1. Description
2. Field Summary
3. Method Summary
   1. Methods declared in class AccessibleObject
   2. Methods declared in class Object
4. Method Details
   1. setAccessible(boolean)
   2. getDeclaringClass()
   3. getName()
   4. getModifiers()
   5. accessFlags()
   6. isEnumConstant()
   7. isSynthetic()
   8. getType()
   9. getGenericType()
   10. equals(Object)
   11. hashCode()
   12. toString()
   13. toGenericString()
   14. get(Object)
   15. getBoolean(Object)
   16. getByte(Object)
   17. getChar(Object)
   18. getShort(Object)
   19. getInt(Object)
   20. getLong(Object)
   21. getFloat(Object)
   22. getDouble(Object)
   23. set(Object, Object)
   24. setBoolean(Object, boolean)
   25. setByte(Object, byte)
   26. setChar(Object, char)
   27. setShort(Object, short)
   28. setInt(Object, int)
   29. setLong(Object, long)
   30. setFloat(Object, float)
   31. setDouble(Object, double)
   32. getAnnotation(Class)
   33. getAnnotationsByType(Class)
   34. getAnnotatedType()

• 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

  Set<AccessFlag>

  accessFlags()

  Returns an unmodifiable set of the access flags for this field, possibly empty.

  boolean

  equals(Object obj)

  Compares this Field against the specified object.

  Object

  get(Object obj)

  Returns the value of the field represented by this Field, on the specified object.

  AnnotatedType

  getAnnotatedType()

  Returns an AnnotatedType object that represents the use of a type to specify the declared type of the field represented by this Field.

  <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.

  <T extends Annotation>
  T[]

  getAnnotationsByType(Class<T> annotationClass)

  Returns annotations that are associated with this element.

  boolean

  getBoolean(Object obj)

  Gets the value of a static or instance boolean field.

  byte

  getByte(Object obj)

  Gets the value of a static or instance byte field.

  char

  getChar(Object obj)

  Gets the value of a static or instance field of type char or of another primitive type convertible to type char via a widening conversion.

  Class<?>

  getDeclaringClass()

  Returns the Class object representing the class or interface that declares the field represented by this Field object.

  double

  getDouble(Object obj)

  Gets the value of a static or instance field of type double or of another primitive type convertible to type double via a widening conversion.

  float

  getFloat(Object obj)

  Gets the value of a static or instance field of type float or of another primitive type convertible to type float via a widening conversion.

  Type

  getGenericType()

  Returns a Type object that represents the declared type for the field represented by this Field object.

  int

  getInt(Object obj)

  Gets the value of a static or instance field of type int or of another primitive type convertible to type int via a widening conversion.

  long

  getLong(Object obj)

  Gets the value of a static or instance field of type long or of another primitive type convertible to type long via a widening conversion.

  int

  getModifiers()

  Returns the Java language modifiers for the field represented by this Field object, as an integer.

  String

  getName()

  Returns the name of the field represented by this Field object.

  short

  getShort(Object obj)

  Gets the value of a static or instance field of type short or of another primitive type convertible to type short via a widening conversion.

  Class<?>

  getType()

  Returns a Class object that identifies the declared type for the field represented by this Field object.

  int

  hashCode()

  Returns a hashcode for this Field.

  boolean

  isEnumConstant()

  Returns true if this field represents an element of an enumerated class; returns false otherwise.

  boolean

  isSynthetic()

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

  void

  set(Object obj, Object value)

  Sets the field represented by this Field object on the specified object argument to the specified new value.

  void

  setAccessible(boolean flag)

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

  void

  setBoolean(Object obj, boolean z)

  Sets the value of a field as a boolean on the specified object.

  void

  setByte(Object obj, byte b)

  Sets the value of a field as a byte on the specified object.

  void

  setChar(Object obj, char c)

  Sets the value of a field as a char on the specified object.

  void

  setDouble(Object obj, double d)

  Sets the value of a field as a double on the specified object.

  void

  setFloat(Object obj, float f)

  Sets the value of a field as a float on the specified object.

  void

  setInt(Object obj, int i)

  Sets the value of a field as an int on the specified object.

  void

  setLong(Object obj, long l)

  Sets the value of a field as a long on the specified object.

  void

  setShort(Object obj, short s)

  Sets the value of a field as a short on the specified object.

  String

  toGenericString()

  Returns a string describing this Field, including its generic type.

  String

  toString()

  Returns a string describing this Field.

