AccessibleObject
open class AccessibleObject : AnnotatedElement
Known Direct Subclasses
Executable |
A shared superclass for the common functionality of Method and Constructor .
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Field |
A Field provides information about, and dynamic access to, a single field of a class or an interface.
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Known Indirect Subclasses
Constructor |
Constructor provides information about, and access to, a single constructor for a class.
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Method |
A Method provides information about, and access to, a single method on a class or interface.
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The AccessibleObject class is the base class for Field, Method and Constructor objects. It provides the ability to flag a reflected object as suppressing default Java language access control checks when it is used. The access checks--for public, default (package) access, protected, and private members--are performed when Fields, Methods or Constructors are used to set or get fields, to invoke methods, or to create and initialize new instances of classes, respectively.
Setting the accessible
flag in a reflected object permits sophisticated applications with sufficient privilege, such as Java Object Serialization or other persistence mechanisms, to manipulate objects in a manner that would normally be prohibited.
By default, a reflected object is not accessible.
Summary
Protected constructors |
Constructor: only used by the Java Virtual Machine.
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Public methods |
open T? |
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open Array<Annotation!> |
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open Array<T>! |
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open T? |
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open Array<Annotation!> |
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open Array<T>! |
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open Boolean |
Get the value of the accessible flag for this object.
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open Boolean |
Returns true if an annotation for the specified type is present on this element, else false.
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open Unit |
Set the accessible flag for this object to the indicated boolean value.
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open static Unit |
Convenience method to set the accessible flag for an array of objects with a single security check (for efficiency).
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Protected constructors
AccessibleObject
protected AccessibleObject()
Constructor: only used by the Java Virtual Machine.
Public methods
getAnnotation
open fun <T : Annotation!> getAnnotation(annotationClass: Class<T>): T?
Parameters |
<T> |
the type of the annotation to query for and return if present |
annotationClass |
Class<T>: the Class object corresponding to the annotation type |
Return |
T? |
this element's annotation for the specified annotation type if present on this element, else null |
Exceptions |
java.lang.NullPointerException |
if the given annotation class is null |
getAnnotationsByType
open fun <T : Annotation!> getAnnotationsByType(annotationClass: Class<T>): Array<T>!
Parameters |
<T> |
the type of the annotation to query for and return if present |
annotationClass |
Class<T>: the Class object corresponding to the annotation type |
Return |
Array<T>! |
all this element's annotations for the specified annotation type if associated with this element, else an array of length zero |
Exceptions |
java.lang.NullPointerException |
if the given annotation class is null |
getDeclaredAnnotation
open fun <T : Annotation!> getDeclaredAnnotation(annotationClass: Class<T>): T?
Parameters |
<T> |
the type of the annotation to query for and return if directly present |
annotationClass |
Class<T>: the Class object corresponding to the annotation type |
Return |
T? |
this element's annotation for the specified annotation type if directly present on this element, else null |
Exceptions |
java.lang.NullPointerException |
if the given annotation class is null |
getDeclaredAnnotations
open fun getDeclaredAnnotations(): Array<Annotation!>
getDeclaredAnnotationsByType
open fun <T : Annotation!> getDeclaredAnnotationsByType(annotationClass: Class<T>): Array<T>!
Parameters |
<T> |
the type of the annotation to query for and return if directly or indirectly present |
annotationClass |
Class<T>: the Class object corresponding to the annotation type |
Return |
Array<T>! |
all this element's annotations for the specified annotation type if directly or indirectly present on this element, else an array of length zero |
Exceptions |
java.lang.NullPointerException |
if the given annotation class is null |
isAccessible
open fun isAccessible(): Boolean
Get the value of the accessible
flag for this object.
Return |
Boolean |
the value of the object's accessible flag |
isAnnotationPresent
open fun isAnnotationPresent(annotationClass: Class<out Annotation!>): Boolean
Returns true if an annotation for the specified type is present on this element, else false. This method is designed primarily for convenient access to marker annotations.
The truth value returned by this method is equivalent to: getAnnotation(annotationClass) != null
The body of the default method is specified to be the code above.
Parameters |
annotationClass |
Class<out Annotation!>: the Class object corresponding to the annotation type |
Return |
Boolean |
true if an annotation for the specified annotation type is present on this element, else false |
Exceptions |
java.lang.NullPointerException |
if the given annotation class is null |
setAccessible
open fun setAccessible(flag: Boolean): Unit
Set the accessible
flag for this object to the indicated boolean value. A value of true
indicates that the reflected object should suppress Java language access checking when it is used. A value of false
indicates that the reflected object should enforce Java language access checks.
First, if there is a security manager, its checkPermission
method is called with a ReflectPermission("suppressAccessChecks")
permission.
A SecurityException
is raised if flag
is true
but accessibility of this object may not be changed (for example, if this element object is a Constructor
object for the class java.lang.Class
).
A SecurityException
is raised if this object is a object for the class java.lang.Class
, and flag
is true.
Parameters |
flag |
Boolean: the new value for the accessible flag |
Exceptions |
java.lang.SecurityException |
if the request is denied. |
setAccessible
open static fun setAccessible(
array: Array<AccessibleObject!>!,
flag: Boolean
): Unit
Convenience method to set the accessible
flag for an array of objects with a single security check (for efficiency).
First, if there is a security manager, its checkPermission
method is called with a ReflectPermission("suppressAccessChecks")
permission.
A SecurityException
is raised if flag
is true
but accessibility of any of the elements of the input array
may not be changed (for example, if the element object is a Constructor
object for the class ). In the event of such a SecurityException, the accessibility of objects is set to flag
for array elements upto (and excluding) the element for which the exception occurred; the accessibility of elements beyond (and including) the element for which the exception occurred is unchanged.
Parameters |
array |
Array<AccessibleObject!>!: the array of AccessibleObjects |
flag |
Boolean: the new value for the accessible flag in each object |
Exceptions |
java.lang.SecurityException |
if the request is denied. |