AccessibleObject

java.lang.Object
- java.lang.reflect.AccessibleObject

所有已实现的接口:

AnnotatedElement

直接已知子类:

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.

从以下版本开始:

1.2

另请参阅:

Field, Method, Constructor, ReflectPermission

构造器概要

构造器
限定符构造器说明

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

构造器
限定符	构造器	说明
`protected`	`AccessibleObject()`	Constructor: only used by the Java Virtual Machine.

方法概要

所有方法静态方法实例方法具体方法
限定符和类型	方法	说明
`<T extends Annotation> T`	`getAnnotation(Class<T> 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<T> annotationClass)`	Returns annotations that are associated with this element.
`<T extends Annotation> T`	`getDeclaredAnnotation(Class<T> 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<T> 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.
`void`	`setAccessible(boolean flag)`	Set the `accessible` flag for this object to the indicated boolean value.
`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).

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 构造器详细资料
  - AccessibleObject
```
protected AccessibleObject()
```
    Constructor: only used by the Java Virtual Machine.
- 方法详细资料
  - setAccessible
```
public static void setAccessible(AccessibleObject[] array,
                                 boolean flag)
                          throws SecurityException
```
    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 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.
    
    参数:
    
    array - the array of AccessibleObjects
    
    flag - the new value for the accessible flag in each object
    
    抛出:
    
    SecurityException - if the request is denied.
    
    另请参阅:
    
    SecurityManager.checkPermission(java.security.Permission), RuntimePermission
  - setAccessible
```
public void setAccessible(boolean flag)
                   throws SecurityException
```
    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 Class).
    A SecurityException is raised if this object is a Constructor object for the class java.lang.Class, and flag is true.
    
    参数:
    
    flag - the new value for the accessible flag
    
    抛出:
    
    SecurityException - if the request is denied.
    
    另请参阅:
    
    SecurityManager.checkPermission(java.security.Permission), RuntimePermission
  - isAccessible
```
public boolean isAccessible()
```
    Get the value of the accessible flag for this object.
    
    返回:
    
    the value of the object's accessible flag
  - getAnnotation
```
public <T extends Annotation> T getAnnotation(Class<T> annotationClass)
```
    从接口复制的说明: AnnotatedElement
    
    Returns this element's annotation for the specified type if such an annotation is present, else null.
    
    指定者:
    
    getAnnotation 在接口中 AnnotatedElement
    
    类型参数:
    
    T - the type of the annotation to query for and return if present
    
    参数:
    
    annotationClass - the Class object corresponding to the annotation type
    
    返回:
    
    this element's annotation for the specified annotation type if present on this element, else null
    
    抛出:
    
    NullPointerException - if the given annotation class is null
    
    从以下版本开始:
    
    1.5
  - isAnnotationPresent
```
public boolean isAnnotationPresent(Class<? extends 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.
    
    指定者:
    
    isAnnotationPresent 在接口中 AnnotatedElement
    
    参数:
    
    annotationClass - the Class object corresponding to the annotation type
    
    返回:
    
    true if an annotation for the specified annotation type is present on this element, else false
    
    抛出:
    
    NullPointerException - if the given annotation class is null
    
    从以下版本开始:
    
    1.5
  - getAnnotationsByType
```
public <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass)
```
    从接口复制的说明: AnnotatedElement
    
    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(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.
    
    指定者:
    
    getAnnotationsByType 在接口中 AnnotatedElement
    
    类型参数:
    
    T - the type of the annotation to query for and return if present
    
    参数:
    
    annotationClass - the Class object corresponding to the annotation type
    
    返回:
    
    all this element's annotations for the specified annotation type if associated with this element, else an array of length zero
    
    抛出:
    
    NullPointerException - if the given annotation class is null
    
    从以下版本开始:
    
    1.8
  - getAnnotations
```
public Annotation[] getAnnotations()
```
    从接口复制的说明: AnnotatedElement
    
    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.
    
    指定者:
    
    getAnnotations 在接口中 AnnotatedElement
    
    返回:
    
    annotations present on this element
    
    从以下版本开始:
    
    1.5
  - getDeclaredAnnotation
```
public <T extends Annotation> T getDeclaredAnnotation(Class<T> annotationClass)
```
    从接口复制的说明: AnnotatedElement
    
    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.)
    
    指定者:
    
    getDeclaredAnnotation 在接口中 AnnotatedElement
    
    类型参数:
    
    T - the type of the annotation to query for and return if directly present
    
    参数:
    
    annotationClass - the Class object corresponding to the annotation type
    
    返回:
    
    this element's annotation for the specified annotation type if directly present on this element, else null
    
    抛出:
    
    NullPointerException - if the given annotation class is null
    
    从以下版本开始:
    
    1.8
  - getDeclaredAnnotationsByType
```
public <T extends Annotation> T[] getDeclaredAnnotationsByType(Class<T> annotationClass)
```
    从接口复制的说明: AnnotatedElement
    
    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(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.
    
    指定者:
    
    getDeclaredAnnotationsByType 在接口中 AnnotatedElement
    
    类型参数:
    
    T - the type of the annotation to query for and return if directly or indirectly present
    
    参数:
    
    annotationClass - the Class object corresponding to the annotation type
    
    返回:
    
    all this element's annotations for the specified annotation type if directly or indirectly present on this element, else an array of length zero
    
    抛出:
    
    NullPointerException - if the given annotation class is null
    
    从以下版本开始:
    
    1.8
  - getDeclaredAnnotations
```
public Annotation[] getDeclaredAnnotations()
```
    从接口复制的说明: AnnotatedElement
    
    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.
    
    指定者:
    
    getDeclaredAnnotations 在接口中 AnnotatedElement
    
    返回:
    
    annotations directly present on this element
    
    从以下版本开始:
    
    1.5

类 AccessibleObject

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

AccessibleObject

方法详细资料

setAccessible

setAccessible

isAccessible

getAnnotation

isAnnotationPresent

getAnnotationsByType

getAnnotations

getDeclaredAnnotation

getDeclaredAnnotationsByType

getDeclaredAnnotations