  Methods declared in class AccessibleObject

  canAccess, getAnnotations, getDeclaredAnnotation, getDeclaredAnnotations, 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.

  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()

  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.

    If this reflected object represents a non-final field, and this method is used to enable access, then both read and write access to the field are enabled.

    If this reflected object represents a non-modifiable final field then enabling access only enables read access. Any attempt to set the field value throws an IllegalAccessException. The following fields are non-modifiable:

    • static final fields declared in any class or interface
    • final fields declared in a record
    • final fields declared in a hidden class

    If this reflected object represents a non-static final field in a class that is not a record class or hidden class, then enabling access will enable read access. Whether write access is allowed or not is checked when attempting to set the field value.

    Overrides: setAccessible in class AccessibleObject Parameters: flag - the new value for the accessible flag Throws: InaccessibleObjectException - if access cannot be enabled External Specifications

    • Java Native Interface Specification

    See Also:

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

  • getDeclaringClass

    public Class<?> getDeclaringClass()

    Returns the Class object representing the class or interface that declares the field represented by this Field object.

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

  • getName

    public String getName()

    Returns the name of the field represented by this Field object.

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

  • getModifiers

    public int getModifiers()

    Returns the Java language modifiers for the field represented by this Field object, as an integer. The Modifier class should be used to decode the modifiers.

    Specified by: getModifiers in interface Member Returns: the Java language modifiers for the underlying member See Java Language Specification: 8.3 Field Declarations
    9.3 Field (Constant) Declarations
    See Also:

    • Modifier
    • accessFlags()

  • accessFlags

    public Set<AccessFlag> accessFlags()

    Returns an unmodifiable set of the access flags for this field, possibly empty.

    Specified by: accessFlags in interface Member Returns: an unmodifiable set of the access flags for this field, possibly empty See Java Virtual Machine Specification: 4.5 Fields
    Since: 20 See Also:

    • getModifiers()

  • isEnumConstant

    public boolean isEnumConstant()

    Returns true if this field represents an element of an enumerated class; returns false otherwise.

    Returns: true if and only if this field represents an element of an enumerated class. See Java Language Specification: 8.9.1 Enum Constants
    Since: 1.5

  • isSynthetic

    public boolean isSynthetic()

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

    Specified by: isSynthetic in interface Member Returns: true if and only if this field is a synthetic field as defined by the Java Language Specification. Since: 1.5 See Also:

    • Java programming language and JVM modeling in core reflection

  • getType

    public Class<?> getType()

    Returns a Class object that identifies the declared type for the field represented by this Field object.

    Returns: a Class object identifying the declared type of the field represented by this object

  • getGenericType

    public Type getGenericType()

    Returns a Type object that represents the declared type for the field represented by this Field object.

    If the declared type of the field is a parameterized type, the Type object returned must accurately reflect the actual type arguments used in the source code.

    If the type of the underlying field is a type variable or a parameterized type, it is created. Otherwise, it is resolved.

    Returns: a Type object that represents the declared type for the field represented by this Field object Throws: GenericSignatureFormatError - if the generic field signature does not conform to the format specified in The Java Virtual Machine Specification TypeNotPresentException - if the generic type signature of the underlying field refers to a non-existent class or interface declaration MalformedParameterizedTypeException - if the generic signature of the underlying field refers to a parameterized type that cannot be instantiated for any reason Since: 1.5

  • equals

    public boolean equals(Object obj)

    Compares this Field against the specified object. Returns true if the objects are the same. Two Field objects are the same if they were declared by the same class and have the same name and type.

    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 Field. This is computed as the exclusive-or of the hashcodes for the underlying field's declaring class name and its 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 Field. The format is the access modifiers for the field, if any, followed by the field type, followed by a space, followed by the fully-qualified name of the class declaring the field, followed by a period, followed by the name of the field. For example: public static final int java.lang.Thread.MIN_PRIORITY private int java.io.FileDescriptor.fd

    The modifiers are placed in canonical order as specified by "The Java Language Specification". This is public, protected or private first, and then other modifiers in the following order: static, final, transient, volatile.

    Overrides: toString in class Object Returns: a string describing this Field See Java Language Specification: 8.3.1 Field Modifiers
    

  • toGenericString

    public String toGenericString()

    Returns a string describing this Field, including its generic type. The format is the access modifiers for the field, if any, followed by the generic field type, followed by a space, followed by the fully-qualified name of the class declaring the field, followed by a period, followed by the name of the field.

