1. Description
2. Field Summary
3. Method Summary
   1. Methods declared in class Executable
   2. Methods declared in class AccessibleObject
   3. Methods declared in class Object
4. Method Details
   1. setAccessible(boolean)
   2. getDeclaringClass()
   3. getName()
   4. getModifiers()
   5. getTypeParameters()
   6. getParameterTypes()
   7. getParameterCount()
   8. getGenericParameterTypes()
   9. getExceptionTypes()
   10. getGenericExceptionTypes()
   11. equals(Object)
   12. hashCode()
   13. toString()
   14. toGenericString()
   15. newInstance(Object...)
   16. isVarArgs()
   17. isSynthetic()
   18. getAnnotation(Class)
   19. getDeclaredAnnotations()
   20. getParameterAnnotations()
   21. getAnnotatedReturnType()
   22. getAnnotatedReceiverType()

• Field Summary

  Fields declared in interface Member

  DECLARED, PUBLIC

  Modifier and Type

  Field

  Description

  static final int

  DECLARED

  Identifies the set of declared members of a class or interface.

  static final int

  PUBLIC

  Identifies the set of all public members of a class or interface, including inherited members.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  boolean

  equals(Object obj)

  Compares this Constructor against the specified object.

  AnnotatedType

  getAnnotatedReceiverType()

  Returns an AnnotatedType object that represents the use of a type to specify the receiver type of the method/constructor represented by this Executable object.

  AnnotatedType

  getAnnotatedReturnType()

  Returns an AnnotatedType object that represents the use of a type to specify the return type of the method/constructor represented by this Executable.

  <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[]

  getDeclaredAnnotations()

  Returns annotations that are directly present on this element.

  Class<T>

  getDeclaringClass()

  Returns the Class object representing the class that declares the constructor represented by this object.

  Class<?>[]

  getExceptionTypes()

  Returns an array of Class objects that represent the types of exceptions declared to be thrown by the underlying executable represented by this object.

  Type[]

  getGenericExceptionTypes()

  Returns an array of Type objects that represent the exceptions declared to be thrown by this executable object.

  Type[]

  getGenericParameterTypes()

  Returns an array of Type objects that represent the formal parameter types, in declaration order, of the executable represented by this object.

  int

  getModifiers()

  Returns the Java language modifiers for the executable represented by this object.

  String

  getName()

  Returns the name of this constructor, as a string.

  Annotation[][]

  getParameterAnnotations()

  Returns an array of arrays of Annotations that represent the annotations on the formal parameters, in declaration order, of the Executable represented by this object.

  int

  getParameterCount()

  Returns the number of formal parameters (whether explicitly declared or implicitly declared or neither) for the executable represented by this object.

  Class<?>[]

  getParameterTypes()

  Returns an array of Class objects that represent the formal parameter types, in declaration order, of the executable represented by this object.

  TypeVariable<Constructor<T>>[]

  getTypeParameters()

  Returns an array of TypeVariable objects that represent the type variables declared by the generic declaration represented by this GenericDeclaration object, in declaration order.

  int

  hashCode()

  Returns a hashcode for this Constructor.

  boolean

  isSynthetic()

  Returns true if this executable is a synthetic construct; returns false otherwise.

  boolean

  isVarArgs()

  Returns true if this executable was declared to take a variable number of arguments; returns false otherwise.

  T

  newInstance(Object... initargs)

  Uses the constructor represented by this Constructor object to create and initialize a new instance of the constructor's declaring class, with the specified initialization parameters.

  void

  setAccessible(boolean flag)

  Set the accessible flag for this reflected object to the indicated boolean value.

  String

  toGenericString()

  Returns a string describing this Constructor, including type parameters.

  String

  toString()

  Returns a string describing this Constructor.

  Methods declared in class Executable

  accessFlags, getAnnotatedExceptionTypes, getAnnotatedParameterTypes, getAnnotationsByType, getParameters

  Modifier and Type

  Method

  Description

  Set<AccessFlag>

  accessFlags()

  Returns an unmodifiable set of the access flags for the executable represented by this object, possibly empty.

