- java.lang.Object
-
- java.lang.reflect.AccessibleObject
-
- java.lang.reflect.Field
-
- All Implemented Interfaces:
AnnotatedElement,Member
public final class Field extends AccessibleObject implements Member
AFieldprovides 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
Fieldpermits widening conversions to occur during a get or set access operation, but throws anIllegalArgumentExceptionif a narrowing conversion would occur.- Since:
- 1.1
- See Also:
Member,Class,Class.getFields(),Class.getField(String),Class.getDeclaredFields(),Class.getDeclaredField(String)
-
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description booleanequals(Object obj)Compares thisFieldagainst the specified object.Objectget(Object obj)Returns the value of the field represented by thisField, on the specified object.AnnotatedTypegetAnnotatedType()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>
TgetAnnotation(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.booleangetBoolean(Object obj)Gets the value of a static or instancebooleanfield.bytegetByte(Object obj)Gets the value of a static or instancebytefield.chargetChar(Object obj)Gets the value of a static or instance field of typecharor of another primitive type convertible to typecharvia a widening conversion.Class<?>getDeclaringClass()Returns theClassobject representing the class or interface that declares the field represented by thisFieldobject.doublegetDouble(Object obj)Gets the value of a static or instance field of typedoubleor of another primitive type convertible to typedoublevia a widening conversion.floatgetFloat(Object obj)Gets the value of a static or instance field of typefloator of another primitive type convertible to typefloatvia a widening conversion.TypegetGenericType()Returns aTypeobject that represents the declared type for the field represented by thisFieldobject.intgetInt(Object obj)Gets the value of a static or instance field of typeintor of another primitive type convertible to typeintvia a widening conversion.longgetLong(Object obj)Gets the value of a static or instance field of typelongor of another primitive type convertible to typelongvia a widening conversion.intgetModifiers()Returns the Java language modifiers for the field represented by thisFieldobject, as an integer.StringgetName()Returns the name of the field represented by thisFieldobject.shortgetShort(Object obj)Gets the value of a static or instance field of typeshortor of another primitive type convertible to typeshortvia a widening conversion.Class<?>getType()Returns aClassobject that identifies the declared type for the field represented by thisFieldobject.inthashCode()Returns a hashcode for thisField.booleanisEnumConstant()Returnstrueif this field represents an element of an enumerated type; returnsfalseotherwise.booleanisSynthetic()Returnstrueif this field is a synthetic field; returnsfalseotherwise.voidset(Object obj, Object value)Sets the field represented by thisFieldobject on the specified object argument to the specified new value.voidsetAccessible(boolean flag)Set theaccessibleflag for this reflected object to the indicated boolean value.voidsetBoolean(Object obj, boolean z)Sets the value of a field as abooleanon the specified object.voidsetByte(Object obj, byte b)Sets the value of a field as abyteon the specified object.voidsetChar(Object obj, char c)Sets the value of a field as acharon the specified object.voidsetDouble(Object obj, double d)Sets the value of a field as adoubleon the specified object.voidsetFloat(Object obj, float f)Sets the value of a field as afloaton the specified object.voidsetInt(Object obj, int i)Sets the value of a field as aninton the specified object.voidsetLong(Object obj, long l)Sets the value of a field as alongon the specified object.voidsetShort(Object obj, short s)Sets the value of a field as ashorton the specified object.StringtoGenericString()Returns a string describing thisField, including its generic type.StringtoString()Returns a string describing thisField.-
Methods declared in class java.lang.reflect.AccessibleObject
canAccess, getAnnotations, getDeclaredAnnotation, getDeclaredAnnotations, getDeclaredAnnotationsByType, isAccessible, isAnnotationPresent, setAccessible, trySetAccessible
-
-
-
-
Method Detail
-
setAccessible
public void setAccessible(boolean flag)
Description copied from class:AccessibleObjectSet theaccessibleflag for this reflected object to the indicated boolean value. A value oftrueindicates that the reflected object should suppress checks for Java language access control when it is used. A value offalseindicates 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
Cto enable access to amemberofdeclaring classDif any of the following hold:-
CandDare in the same module. - The member is
publicandDispublicin a package that the module containingDexportsto at least the module containingC. - The member is
protectedstatic,Dispublicin a package that the module containingDexports to at least the module containingC, andCis a subclass ofD. -
Dis in a package that the module containingDopensto at least the module containingC. All packages in unnamed and open modules are open to all modules and so this method always succeeds whenDis in an unnamed or open module.
