HashMap
type to the DynaClass
and
instantiate a new HashMap
in the DynaBean when the
set(name, key, value)
method is called. HashMap
is the default
mapped property that LazyDynaBean uses but this can be easily changed by overriding
the defaultMappedProperty(name)
method.
DynaBean myBean = new LazyDynaBean();
myBean.set("myMappedProperty", "myKey", "myValue");
If the mapped property does exist in the DynaClass
but is set to
null
in the LazyDynaBean
, then it will instantiate a
new Map
as specified by the property's type in the DynaClass
.
DynaBean myBean = new LazyDynaBean();
MutableDynaClass myClass = (MutableDynaClass)myBean.getDynaClass();
myClass.add("myMappedProperty", TreeMap.class);
myBean.set("myMappedProperty", "myKey", "myValue");
Restricted DynaClass
MutableDynaClass
have a facility to restrict the DynaClass
so that its properties cannot be modified. If the MutableDynaClass
is
restricted then calling any of the set()
methods for a property which
doesn't exist will result in a IllegalArgumentException
being thrown.
See Also: LazyDynaClass
Field Summary | |
---|---|
protected static BigDecimal | BigDecimal_ZERO BigDecimal Zero |
protected static BigInteger | BigInteger_ZERO BigInteger Zero |
protected static Byte | Byte_ZERO Byte Zero |
protected static Character | Character_SPACE Character Space |
protected MutableDynaClass | dynaClass
The MutableDynaClass "base class" that this DynaBean
is associated with. |
protected static Double | Double_ZERO Double Zero |
protected static Float | Float_ZERO Float Zero |
protected static Integer | Integer_ZERO Integer Zero |
protected static Long | Long_ZERO Long Zero |
protected static Short | Short_ZERO Short Zero |
protected Map | values
The MutableDynaClass "base class" that this DynaBean
is associated with. |
Constructor Summary | |
---|---|
LazyDynaBean()
Construct a new LazyDynaBean with a LazyDynaClass instance. | |
LazyDynaBean(String name)
Construct a new LazyDynaBean with a LazyDynaClass instance.
| |
LazyDynaBean(DynaClass dynaClass)
Construct a new DynaBean associated with the specified
DynaClass instance - if its not a MutableDynaClass
then a new LazyDynaClass is created and the properties copied.
|
Method Summary | |
---|---|
boolean | contains(String name, String key)
Does the specified mapped property contain a value for the specified
key value?
|
protected Object | createDynaBeanProperty(String name, Class type)
Create a new Instance of a 'DynaBean' Property. |
protected Object | createIndexedProperty(String name, Class type)
Create a new Instance of an 'Indexed' Property |
protected Object | createMappedProperty(String name, Class type)
Create a new Instance of a 'Mapped' Property |
protected Object | createNumberProperty(String name, Class type)
Create a new Instance of a java.lang.Number Property. |
protected Object | createOtherProperty(String name, Class type)
Create a new Instance of other Property types |
protected Object | createPrimitiveProperty(String name, Class type)
Create a new Instance of a 'Primitive' Property. |
protected Object | createProperty(String name, Class type)
Create a new Instance of a Property |
protected Object | defaultIndexedProperty(String name) Creates a new This method shouls be overriden if an alternative |
protected Map | defaultMappedProperty(String name) Creates a new This method can be overriden if an alternative |
Object | get(String name) Return the value of a simple property with the specified name. N.B. Returns |
Object | get(String name, int index) Return the value of an indexed property with the specified name. N.B. Returns |
Object | get(String name, String key) Return the value of a mapped property with the specified name. N.B. Returns |
DynaClass | getDynaClass()
Return the DynaClass instance that describes the set of
properties available for this DynaBean.
|
Map | getMap()
Return a Map representation of this DynaBean.
|
protected Object | growIndexedProperty(String name, Object indexedProperty, int index)
Grow the size of an indexed property |
protected boolean | isAssignable(Class dest, Class source)
Is an object of the source class assignable to the destination class?
|
protected boolean | isDynaProperty(String name)
Indicates if there is a property with the specified name. |
protected Map | newMap() Creates a new instance of the |
void | remove(String name, String key)
Remove any existing value for the specified key on the
specified mapped property.
|
void | set(String name, Object value)
Set the value of a simple property with the specified name.
|
void | set(String name, int index, Object value)
Set the value of an indexed property with the specified name.
|
void | set(String name, String key, Object value)
Set the value of a mapped property with the specified name.
|
int | size(String name) Return the size of an indexed or mapped property. |
MutableDynaClass
"base class" that this DynaBean
is associated with.MutableDynaClass
"base class" that this DynaBean
is associated with.LazyDynaBean
with a LazyDynaClass
instance.LazyDynaBean
with a LazyDynaClass
instance.