  AnnotatedType[]

  getAnnotatedExceptionTypes()

  Returns an array of AnnotatedType objects that represent the use of types to specify the declared exceptions of the method/constructor represented by this Executable.

  AnnotatedType[]

  getAnnotatedParameterTypes()

  Returns an array of AnnotatedType objects that represent the use of types to specify formal parameter types of the method/constructor represented by this Executable.

  <T extends Annotation>
  T[]

  getAnnotationsByType(Class<T> annotationClass)

  Returns annotations that are associated with this element.

  Parameter[]

  getParameters()

  Returns an array of Parameter objects representing all the parameters to the underlying executable represented by this object.

  Methods declared in class AccessibleObject

  canAccess, getAnnotations, getDeclaredAnnotation, getDeclaredAnnotationsByType, isAccessible, isAnnotationPresent, setAccessible, trySetAccessible

  Modifier and Type

  Method

  Description

  final boolean

  canAccess(Object obj)

  Test if the caller can access this reflected object.

  Annotation[]

  getAnnotations()

  Returns annotations that are present on 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.

  <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()

  Deprecated.

  This method is deprecated because its name hints that it checks if the reflected object is accessible when it actually indicates if the checks for Java language access control are suppressed.

  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 reflected objects.

  final boolean

  trySetAccessible()

  Set the accessible flag for this reflected object to true if possible.

  Methods declared in class Object

  clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

• Method Details

  • setAccessible

    public void setAccessible(boolean flag)

    Set the accessible flag for this reflected object to the indicated boolean value. A value of true indicates that the reflected object should suppress checks for Java language access control when it is used. A value of false indicates that the reflected object should enforce checks for Java language access control when it is used, with the variation noted in the class description.

    This method may be used by a caller in class C to enable access to a member of declaring class D if any of the following hold:

    • C and D are in the same module.
    • The member is public and D is public in a package that the module containing D exports to at least the module containing C.
    • The member is protected static, D is public in a package that the module containing D exports to at least the module containing C, and C is a subclass of D.
    • D is in a package that the module containing D opens to at least the module containing C. All packages in unnamed and open modules are open to all modules and so this method always succeeds when D is in an unnamed or open module.

    This method may be used by JNI code with no caller class on the stack to enable access to a member of declaring class D if and only if:

    • The member is public and D is public in a package that the module containing D exports unconditionally.

    This method cannot be used to enable access to private members, members with default (package) access, protected instance members, or protected constructors when the declaring class is in a different module to the caller and the package containing the declaring class is not open to the caller's module.

    A SecurityException is thrown if this object is a Constructor object for the class Class and flag is true.

    Overrides: setAccessible in class AccessibleObject Parameters: flag - the new value for the accessible flag Throws: InaccessibleObjectException - if access cannot be enabled SecurityException - if this is a constructor for java.lang.Class External Specifications

    • Java Native Interface Specification

    See Also:

    • AccessibleObject.trySetAccessible()
    • MethodHandles.privateLookupIn(Class, MethodHandles.Lookup)

  • getDeclaringClass

    public Class<T> getDeclaringClass()

    Returns the Class object representing the class that declares the constructor represented by this object.

    Specified by: getDeclaringClass in interface Member Specified by: getDeclaringClass in class Executable Returns: an object representing the declaring class of the underlying member

  • getName

    public String getName()

    Returns the name of this constructor, as a string. This is the binary name of the constructor's declaring class.

    Specified by: getName in interface Member Specified by: getName in class Executable Returns: the simple name of the underlying member

  • getModifiers

    public int getModifiers()

    Returns the Java language modifiers for the executable represented by this object.

    Specified by: getModifiers in interface Member Specified by: getModifiers in class Executable Returns: the Java language modifiers for the executable represented by this object See Java Language Specification: 8.8.3 Constructor Modifiers
    See Also:

    • Executable.accessFlags()

  • getTypeParameters

    public TypeVariable<Constructor<T>>[] getTypeParameters()

    Returns an array of TypeVariable objects that represent the type variables declared by the generic declaration represented by this GenericDeclaration object, in declaration order. Returns an array of length 0 if the underlying generic declaration declares no type variables.