    The modifiers are placed in canonical order as specified by "The Java Language Specification". This is public, protected or private first, and then other modifiers in the following order: static, final, transient, volatile.

    Returns: a string describing this Field, including its generic type See Java Language Specification: 8.3.1 Field Modifiers
    Since: 1.5

  • get

    public Object get(Object obj) throws IllegalArgumentException, IllegalAccessException

    Returns the value of the field represented by this Field, on the specified object. The value is automatically wrapped in an object if it has a primitive type.

    The underlying field's value is obtained as follows:

    If the underlying field is a static field, the obj argument is ignored; it may be null.

    Otherwise, the underlying field is an instance field. If the specified obj argument is null, the method throws a NullPointerException. If the specified object is not an instance of the class or interface declaring the underlying field, the method throws an IllegalArgumentException.

    If this Field object is enforcing Java language access control, and the underlying field is inaccessible, the method throws an IllegalAccessException. If the underlying field is static, the class that declared the field is initialized if it has not already been initialized.

    Otherwise, the value is retrieved from the underlying instance or static field. If the field has a primitive type, the value is wrapped in an object before being returned, otherwise it is returned as is.

    If the field is hidden in the type of obj, the field's value is obtained according to the preceding rules.

    Parameters: obj - object from which the represented field's value is to be extracted Returns: the value of the represented field in object obj; primitive values are wrapped in an appropriate object before being returned Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof). NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails.

  • getBoolean

    public boolean getBoolean(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance boolean field.

    Parameters: obj - the object to extract the boolean value from Returns: the value of the boolean field Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type boolean by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getByte

    public byte getByte(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance byte field.

    Parameters: obj - the object to extract the byte value from Returns: the value of the byte field Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type byte by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getChar

    public char getChar(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance field of type char or of another primitive type convertible to type char via a widening conversion.

    Parameters: obj - the object to extract the char value from Returns: the value of the field converted to type char Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type char by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getShort

    public short getShort(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance field of type short or of another primitive type convertible to type short via a widening conversion.

    Parameters: obj - the object to extract the short value from Returns: the value of the field converted to type short Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type short by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getInt

    public int getInt(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance field of type int or of another primitive type convertible to type int via a widening conversion.

    Parameters: obj - the object to extract the int value from Returns: the value of the field converted to type int Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type int by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getLong

    public long getLong(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance field of type long or of another primitive type convertible to type long via a widening conversion.

    Parameters: obj - the object to extract the long value from Returns: the value of the field converted to type long Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type long by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getFloat

    public float getFloat(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance field of type float or of another primitive type convertible to type float via a widening conversion.

    Parameters: obj - the object to extract the float value from Returns: the value of the field converted to type float Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type float by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • getDouble

    public double getDouble(Object obj) throws IllegalArgumentException, IllegalAccessException

    Gets the value of a static or instance field of type double or of another primitive type convertible to type double via a widening conversion.

    Parameters: obj - the object to extract the double value from Returns: the value of the field converted to type double Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if the field value cannot be converted to the type double by a widening conversion. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • get(Object)

  • set

    public void set(Object obj, Object value) throws IllegalArgumentException, IllegalAccessException

    Sets the field represented by this Field object on the specified object argument to the specified new value. The new value is automatically unwrapped if the underlying field has a primitive type.

    The operation proceeds as follows:

    If the underlying field is static, the obj argument is ignored; it may be null.

    Otherwise the underlying field is an instance field. If the specified object argument is null, the method throws a NullPointerException. If the specified object argument is not an instance of the class or interface declaring the underlying field, the method throws an IllegalArgumentException.

    If this Field object is enforcing Java language access control, and the underlying field is inaccessible, the method throws an IllegalAccessException.

    If the underlying field is final, this Field object has write access if and only if all of the following conditions are true, where D is the field's declaring class:

    • setAccessible(true) has succeeded for this Field object.
    • final field mutation is enabled for the caller's module.
    • At least one of the following conditions holds:
      1. D and the caller class are in the same module.
      2. The field is public and D is public in a package that the module containing D exports to at least the caller's module.
      3. D is in a package that is open to the caller's module.
    • D is not a record class.
    • D is not a hidden class.
    • The field is non-static.

    If any of the above conditions is not met, this method throws an IllegalAccessException.

