JavaBean property population methods.
This class provides implementations for the utility methods in
BeanUtils
.
Different instances can be used to isolate caches between classloaders
and to vary the value converters registered.
cloneBean
public Object cloneBean(Object bean)
throws IllegalAccessException,
InstantiationException,
InvocationTargetException,
NoSuchMethodException
Clone a bean based on the available property getters and setters,
even if the bean class itself does not implement Cloneable.
Note: this method creates a
shallow clone.
In other words, any objects referred to by the bean are shared with the clone
rather than being cloned in turn.
copyProperties
public void copyProperties(Object dest,
Object orig)
throws IllegalAccessException,
InvocationTargetException
Copy property values from the origin bean to the destination bean
for all cases where the property names are the same. For each
property, a conversion is attempted as necessary. All combinations of
standard JavaBeans and DynaBeans as origin and destination are
supported. Properties that exist in the origin bean, but do not exist
in the destination bean (or are read-only in the destination bean) are
silently ignored.
If the origin "bean" is actually a
Map
, it is assumed
to contain String-valued
simple property names as the keys, pointing at
the corresponding property values that will be converted (if necessary)
and set in the destination bean.
Note that this method
is intended to perform a "shallow copy" of the properties and so complex
properties (for example, nested ones) will not be copied.
This method differs from
populate()
, which
was primarily designed for populating JavaBeans from the map of request
parameters retrieved on an HTTP request, is that no scalar->indexed
or indexed->scalar manipulations are performed. If the origin property
is indexed, the destination property must be also.
If you know that no type conversions are required, the
copyProperties()
method in
PropertyUtils
will
execute faster than this method.
FIXME - Indexed and mapped properties that do not
have getter and setter methods for the underlying array or Map are not
copied by this method.
dest
- Destination bean whose properties are modifiedorig
- Origin bean whose properties are retrieved
copyProperty
public void copyProperty(Object bean,
String name,
Object value)
throws IllegalAccessException,
InvocationTargetException
Copy the specified property value to the specified destination bean,
performing any type conversion that is required. If the specified
bean does not have a property of the specified name, or the property
is read only on the destination bean, return without
doing anything. If you have custom destination property types, register
Converter
s for them by calling the
register()
method of
ConvertUtils
.
IMPLEMENTATION RESTRICTIONS:
- Does not support destination properties that are indexed,
but only an indexed setter (as opposed to an array setter)
is available.
- Does not support destination properties that are mapped,
but only a keyed setter (as opposed to a Map setter)
is available.
- The desired property type of a mapped setter cannot be
determined (since Maps support any data type), so no conversion
will be performed.
bean
- Bean on which setting is to be performedname
- Property name (can be nested/indexed/mapped/combo)value
- Value to be set
describe
public Map describe(Object bean)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the entire set of properties for which the specified bean
provides a read method. This map contains the to
String
converted property values for all properties for which a read method
is provided (i.e. where the getReadMethod() returns non-null).
This map can be fed back to a call to
BeanUtils.populate()
to reconsitute the same set of
properties, modulo differences for read-only and write-only
properties, but only if there are no indexed properties.
bean
- Bean whose properties are to be extracted
findLastNestedIndex
private int findLastNestedIndex(String expression)
getArrayProperty
public String[] getArrayProperty(Object bean,
String name)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified array property of the specified
bean, as a String array.
bean
- Bean whose property is to be extractedname
- Name of the property to be extracted
getConvertUtils
public ConvertUtilsBean getConvertUtils()
Gets the ConvertUtilsBean
instance used to perform the conversions.
getIndexedProperty
public String getIndexedProperty(Object bean,
String name)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified indexed property of the specified
bean, as a String. The zero-relative index of the
required value must be included (in square brackets) as a suffix to
the property name, or IllegalArgumentException
will be
thrown.
bean
- Bean whose property is to be extractedname
- propertyname[index]
of the property value
to be extracted
getIndexedProperty
public String getIndexedProperty(Object bean,
String name,
int index)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified indexed property of the specified
bean, as a String. The index is specified as a method parameter and
must *not* be included in the property name expression
bean
- Bean whose property is to be extractedname
- Simple property name of the property value to be extractedindex
- Index of the property value to be extracted
getInstance
public static BeanUtilsBean getInstance()
Gets the instance which provides the functionality for
BeanUtils
.