    Specified by: getTypeParameters in interface GenericDeclaration Specified by: getTypeParameters in class Executable Returns: an array of TypeVariable objects that represent the type variables declared by this generic declaration Throws: GenericSignatureFormatError - if the generic signature of this generic declaration does not conform to the format specified in The Java Virtual Machine Specification Since: 1.5

  • getParameterTypes

    public Class<?>[] getParameterTypes()

    Returns an array of Class objects that represent the formal parameter types, in declaration order, of the executable represented by this object. Returns an array of length 0 if the underlying executable takes no parameters. Note that the constructors of some inner classes may have an implicitly declared parameter in addition to explicitly declared ones. Also note that compact constructors of a record class may have implicitly declared parameters.

    Specified by: getParameterTypes in class Executable Returns: the parameter types for the executable this object represents

  • getParameterCount

    public int getParameterCount()

    Returns the number of formal parameters (whether explicitly declared or implicitly declared or neither) for the executable represented by this object.

    Specified by: getParameterCount in class Executable Returns: The number of formal parameters for the executable this object represents Since: 1.8

  • getGenericParameterTypes

    public Type[] getGenericParameterTypes()

    Returns an array of Type objects that represent the formal parameter types, in declaration order, of the executable represented by this object. An array of length 0 is returned if the underlying executable takes no parameters. Note that the constructors of some inner classes may have an implicitly declared parameter in addition to explicitly declared ones. Compact constructors of a record class may also have implicitly declared parameters, but they are a special case and thus considered as if they had been explicitly declared in the source. Finally note that as a modeling artifact, the number of returned parameters can differ depending on whether or not generic information is present. If generic information is present, parameters explicitly present in the source or parameters of compact constructors of a record class will be returned. Note that parameters of compact constructors of a record class are a special case, as they are not explicitly present in the source, and its type will be returned regardless of the parameters being implicitly declared or not. If generic information is not present, implicit and synthetic parameters may be returned as well.

    If a formal parameter type is a parameterized type, the Type object returned for it must accurately reflect the actual type arguments used in the source code. This assertion also applies to the parameters of compact constructors of a record class, independently of them being implicitly declared or not.

    If a formal parameter type is a type variable or a parameterized type, it is created. Otherwise, it is resolved.

    Overrides: getGenericParameterTypes in class Executable Returns: an array of Types that represent the formal parameter types of the underlying executable, in declaration order Throws: GenericSignatureFormatError - if the generic method signature does not conform to the format specified in The Java Virtual Machine Specification TypeNotPresentException - if any of the parameter types of the underlying executable refers to a non-existent type declaration MalformedParameterizedTypeException - if any of the underlying executable's parameter types refer to a parameterized type that cannot be instantiated for any reason Since: 1.5

  • getExceptionTypes

    public Class<?>[] getExceptionTypes()

    Returns an array of Class objects that represent the types of exceptions declared to be thrown by the underlying executable represented by this object. Returns an array of length 0 if the executable declares no exceptions in its throws clause.

    Specified by: getExceptionTypes in class Executable Returns: the exception types declared as being thrown by the executable this object represents

  • getGenericExceptionTypes

    public Type[] getGenericExceptionTypes()

    Returns an array of Type objects that represent the exceptions declared to be thrown by this executable object. Returns an array of length 0 if the underlying executable declares no exceptions in its throws clause.

    If an exception type is a type variable or a parameterized type, it is created. Otherwise, it is resolved.

    Overrides: getGenericExceptionTypes in class Executable Returns: an array of Types that represent the exception types thrown by the underlying executable Throws: GenericSignatureFormatError - if the generic method signature does not conform to the format specified in The Java Virtual Machine Specification TypeNotPresentException - if the underlying executable's throws clause refers to a non-existent type declaration MalformedParameterizedTypeException - if the underlying executable's throws clause refers to a parameterized type that cannot be instantiated for any reason Since: 1.5

  • equals

    public boolean equals(Object obj)

    Compares this Constructor against the specified object. Returns true if the objects are the same. Two Constructor objects are the same if they were declared by the same class and have the same formal parameter types.

