AccessibleObject (Java Platform SE 8 ) (original) (raw)

java.lang.Object
- java.lang.reflect.AccessibleObject
All Implemented Interfaces:
AnnotatedElement
Direct Known Subclasses:
Executable, Field

public class AccessibleObject
extends Object
implements AnnotatedElement
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.
Since:
1.2
See Also:
Field, Method, Constructor, ReflectPermission

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AccessibleObject()	Constructor: only used by the Java Virtual Machine.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods

Modifier and Type	Method	Description
<T extends Annotation>T	getAnnotation(Class annotationClass)	Returns this element's annotation for the specified type if such an annotation is present, else null.
Annotation[]	getAnnotations()	Returns annotations that are present on this element.
<T extends Annotation>T[]	getAnnotationsByType(Class annotationClass)	Returns annotations that are associated with this element.
<T extends Annotation>T	getDeclaredAnnotation(Class annotationClass)	Returns this element's annotation for the specified type if such an annotation is directly present, else null.
Annotation[]	getDeclaredAnnotations()	Returns annotations that are directly present on this element.
<T extends Annotation>T[]	getDeclaredAnnotationsByType(Class annotationClass)	Returns this element's annotation(s) for the specified type if such annotations are either directly present or_indirectly present_.
boolean	isAccessible()	Get the value of the accessible flag for this object.
boolean	isAnnotationPresent(Class<? extends Annotation> annotationClass)	Returns true if an annotation for the specified type is present on this element, else false.
static void	setAccessible(AccessibleObject[] array, boolean flag)	Convenience method to set the accessible flag for an array of objects with a single security check (for efficiency).
void	setAccessible(boolean flag)	Set the accessible flag for this object to the indicated boolean value.

   * ### Methods inherited from class java.lang.[Object](../../../java/lang/Object.html "class in java.lang")  
   `[clone](../../../java/lang/Object.html#clone--), [equals](../../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../../java/lang/Object.html#finalize--), [getClass](../../../java/lang/Object.html#getClass--), [hashCode](../../../java/lang/Object.html#hashCode--), [notify](../../../java/lang/Object.html#notify--), [notifyAll](../../../java/lang/Object.html#notifyAll--), [toString](../../../java/lang/Object.html#toString--), [wait](../../../java/lang/Object.html#wait--), [wait](../../../java/lang/Object.html#wait-long-), [wait](../../../java/lang/Object.html#wait-long-int-)`

Constructor Detail

 * #### AccessibleObject  
 protected AccessibleObject()  
 Constructor: only used by the Java Virtual Machine.