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 there is a security manager, its
checkPermissionmethod is first called with aReflectPermission("suppressAccessChecks")permission.- Overrides:
setAccessiblein classAccessibleObject- Parameters:
flag- the new value for theaccessibleflag- Throws:
InaccessibleObjectException- if access cannot be enabledSecurityException- if the request is denied by the security manager- See Also:
AccessibleObject.trySetAccessible(),MethodHandles.privateLookupIn(java.lang.Class<?>, java.lang.invoke.MethodHandles.Lookup)
-
-
getDeclaringClass
public Class<?> getDeclaringClass()
Returns theClassobject representing the class or interface that declares the field represented by thisFieldobject.- Specified by:
getDeclaringClassin interfaceMember- Returns:
- an object representing the declaring class of the underlying member
-
getName
public String getName()
Returns the name of the field represented by thisFieldobject.
-
getModifiers
public int getModifiers()
Returns the Java language modifiers for the field represented by thisFieldobject, as an integer. TheModifierclass should be used to decode the modifiers.- Specified by:
getModifiersin interfaceMember- Returns:
- the Java language modifiers for the underlying member
- See Also:
Modifier
-
isEnumConstant
public boolean isEnumConstant()
Returnstrueif this field represents an element of an enumerated type; returnsfalseotherwise.- Returns:
trueif and only if this field represents an element of an enumerated type.- Since:
- 1.5
-
isSynthetic
public boolean isSynthetic()
Returnstrueif this field is a synthetic field; returnsfalseotherwise.- Specified by:
isSyntheticin interfaceMember- 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 aClassobject that identifies the declared type for the field represented by thisFieldobject.- Returns:
- a
Classobject identifying the declared type of the field represented by this object
-
getGenericType
public Type getGenericType()
Returns aTypeobject that represents the declared type for the field represented by thisFieldobject.If the
Typeis a parameterized type, theTypeobject 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
Typeobject that represents the declared type for the field represented by thisFieldobject - Throws:
GenericSignatureFormatError- if the generic field signature does not conform to the format specified in The Java™ Virtual Machine SpecificationTypeNotPresentException- if the generic type signature of the underlying field refers to a non-existent type declarationMalformedParameterizedTypeException- 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 thisFieldagainst the specified object. Returns true if the objects are the same. TwoFieldobjects are the same if they were declared by the same class and have the same name and type.- Overrides:
equalsin classObject- Parameters:
obj- the reference object with which to compare.- Returns:
trueif this object is the same as the obj argument;falseotherwise.- See Also:
Object.hashCode(),HashMap
-
hashCode
public int hashCode()
Returns a hashcode for thisField. This is computed as the exclusive-or of the hashcodes for the underlying field's declaring class name and its name.- Overrides:
hashCodein classObject- 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 thisField. 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.fdThe modifiers are placed in canonical order as specified by "The Java Language Specification". This is
public,protectedorprivatefirst, and then other modifiers in the following order:static,final,transient,volatile.