    These conditions are more restrictive than the conditions specified by setAccessible(boolean) to suppress access checks. In particular, updating a module to export or open a package cannot be used to allow write access to final fields with the set methods defined by Field. Condition (b) is not met if the module containing D has been updated with addExports to export the package to the caller's module. Condition (c) is not met if the module containing D has been updated with addOpens to open the package to the caller's module.

    This method may be called by JNI code with no caller class on the stack. In that case, and when the underlying field is final, this Field object has write access if and only if all of the following conditions are true, where D is the field's declaring class:

    • setAccessible(true) has succeeded for this Field object.
    • final field mutation is enabled for the unnamed module.
    • The field is public and D is public in a package that is exported to all modules.
    • D is not a record class.
    • D is not a hidden class.
    • The field is non-static.

    If any of the above conditions is not met, this method throws an IllegalAccessException.

    Setting a final field in this way is meaningful only during deserialization or reconstruction of instances of classes with blank final fields, before they are made available for access by other parts of a program. Use in any other context may have unpredictable effects, including cases in which other parts of a program continue to use the original value of this field.

    If the underlying field is of a primitive type, an unwrapping conversion is attempted to convert the new value to a value of a primitive type. If this attempt fails, the method throws an IllegalArgumentException.

    If, after possible unwrapping, the new value cannot be converted to the type of the underlying field by an identity or widening conversion, the method throws an IllegalArgumentException.

    If the underlying field is static, the class that declared the field is initialized if it has not already been initialized.

    The field is set to the possibly unwrapped and widened new value.

    If the field is hidden in the type of obj, the field's value is set according to the preceding rules.

    Parameters: obj - the object whose field should be modified value - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • Mutation methods

  • setBoolean

    public void setBoolean(Object obj, boolean z) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a boolean on the specified object. This method is equivalent to set(obj, zObj), where zObj is a Boolean object and zObj.booleanValue() == z.

    Parameters: obj - the object whose field should be modified z - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setByte

    public void setByte(Object obj, byte b) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a byte on the specified object. This method is equivalent to set(obj, bObj), where bObj is a Byte object and bObj.byteValue() == b.

    Parameters: obj - the object whose field should be modified b - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setChar

    public void setChar(Object obj, char c) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a char on the specified object. This method is equivalent to set(obj, cObj), where cObj is a Character object and cObj.charValue() == c.

    Parameters: obj - the object whose field should be modified c - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setShort

    public void setShort(Object obj, short s) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a short on the specified object. This method is equivalent to set(obj, sObj), where sObj is a Short object and sObj.shortValue() == s.

    Parameters: obj - the object whose field should be modified s - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setInt

    public void setInt(Object obj, int i) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as an int on the specified object. This method is equivalent to set(obj, iObj), where iObj is an Integer object and iObj.intValue() == i.

    Parameters: obj - the object whose field should be modified i - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setLong

    public void setLong(Object obj, long l) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a long on the specified object. This method is equivalent to set(obj, lObj), where lObj is a Long object and lObj.longValue() == l.

    Parameters: obj - the object whose field should be modified l - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setFloat

    public void setFloat(Object obj, float f) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a float on the specified object. This method is equivalent to set(obj, fObj), where fObj is a Float object and fObj.floatValue() == f.

    Parameters: obj - the object whose field should be modified f - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • setDouble

    public void setDouble(Object obj, double d) throws IllegalArgumentException, IllegalAccessException

    Sets the value of a field as a double on the specified object. This method is equivalent to set(obj, dObj), where dObj is a Double object and dObj.doubleValue() == d.

    Parameters: obj - the object whose field should be modified d - the new value for the field of obj being modified Throws: IllegalAccessException - if this Field object is enforcing Java language access control and the underlying field is either inaccessible or final; or if this Field object has no write access. IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), or if an unwrapping conversion fails. NullPointerException - if the specified object is null and the field is an instance field. ExceptionInInitializerError - if the initialization provoked by this method fails. See Also:

    • set(Object, Object)

  • 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 AccessibleObject 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

  • getAnnotationsByType

    public <T extends Annotation> T[] getAnnotationsByType(Class<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) 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.

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

    Specified by: getAnnotationsByType in interface AnnotatedElement Overrides: getAnnotationsByType in class AccessibleObject 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 - if the given annotation class is null Since: 1.8

  • getAnnotatedType

    public AnnotatedType getAnnotatedType()

    Returns an AnnotatedType object that represents the use of a type to specify the declared type of the field represented by this Field.

    Returns: an object representing the declared type of the field represented by this Field Since: 1.8

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