Method Detail

* #### setAccessible  
public static void setAccessible([AccessibleObject](../../../java/lang/reflect/AccessibleObject.html "class in java.lang.reflect")[] array,  
                                 boolean flag)  
                          throws [SecurityException](../../../java/lang/SecurityException.html "class in java.lang")  
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](../../../java/lang/reflect/Constructor.html "class in java.lang.reflect") object for the class [Class](../../../java/lang/Class.html "class in java.lang")). 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` \- the array of AccessibleObjects  
`flag` \- the new value for the `accessible` flag in each object  
Throws:  
`[SecurityException](../../../java/lang/SecurityException.html "class in java.lang")` \- if the request is denied.  
See Also:  
[SecurityManager.checkPermission(java.security.Permission)](../../../java/lang/SecurityManager.html#checkPermission-java.security.Permission-), [RuntimePermission](../../../java/lang/RuntimePermission.html "class in java.lang")  
* #### setAccessible  
public void setAccessible(boolean flag)  
                   throws [SecurityException](../../../java/lang/SecurityException.html "class in java.lang")  
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](../../../java/lang/reflect/Constructor.html "class in java.lang.reflect") object for the class [Class](../../../java/lang/Class.html "class in java.lang")).  
A `SecurityException` is raised if this object is a [Constructor](../../../java/lang/reflect/Constructor.html "class in java.lang.reflect") object for the class`java.lang.Class`, and `flag` is true.  
Parameters:  
`flag` \- the new value for the `accessible` flag  
Throws:  
`[SecurityException](../../../java/lang/SecurityException.html "class in java.lang")` \- if the request is denied.  
See Also:  
[SecurityManager.checkPermission(java.security.Permission)](../../../java/lang/SecurityManager.html#checkPermission-java.security.Permission-), [RuntimePermission](../../../java/lang/RuntimePermission.html "class in java.lang")  
* #### isAccessible  
public boolean isAccessible()  
Get the value of the `accessible` flag for this object.  
Returns:  
the value of the object's `accessible` flag  
* #### getAnnotation  
public <T extends [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")> T getAnnotation([Class](../../../java/lang/Class.html "class in java.lang")<T> annotationClass)  
Returns this element's annotation for the specified type if such an annotation is _present_, else null.  
Specified by:  
`[getAnnotation](../../../java/lang/reflect/AnnotatedElement.html#getAnnotation-java.lang.Class-)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Type Parameters:  
`T` \- the type of the annotation to query for and return if present  
Parameters:  
`annotationClass` \- the Class object corresponding to the annotation type  
Returns:  
this element's annotation for the specified annotation type if present on this element, else null  
Throws:  
`[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang")` \- if the given annotation class is null  
Since:  
1.5  
* #### isAnnotationPresent  
public boolean isAnnotationPresent([Class](../../../java/lang/Class.html "class in java.lang")<? extends [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")> annotationClass)  
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.  
Specified by:  
`[isAnnotationPresent](../../../java/lang/reflect/AnnotatedElement.html#isAnnotationPresent-java.lang.Class-)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Parameters:  
`annotationClass` \- the Class object corresponding to the annotation type  
Returns:  
true if an annotation for the specified annotation type is present on this element, else false  
Throws:  
`[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang")` \- if the given annotation class is null  
Since:  
1.5  
* #### getAnnotationsByType  
public <T extends [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")> T[] getAnnotationsByType([Class](../../../java/lang/Class.html "class in java.lang")<T> annotationClass)  
Returns annotations that are _associated_ with this element. If there are no annotations _associated_ with this element, the return value is an array of length 0\. The difference between this method and [AnnotatedElement.getAnnotation(Class)](../../../java/lang/reflect/AnnotatedElement.html#getAnnotation-java.lang.Class-) is that this method detects if its argument is a _repeatable annotation type_ (JLS 9.6), and if so, attempts to find one or more annotations of that type by "looking through" a container annotation. The caller of this method is free to modify the returned array; it will have no effect on the arrays returned to other callers.  
Specified by:  
`[getAnnotationsByType](../../../java/lang/reflect/AnnotatedElement.html#getAnnotationsByType-java.lang.Class-)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Type Parameters:  
`T` \- the type of the annotation to query for and return if present  
Parameters:  
`annotationClass` \- the Class object corresponding to the annotation type  
Returns:  
all this element's annotations for the specified annotation type if associated with this element, else an array of length zero  
Throws:  
`[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang")` \- if the given annotation class is null  
Since:  
1.8  
* #### getAnnotations  
public [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")[] getAnnotations()  
Returns annotations that are _present_ on this element. If there are no annotations _present_ on this element, the return value is an array of length 0\. The caller of this method is free to modify the returned array; it will have no effect on the arrays returned to other callers.  
Specified by:  
`[getAnnotations](../../../java/lang/reflect/AnnotatedElement.html#getAnnotations--)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Returns:  
annotations present on this element  
Since:  
1.5  
* #### getDeclaredAnnotation  
public <T extends [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")> T getDeclaredAnnotation([Class](../../../java/lang/Class.html "class in java.lang")<T> annotationClass)  
Returns this element's annotation for the specified type if such an annotation is _directly present_, else null. This method ignores inherited annotations. (Returns null if no annotations are directly present on this element.)  
Specified by:  
`[getDeclaredAnnotation](../../../java/lang/reflect/AnnotatedElement.html#getDeclaredAnnotation-java.lang.Class-)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Type Parameters:  
`T` \- the type of the annotation to query for and return if directly present  
Parameters:  
`annotationClass` \- the Class object corresponding to the annotation type  
Returns:  
this element's annotation for the specified annotation type if directly present on this element, else null  
Throws:  
`[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang")` \- if the given annotation class is null  
Since:  
1.8  
* #### getDeclaredAnnotationsByType  
public <T extends [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")> T[] getDeclaredAnnotationsByType([Class](../../../java/lang/Class.html "class in java.lang")<T> annotationClass)  
Returns this element's annotation(s) for the specified type if such annotations are either _directly present_ or_indirectly present_. This method ignores inherited annotations. If there are no specified annotations directly or indirectly present on this element, the return value is an array of length 0\. The difference between this method and [AnnotatedElement.getDeclaredAnnotation(Class)](../../../java/lang/reflect/AnnotatedElement.html#getDeclaredAnnotation-java.lang.Class-) is that this method detects if its argument is a _repeatable annotation type_ (JLS 9.6), and if so, attempts to find one or more annotations of that type by "looking through" a container annotation if one is present. The caller of this method is free to modify the returned array; it will have no effect on the arrays returned to other callers.  
Specified by:  
`[getDeclaredAnnotationsByType](../../../java/lang/reflect/AnnotatedElement.html#getDeclaredAnnotationsByType-java.lang.Class-)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Type Parameters:  
`T` \- the type of the annotation to query for and return if directly or indirectly present  
Parameters:  
`annotationClass` \- the Class object corresponding to the annotation type  
Returns:  
all this element's annotations for the specified annotation type if directly or indirectly present on this element, else an array of length zero  
Throws:  
`[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang")` \- if the given annotation class is null  
Since:  
1.8  
* #### getDeclaredAnnotations  
public [Annotation](../../../java/lang/annotation/Annotation.html "interface in java.lang.annotation")[] getDeclaredAnnotations()  
Returns annotations that are _directly present_ on this element. This method ignores inherited annotations. If there are no annotations _directly present_ on this element, the return value is an array of length 0\. The caller of this method is free to modify the returned array; it will have no effect on the arrays returned to other callers.  
Specified by:  
`[getDeclaredAnnotations](../../../java/lang/reflect/AnnotatedElement.html#getDeclaredAnnotations--)` in interface `[AnnotatedElement](../../../java/lang/reflect/AnnotatedElement.html "interface in java.lang.reflect")`  
Returns:  
annotations directly present on this element  
Since:  
1.5

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AccessibleObject (Java Platform SE 8 ) (original) (raw)

Constructor Summary

Method Summary

Constructor Detail

Method Detail