This is a pseudo-singleton - an single instance is provided per (thread) context classloader.
This mechanism provides isolation for web apps deployed in the same container.
getMappedProperty
public String getMappedProperty(Object bean,
String name)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified indexed property of the specified
bean, as a String. The String-valued key of the required value
must be included (in parentheses) as a suffix to
the property name, or IllegalArgumentException
will be
thrown.
bean
- Bean whose property is to be extractedname
- propertyname(index)
of the property value
to be extracted
getMappedProperty
public String getMappedProperty(Object bean,
String name,
String key)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified mapped property of the specified
bean, as a String. The key is specified as a method parameter and
must *not* be included in the property name expression
bean
- Bean whose property is to be extractedname
- Simple property name of the property value to be extractedkey
- Lookup key of the property value to be extracted
getNestedProperty
public String getNestedProperty(Object bean,
String name)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the (possibly nested) property of the specified
name, for the specified bean, as a String.
bean
- Bean whose property is to be extractedname
- Possibly nested name of the property to be extracted
getProperty
public String getProperty(Object bean,
String name)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified property of the specified bean,
no matter which property reference format is used, as a String.
bean
- Bean whose property is to be extractedname
- Possibly indexed and/or nested name of the property
to be extracted
getPropertyUtils
public PropertyUtilsBean getPropertyUtils()
Gets the PropertyUtilsBean
instance used to access properties.
getSimpleProperty
public String getSimpleProperty(Object bean,
String name)
throws IllegalAccessException,
InvocationTargetException,
NoSuchMethodException
Return the value of the specified simple property of the specified
bean, converted to a String.
bean
- Bean whose property is to be extractedname
- Name of the property to be extracted
populate
public void populate(Object bean,
Map properties)
throws IllegalAccessException,
InvocationTargetException
Populate the JavaBeans properties of the specified bean, based on
the specified name/value pairs. This method uses Java reflection APIs
to identify corresponding "property setter" method names, and deals
with setter arguments of type
String
,
boolean
,
int
,
long
,
float
, and
double
. In addition, array setters for these types (or the
corresponding primitive types) can also be identified.
The particular setter method to be called for each property is
determined using the usual JavaBeans introspection mechanisms. Thus,
you may identify custom setter methods using a BeanInfo class that is
associated with the class of the bean itself. If no such BeanInfo
class is available, the standard method name conversion ("set" plus
the capitalized name of the property in question) is used.
NOTE: It is contrary to the JavaBeans Specification
to have more than one setter method (with different argument
signatures) for the same property.
WARNING - The logic of this method is customized
for extracting String-based request parameters from an HTTP request.
It is probably not what you want for general property copying with
type conversion. For that purpose, check out the
copyProperties()
method instead.
bean
- JavaBean whose properties are being populatedproperties
- Map keyed by property name, with the
corresponding (String or String[]) value(s) to be set
setInstance
public static void setInstance(BeanUtilsBean newInstance)
Sets the instance which provides the functionality for
BeanUtils
.
This is a pseudo-singleton - an single instance is provided per (thread) context classloader.
This mechanism provides isolation for web apps deployed in the same container.
setProperty
public void setProperty(Object bean,
String name,
Object value)
throws IllegalAccessException,
InvocationTargetException
Set the specified property value, performing type conversions as
required to conform to the type of the destination property.
If the property is read only then the method returns
without throwing an exception.
If
null
is passed into a property expecting a primitive value,
then this will be converted as if it were a
null
string.
WARNING - The logic of this method is customized
to meet the needs of
populate()
, and is probably not what
you want for general property copying with type conversion. For that
purpose, check out the
copyProperty()
method instead.
WARNING - PLEASE do not modify the behavior of this
method without consulting with the Struts developer community. There
are some subtleties to its functionality that are not documented in the
Javadoc description above, yet are vital to the way that Struts utilizes
this method.
bean
- Bean on which setting is to be performedname
- Property name (can be nested/indexed/mapped/combo)value
- Value to be set