Parameters: name Name of this DynaBean class
DynaBean
associated with the specified
DynaClass
instance - if its not a MutableDynaClass
then a new LazyDynaClass
is created and the properties copied.
Parameters: dynaClass The DynaClass we are associated with
Parameters: name Name of the property to check key Name of the key to check
Returns: true
if the mapped property contains a value for
the specified key, otherwise
false
Throws: IllegalArgumentException if no property name is specified
Parameters: name The name of the property type The class of the property
Returns: The new value
Parameters: name The name of the property type The class of the property
Returns: The new value
Parameters: name The name of the property type The class of the property
Returns: The new value
java.lang.Number
Property.Parameters: name The name of the property type The class of the property
Returns: The new value
Parameters: name The name of the property type The class of the property
Returns: The new value
Parameters: name The name of the property type The class of the property
Returns: The new value
Parameters: name The name of the property type The class of the property
Returns: The new value
Creates a new ArrayList
for an 'indexed' property
which doesn't exist.
This method shouls be overriden if an alternative List
or Array
implementation is required for 'indexed' properties.
Parameters: name Name of the 'indexed property.
Returns: The default value for an indexed property (java.util.ArrayList)
Creates a new HashMap
for a 'mapped' property
which doesn't exist.
This method can be overriden if an alternative Map
implementation is required for 'mapped' properties.
Parameters: name Name of the 'mapped property.
Returns: The default value for a mapped property (java.util.HashMap)
Return the value of a simple property with the specified name.
N.B. Returns null
if there is no property
of the specified name.
Parameters: name Name of the property whose value is to be retrieved.
Returns: The property's value
Throws: IllegalArgumentException if no property name is specified
Return the value of an indexed property with the specified name.
N.B. Returns null
if there is no 'indexed'
property of the specified name.
Parameters: name Name of the property whose value is to be retrieved index Index of the value to be retrieved
Returns: The indexed property's value
Throws: IllegalArgumentException if the specified property exists, but is not indexed IndexOutOfBoundsException if the specified index is outside the range of the underlying property
Return the value of a mapped property with the specified name.
N.B. Returns null
if there is no 'mapped'
property of the specified name.
Parameters: name Name of the property whose value is to be retrieved key Key of the value to be retrieved
Returns: The mapped property's value
Throws: IllegalArgumentException if the specified property exists, but is not mapped
DynaClass
instance that describes the set of
properties available for this DynaBean.
Returns: The associated DynaClass
fooProperty
:
${myDynaBean.map.fooProperty}
Returns: a Map representation of this DynaBean
Parameters: name The name of the property indexedProperty The current property value index The indexed value to grow the property to (i.e. one less than the required size)
Returns: The new property value (grown to the appropriate size)
Parameters: dest Destination class source Source class
Returns: true
if the source class is assignable to the
destination class, otherwise
false
Parameters: name The name of the property to check
Returns: true
if there is a property of the
specified name, otherwise
false
Creates a new instance of the Map
.
Returns: a new Map instance
Parameters: name Name of the property for which a value is to be removed key Key of the value to be removed
Throws: IllegalArgumentException if there is no property of the specified name
Parameters: name Name of the property whose value is to be set value Value to which this property is to be set
Throws: IllegalArgumentException if this is not an existing property name for our DynaClass and the MutableDynaClass is restricted ConversionException if the specified value cannot be converted to the type required for this property NullPointerException if an attempt is made to set a primitive property to null
Parameters: name Name of the property whose value is to be set index Index of the property to be set value Value to which this property is to be set
Throws: ConversionException if the specified value cannot be converted to the type required for this property IllegalArgumentException if there is no property of the specified name IllegalArgumentException if the specified property exists, but is not indexed IndexOutOfBoundsException if the specified index is outside the range of the underlying property
Parameters: name Name of the property whose value is to be set key Key of the property to be set value Value to which this property is to be set
Throws: ConversionException if the specified value cannot be converted to the type required for this property IllegalArgumentException if there is no property of the specified name IllegalArgumentException if the specified property exists, but is not mapped
Return the size of an indexed or mapped property.
Parameters: name Name of the property
Returns: The indexed or mapped property size
Throws: IllegalArgumentException if no property name is specified