The Introspector
is a utility for developers to figure out
which properties, events, and methods a JavaBean supports.
The Introspector
class walks over the class/superclass chain
of the target bean class. At each level it checks if there is a matching
BeanInfo
class which provides explicit information about the
bean, and if so uses that explicit information. Otherwise it uses the low
level reflection APIs to study the target class and uses design patterns to
analyze its behaviour and then proceeds to continue the introspection with
its baseclass.
To look for the explicit information of a bean:
- The
Introspector
appends "BeanInfo" to the qualified name of the bean class, try to use the new class as the "BeanInfo" class. If the "BeanInfo" class exsits and returns non-null value when queried for explicit information, use the explicit information - If the first step fails, the
Introspector
will extract a simple class name of the bean class by removing the package name from the qualified name of the bean class, append "BeanInfo" to it. And look for the simple class name in the packages defined in the "BeanInfo" search path (The default "BeanInfo" search path issun.beans.infos
). If it finds a "BeanInfo" class and the "BeanInfo" class returns non-null value when queried for explicit information, use the explicit information
Constant Summary
int | IGNORE_ALL_BEANINFO | Constant values to indicate that the Introspector will
ignore all BeanInfo class. |
int | IGNORE_IMMEDIATE_BEANINFO | Constant values to indicate that the Introspector will
ignore the BeanInfo class of the current bean class. |
int | USE_ALL_BEANINFO | Constant values to indicate that the Introspector will use
all BeanInfo class which have been found. |
Public Method Summary
static String |
decapitalize(String name)
Decapitalizes a given string according to the rule:
|
static void |
flushCaches()
Flushes all
BeanInfo caches. |
static void | |
static BeanInfo |
getBeanInfo(Class<?> beanClass, Class<?> stopClass)
Gets the
BeanInfo object which contains the information of
the properties, events and methods of the specified bean class. |
static BeanInfo |
getBeanInfo(Class<?> beanClass, int flags)
Gets the
BeanInfo object which contains the information of
the properties, events and methods of the specified bean class. |
static BeanInfo |
getBeanInfo(Class<?> beanClass)
Gets the
BeanInfo object which contains the information of
the properties, events and methods of the specified bean class. |
static String[] |
getBeanInfoSearchPath()
Gets an array of search packages.
|
static void |
Inherited Method Summary
Constants
public static final int IGNORE_ALL_BEANINFO
Constant values to indicate that the Introspector
will
ignore all BeanInfo
class.
public static final int IGNORE_IMMEDIATE_BEANINFO
Constant values to indicate that the Introspector
will
ignore the BeanInfo
class of the current bean class.
public static final int USE_ALL_BEANINFO
Constant values to indicate that the Introspector
will use
all BeanInfo
class which have been found. This is the default one.
Public Methods
public static String decapitalize (String name)
Decapitalizes a given string according to the rule:
- If the first or only character is Upper Case, it is made Lower Case
- UNLESS the second character is also Upper Case, when the String is
returned unchanged
Parameters
name | - the String to decapitalize |
---|
Returns
- the decapitalized version of the String
public static void flushCaches ()
Flushes all BeanInfo
caches.
public static void flushFromCaches (Class<?> clazz)
Flushes the BeanInfo
caches of the specified bean class
Parameters
clazz | the specified bean class |
---|
public static BeanInfo getBeanInfo (Class<?> beanClass, Class<?> stopClass)
Gets the BeanInfo
object which contains the information of
the properties, events and methods of the specified bean class. It will
not introspect the "stopclass" and its super class.
The Introspector
will cache the BeanInfo
object. Subsequent calls to this method will be answered with the cached
data.
Parameters
beanClass | the specified beanClass. |
---|---|
stopClass | the sopt class which should be super class of the bean class. May be null. |
Returns
- the
BeanInfo
of the bean class.
Throws
IntrospectionException |
---|
public static BeanInfo getBeanInfo (Class<?> beanClass, int flags)
Gets the BeanInfo
object which contains the information of
the properties, events and methods of the specified bean class.
- If
flag==IGNORE_ALL_BEANINFO
, theIntrospector
will ignore allBeanInfo
class. - If
flag==IGNORE_IMMEDIATE_BEANINFO
, theIntrospector
will ignore theBeanInfo
class of the current bean class. - If
flag==USE_ALL_BEANINFO
, theIntrospector
will use allBeanInfo
class which have been found.
The Introspector
will cache the BeanInfo
object. Subsequent calls to this method will be answered with the cached
data.
Parameters
beanClass | the specified bean class. |
---|---|
flags | the flag to control the usage of the explicit
BeanInfo class. |
Returns
- the
BeanInfo
of the bean class.
Throws
IntrospectionException |
---|
public static BeanInfo getBeanInfo (Class<?> beanClass)
Gets the BeanInfo
object which contains the information of
the properties, events and methods of the specified bean class.
The Introspector
will cache the BeanInfo
object. Subsequent calls to this method will be answered with the cached
data.
Parameters
beanClass | the specified bean class. |
---|
Returns
- the
BeanInfo
of the bean class.
Throws
IntrospectionException |
---|
public static String[] getBeanInfoSearchPath ()
Gets an array of search packages.
Returns
- an array of search packages.
public static void setBeanInfoSearchPath (String[] path)
Sets the search packages.
Parameters
path | the new search packages to be set. |
---|