    Overrides: equals in class Object Parameters: obj - the reference object with which to compare. Returns: true if this object is the same as the obj argument; false otherwise. See Also:

    • Object.hashCode()
    • HashMap

  • hashCode

    public int hashCode()

    Returns a hashcode for this Constructor. The hashcode is the same as the hashcode for the underlying constructor's declaring class name.

    Overrides: hashCode in class Object Returns: a hash code value for this object See Also:

    • Object.equals(java.lang.Object)
    • System.identityHashCode(Object)

  • toString

    public String toString()

    Returns a string describing this Constructor. The string is formatted as the constructor access modifiers, if any, followed by the fully-qualified name of the declaring class, followed by a parenthesized, comma-separated list of the constructor's formal parameter types. For example: public java.util.HashMap(int,float)

    If the constructor is declared to throw exceptions, the parameter list is followed by a space, followed by the word "throws" followed by a comma-separated list of the thrown exception types.

    The only possible modifiers for constructors are the access modifiers public, protected or private. Only one of these may appear, or none if the constructor has default (package) access.

    Overrides: toString in class Object Returns: a string describing this Constructor See Java Language Specification: 8.8.3 Constructor Modifiers
    8.9.2 Enum Body Declarations
    

  • toGenericString

    public String toGenericString()

    Returns a string describing this Constructor, including type parameters. The string is formatted as the constructor access modifiers, if any, followed by an angle-bracketed comma separated list of the constructor's type parameters, if any, including informative bounds of the type parameters, if any, followed by the fully-qualified name of the declaring class, followed by a parenthesized, comma-separated list of the constructor's generic formal parameter types. If this constructor was declared to take a variable number of arguments, instead of denoting the last parameter as "Type[]", it is denoted as "Type...". A space is used to separate access modifiers from one another and from the type parameters or class name. If there are no type parameters, the type parameter list is elided; if the type parameter list is present, a space separates the list from the class name. If the constructor is declared to throw exceptions, the parameter list is followed by a space, followed by the word "throws" followed by a comma-separated list of the generic thrown exception types.

    The only possible modifiers for constructors are the access modifiers public, protected or private. Only one of these may appear, or none if the constructor has default (package) access.

    Specified by: toGenericString in class Executable Returns: a string describing this Constructor, include type parameters See Java Language Specification: 8.8.3 Constructor Modifiers
    8.9.2 Enum Body Declarations
    Since: 1.5

  • newInstance

    public T newInstance(Object... initargs) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException

    Uses the constructor represented by this Constructor object to create and initialize a new instance of the constructor's declaring class, with the specified initialization parameters. Individual parameters are automatically unwrapped to match primitive formal parameters, and both primitive and reference parameters are subject to method invocation conversions as necessary.

    If the number of formal parameters required by the underlying constructor is 0, the supplied initargs array may be of length 0 or null.

    If the constructor's declaring class is an inner class in a non-static context, the first argument to the constructor needs to be the enclosing instance; see section 15.9.3 of The Java Language Specification.

    If the required access and argument checks succeed and the instantiation will proceed, the constructor's declaring class is initialized if it has not already been initialized.

    If the constructor completes normally, returns the newly created and initialized instance.

    Parameters: initargs - array of objects to be passed as arguments to the constructor call; values of primitive types are wrapped in a wrapper object of the appropriate type (e.g. a float in a Float) Returns: a new object created by calling the constructor this object represents Throws: IllegalAccessException - if this Constructor object is enforcing Java language access control and the underlying constructor is inaccessible. IllegalArgumentException - if the number of actual and formal parameters differ; if an unwrapping conversion for primitive arguments fails; or if, after possible unwrapping, a parameter value cannot be converted to the corresponding formal parameter type by a method invocation conversion; if this constructor pertains to an enum class. InstantiationException - if the class that declares the underlying constructor represents an abstract class. InvocationTargetException - if the underlying constructor throws an exception. ExceptionInInitializerError - if the initialization provoked by this method fails.

