Field (Java Platform SE 8 )

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

All Implemented Interfaces:

AnnotatedElement, Member
```
public final class Field
extends AccessibleObject
implements Member
```
A Field provides information about, and dynamic access to, a single field of a class or an interface. The reflected field may be a class (static) field or an instance field.
A Field permits widening conversions to occur during a get or set access operation, but throws an IllegalArgumentException if a narrowing conversion would occur.

See Also:

Member, Class, Class.getFields(), Class.getField(String), Class.getDeclaredFields(), Class.getDeclaredField(String)

Field Summary
- Fields inherited from interface java.lang.reflect.Member
  DECLARED, PUBLIC

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`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.
`Annotation[]`	`getDeclaredAnnotations()` Returns annotations that are directly present on this element.
`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 type; 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`	`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 inherited from class java.lang.reflect.AccessibleObject
getAnnotations, getDeclaredAnnotation, getDeclaredAnnotationsByType, isAccessible, isAnnotationPresent, setAccessible, setAccessible

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Method Detail
  - 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 Also:
    
    Modifier
  - isEnumConstant
```
public boolean isEnumConstant()
```
    Returns true if this field represents an element of an enumerated type; returns false otherwise.
    
    Returns:
    
    true if and only if this field represents an element of an enumerated type.
    
    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
  - 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 Type is a parameterized type, the Type object returned must accurately reflect the actual type parameters 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 type 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(java.lang.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 The 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
    
    Since:
    
    1.5
    
    See The Java™ Language Specification:
    
    8.3.1 Field Modifiers
  - 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(java.lang.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(java.lang.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(java.lang.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(java.lang.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(java.lang.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(java.lang.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(java.lang.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(java.lang.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, the method throws an IllegalAccessException unless setAccessible(true) has succeeded for this Field object and the field is non-static. 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 either inaccessible or final.
    
    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.
  - 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.
    
    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(java.lang.Object, java.lang.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.
    
    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(java.lang.Object, java.lang.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.
    
    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(java.lang.Object, java.lang.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.
    
    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(java.lang.Object, java.lang.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 a 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.
    
    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(java.lang.Object, java.lang.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.
    
    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(java.lang.Object, java.lang.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.
    
    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(java.lang.Object, java.lang.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.
    
    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(java.lang.Object, java.lang.Object)
  - getAnnotation
```
public <T extends Annotation> T getAnnotation(Class<T> annotationClass)
```
    Description copied from interface: AnnotatedElement
    
    Returns this element's annotation for the specified type if such an annotation is present, else null.
    
    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.
    
    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
  - 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.
    
    Specified by:
    
    getDeclaredAnnotations in interface AnnotatedElement
    
    Overrides:
    
    getDeclaredAnnotations in class AccessibleObject
    
    Returns:
    
    annotations directly present on this element
  - 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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Class Field

Field Summary

Fields inherited from interface java.lang.reflect.Member

Method Summary

Methods inherited from class java.lang.reflect.AccessibleObject

Methods inherited from class java.lang.Object

Method Detail

getDeclaringClass

getName

getModifiers

isEnumConstant

isSynthetic

getType

getGenericType

equals

hashCode

toString

toGenericString

get

getBoolean

getByte

getChar

getShort

getInt

getLong

getFloat

getDouble

set

setBoolean

setByte

setChar

setShort

setInt

setLong

setFloat

setDouble

getAnnotation

getAnnotationsByType

getDeclaredAnnotations

getAnnotatedType