Module java.base

Class AccessibleObject

All Implemented Interfaces:
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 (known as reflected objects). It provides the ability to flag a reflected object as suppressing checks for Java language access control when it is used. This 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.

Java language access control prevents use of private members outside their top-level class; package access members outside their package; protected members outside their package or subclasses; and public members outside their module unless they are declared in an exported package and the user reads their module. By default, Java language access control is enforced (with one variation) when Fields, Methods, or Constructors are used to get or set fields, to invoke methods, or to create and initialize new instances of classes, respectively. Every reflected object checks that the code using it is in an appropriate class, package, or module. The check when invoked by JNI code with no Java class on the stack only succeeds if the member and the declaring class are public, and the class is in a package that is exported to all modules.

The one variation from Java language access control is that the checks by reflected objects assume readability. That is, the module containing the use of a reflected object is assumed to read the module in which the underlying field, method, or constructor is declared.

Whether the checks for Java language access control can be suppressed (and thus, whether access can be enabled) depends on whether the reflected object corresponds to a member in an exported or open package (see setAccessible(boolean)).

See Java Language Specification:
6.6 Access Control
External Specifications