  • isVarArgs

    public boolean isVarArgs()

    Returns true if this executable was declared to take a variable number of arguments; returns false otherwise.

    Overrides: isVarArgs in class Executable Returns: true if this executable was declared to take a variable number of arguments; returns false otherwise See Java Language Specification: 8.4.1 Formal Parameters
    Since: 1.5

  • isSynthetic

    public boolean isSynthetic()

    Returns true if this executable is a synthetic construct; returns false otherwise.

    Specified by: isSynthetic in interface Member Overrides: isSynthetic in class Executable Returns: true if and only if this executable is a synthetic construct as defined by The Java Language Specification. See Java Language Specification: 13.1 The Form of a Binary
    See Java Virtual Machine Specification: 4.6 Methods
    Since: 1.5 See Also:

    • Java programming language and JVM modeling in core reflection

  • getAnnotation

    public <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.

    Note that any annotation returned by this method is a declaration annotation.

    Specified by: getAnnotation in interface AnnotatedElement Overrides: getAnnotation in class Executable 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 - if the given annotation class is null Since: 1.5

  • getDeclaredAnnotations

    public 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.

    Note that any annotations returned by this method are declaration annotations.

    Specified by: getDeclaredAnnotations in interface AnnotatedElement Overrides: getDeclaredAnnotations in class AccessibleObject Returns: annotations directly present on this element Since: 1.5

  • getParameterAnnotations

    public Annotation[][] getParameterAnnotations()

    Returns an array of arrays of Annotations that represent the annotations on the formal parameters, in declaration order, of the Executable represented by this object. Synthetic and mandated parameters (see explanation below), such as the outer "this" parameter to an inner class constructor will be represented in the returned array. If the executable has no parameters (meaning no formal, no synthetic, and no mandated parameters), a zero-length array will be returned. If the Executable has one or more parameters, a nested array of length zero is returned for each parameter with no annotations. The annotation objects contained in the returned arrays are serializable. The caller of this method is free to modify the returned arrays; it will have no effect on the arrays returned to other callers. A compiler may add extra parameters that are implicitly declared in source ("mandated"), as well as parameters that are neither implicitly nor explicitly declared in source ("synthetic") to the parameter list for a method. See Parameter for more information.

    Note that any annotations returned by this method are declaration annotations.

    Specified by: getParameterAnnotations in class Executable Returns: an array of arrays that represent the annotations on the formal and implicit parameters, in declaration order, of the executable represented by this object Since: 1.5 See Also:

    • Parameter
    • Parameter.getAnnotations()

  • getAnnotatedReturnType

    public AnnotatedType getAnnotatedReturnType()

    Returns an AnnotatedType object that represents the use of a type to specify the return type of the method/constructor represented by this Executable. If this Executable object represents a constructor, the AnnotatedType object represents the type of the constructed object. If this Executable object represents a method, the AnnotatedType object represents the use of a type to specify the return type of the method.

    Specified by: getAnnotatedReturnType in class Executable Returns: an object representing the return type of the method or constructor represented by this Executable Since: 1.8

  • getAnnotatedReceiverType

    public AnnotatedType getAnnotatedReceiverType()

    Returns an AnnotatedType object that represents the use of a type to specify the receiver type of the method/constructor represented by this Executable object. The receiver type of a method/constructor is available only if the method/constructor has a receiver parameter (JLS 8.4.1). If this Executable object represents an instance method or represents a constructor of an inner member class, and the method/constructor either has no receiver parameter or has a receiver parameter with no annotations on its type, then the return value is an AnnotatedType object representing an element with no annotations. If this Executable object represents a static method or represents a constructor of a top level, static member, local, or anonymous class, then the return value is null.

    Overrides: getAnnotatedReceiverType in class Executable Returns: an object representing the receiver type of the method or constructor represented by this Executable or null if this Executable can not have a receiver parameter Since: 1.8

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