-
toGenericString
public String toGenericString()
Returns a string describing thisField, 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,protectedorprivatefirst, 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 thisField, 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
objargument is ignored; it may be null.Otherwise, the underlying field is an instance field. If the specified
objargument is null, the method throws aNullPointerException. If the specified object is not an instance of the class or interface declaring the underlying field, the method throws anIllegalArgumentException.If this
Fieldobject is enforcing Java language access control, and the underlying field is inaccessible, the method throws anIllegalAccessException. 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 thisFieldobject 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 instancebooleanfield.- Parameters:
obj- the object to extract thebooleanvalue from- Returns:
- the value of the
booleanfield - Throws:
IllegalAccessException- if thisFieldobject 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 typebooleanby 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 instancebytefield.- Parameters:
obj- the object to extract thebytevalue from- Returns:
- the value of the
bytefield - Throws:
IllegalAccessException- if thisFieldobject 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 typebyteby 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 typecharor of another primitive type convertible to typecharvia a widening conversion.- Parameters:
obj- the object to extract thecharvalue from- Returns:
- the value of the field converted to type
char - Throws:
IllegalAccessException- if thisFieldobject 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 typecharby 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 typeshortor of another primitive type convertible to typeshortvia a widening conversion.- Parameters:
obj- the object to extract theshortvalue from- Returns:
- the value of the field converted to type
short - Throws:
IllegalAccessException- if thisFieldobject 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 typeshortby 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 typeintor of another primitive type convertible to typeintvia a widening conversion.- Parameters:
obj- the object to extract theintvalue from- Returns:
- the value of the field converted to type
int - Throws:
IllegalAccessException- if thisFieldobject 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 typeintby 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 typelongor of another primitive type convertible to typelongvia a widening conversion.- Parameters:
obj- the object to extract thelongvalue from- Returns:
- the value of the field converted to type
long - Throws:
IllegalAccessException- if thisFieldobject 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 typelongby 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 typefloator of another primitive type convertible to typefloatvia a widening conversion.- Parameters:
obj- the object to extract thefloatvalue from- Returns:
- the value of the field converted to type
float - Throws:
IllegalAccessException- if thisFieldobject 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 typefloatby 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 typedoubleor of another primitive type convertible to typedoublevia a widening conversion.- Parameters:
obj- the object to extract thedoublevalue from- Returns:
- the value of the field converted to type
double - Throws:
IllegalAccessException- if thisFieldobject 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 typedoubleby 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 thisFieldobject 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
objargument 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 anIllegalArgumentException.If this
Fieldobject is enforcing Java language access control, and the underlying field is inaccessible, the method throws anIllegalAccessException.If the underlying field is final, the method throws an
IllegalAccessExceptionunlesssetAccessible(true)has succeeded for thisFieldobject 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 modifiedvalue- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 abooleanon the specified object. This method is equivalent toset(obj, zObj), wherezObjis aBooleanobject andzObj.booleanValue() == z.- Parameters:
obj- the object whose field should be modifiedz- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 abyteon the specified object. This method is equivalent toset(obj, bObj), wherebObjis aByteobject andbObj.byteValue() == b.- Parameters:
obj- the object whose field should be modifiedb- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 acharon the specified object. This method is equivalent toset(obj, cObj), wherecObjis aCharacterobject andcObj.charValue() == c.- Parameters:
obj- the object whose field should be modifiedc- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 ashorton the specified object. This method is equivalent toset(obj, sObj), wheresObjis aShortobject andsObj.shortValue() == s.- Parameters:
obj- the object whose field should be modifieds- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 aninton the specified object. This method is equivalent toset(obj, iObj), whereiObjis anIntegerobject andiObj.intValue() == i.- Parameters:
obj- the object whose field should be modifiedi- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 alongon the specified object. This method is equivalent toset(obj, lObj), wherelObjis aLongobject andlObj.longValue() == l.- Parameters:
obj- the object whose field should be modifiedl- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 afloaton the specified object. This method is equivalent toset(obj, fObj), wherefObjis aFloatobject andfObj.floatValue() == f.- Parameters:
obj- the object whose field should be modifiedf- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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 adoubleon the specified object. This method is equivalent toset(obj, dObj), wheredObjis aDoubleobject anddObj.doubleValue() == d.- Parameters:
obj- the object whose field should be modifiedd- the new value for the field ofobjbeing modified- Throws:
IllegalAccessException- if thisFieldobject 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:AnnotatedElementReturns this element's annotation for the specified type if such an annotation is present, else null.- Specified by:
getAnnotationin interfaceAnnotatedElement- Overrides:
getAnnotationin classAccessibleObject- 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 andAnnotatedElement.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:
getAnnotationsByTypein interfaceAnnotatedElement- Overrides:
getAnnotationsByTypein classAccessibleObject- 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
-
-