Module java.base

Package java.lang.reflect

Provides classes and interfaces for obtaining reflective information about classes and objects. Reflection allows programmatic access to information about the fields, methods and constructors of loaded classes, and the use of reflected fields, methods, and constructors to operate on their underlying counterparts, within encapsulation and security restrictions.

AccessibleObject allows suppression of access checks if the necessary ReflectPermission is available.

Array provides static methods to dynamically create and access arrays.

Classes in this package, along with java.lang.Class accommodate applications such as debuggers, interpreters, object inspectors, class browsers, and services such as Object Serialization and JavaBeans that need access to either the public members of a target object (based on its runtime class) or the members declared by a given class.

Since:

1.1

Interface Summary

Interface	Description
AnnotatedArrayType	AnnotatedArrayType represents the potentially annotated use of an array type, whose component type may itself represent the annotated use of a type.
AnnotatedElement	Represents an annotated construct of the program currently running in this VM.
AnnotatedParameterizedType	AnnotatedParameterizedType represents the potentially annotated use of a parameterized type, whose type arguments may themselves represent annotated uses of types.
AnnotatedType	AnnotatedType represents the potentially annotated use of a type in the program currently running in this VM.
AnnotatedTypeVariable	AnnotatedTypeVariable represents the potentially annotated use of a type variable, whose declaration may have bounds which themselves represent annotated uses of types.
AnnotatedWildcardType	AnnotatedWildcardType represents the potentially annotated use of a wildcard type argument, whose upper or lower bounds may themselves represent annotated uses of types.
GenericArrayType	GenericArrayType represents an array type whose component type is either a parameterized type or a type variable.
GenericDeclaration	A common interface for all entities that declare type variables.
InvocationHandler	InvocationHandler is the interface implemented by the invocation handler of a proxy instance.
Member	Member is an interface that reflects identifying information about a single member (a field or a method) or a constructor.
ParameterizedType	ParameterizedType represents a parameterized type such as Collection<String>.
Type	Type is the common superinterface for all types in the Java programming language.
TypeVariable<D extends GenericDeclaration>	TypeVariable is the common superinterface for type variables of kinds.
WildcardType	WildcardType represents a wildcard type expression, such as ?, ? extends Number, or ? super Integer.

Class Summary

Class	Description
AccessibleObject	The AccessibleObject class is the base class for Field, Method, and Constructor objects (known as reflected objects).
Array	The Array class provides static methods to dynamically create and access Java arrays.
Constructor<T>	Constructor provides information about, and access to, a single constructor for a class.
Executable	A shared superclass for the common functionality of Method and Constructor.
Field	A Field provides information about, and dynamic access to, a single field of a class or an interface.
Method	A Method provides information about, and access to, a single method on a class or interface.
Modifier	The Modifier class provides static methods and constants to decode class and member access modifiers.
Parameter	Information about method parameters.
Proxy	Proxy provides static methods for creating objects that act like instances of interfaces but allow for customized method invocation.
RecordComponent	Associated with records, a preview feature of the Java language. A RecordComponent provides information about, and dynamic access to, a component of a record class.
ReflectPermission	The Permission class for reflective operations.

Exception Summary

Exception	Description
InaccessibleObjectException	Thrown when Java language access checks cannot be suppressed.
InvocationTargetException	InvocationTargetException is a checked exception that wraps an exception thrown by an invoked method or constructor.
MalformedParameterizedTypeException	Thrown when a semantically malformed parameterized type is encountered by a reflective method that needs to instantiate it.
MalformedParametersException	Thrown when the java.lang.reflect package attempts to read method parameters from a class file and determines that one or more parameters are malformed.
UndeclaredThrowableException	Thrown by a method invocation on a proxy instance if its invocation handler's invoke method throws a checked exception (a Throwable that is not assignable to RuntimeException or Error) that is not assignable to any of the exception types declared in the throws clause of the method that was invoked on the proxy instance and dispatched to the invocation handler.

Error Summary

Error	Description
GenericSignatureFormatError	Thrown when a syntactically malformed signature attribute is encountered by a reflective method that needs to interpret the generic signature information for a type, method or constructor.