AnnotatedElement, GenericDeclaration, MemberConstructor, Methodpublic abstract class Executable extends AccessibleObject implements Member, GenericDeclaration
Method
and Constructor.| 限定符和类型 | 方法 | 说明 |
|---|---|---|
<T extends Annotation> |
getAnnotation(Class<T> annotationClass) |
Returns this element's annotation for the specified type if
such an annotation is present, else null.
|
<T extends Annotation> |
getAnnotationsByType(Class<T> annotationClass) |
Returns annotations that are associated with this element.
|
Annotation[] |
getDeclaredAnnotations() |
Returns annotations that are directly present on this element.
|
abstract Class<?> |
getDeclaringClass() |
Returns the
Class object representing the class or interface
that declares the executable represented by this object. |
abstract Class<?>[] |
getExceptionTypes() |
Returns an array of
Class objects that represent the
types of exceptions declared to be thrown by the underlying
executable represented by this object. |
Type[] |
getGenericExceptionTypes() |
Returns an array of
Type objects that represent the
exceptions declared to be thrown by this executable object. |
Type[] |
getGenericParameterTypes() |
Returns an array of
Type objects that represent the formal
parameter types, in declaration order, of the executable represented by
this object. |
abstract int |
getModifiers() |
Returns the Java language Modifier for
the executable represented by this object.
|
abstract String |
getName() |
Returns the name of the executable represented by this object.
|
abstract Annotation[][] |
getParameterAnnotations() |
Returns an array of arrays of
Annotations that
represent the annotations on the formal parameters, in
declaration order, of the Executable represented by
this object. |
int |
getParameterCount() |
Returns the number of formal parameters (whether explicitly
declared or implicitly declared or neither) for the executable
represented by this object.
|
Parameter[] |
getParameters() |
Returns an array of
Parameter objects that represent
all the parameters to the underlying executable represented by
this object. |
abstract Class<?>[] |
getParameterTypes() |
Returns an array of
Class objects that represent the formal
parameter types, in declaration order, of the executable
represented by this object. |
abstract TypeVariable<?>[] |
getTypeParameters() |
Returns an array of
TypeVariable objects that represent the
type variables declared by the generic declaration represented by this
GenericDeclaration object, in declaration order. |
boolean |
isSynthetic() |
Returns
true if this executable is a synthetic
construct; returns false otherwise. |
boolean |
isVarArgs() |
Returns
true if this executable was declared to take a
variable number of arguments; returns false otherwise. |
abstract String |
toGenericString() |
Returns a string describing this
Executable, including
any type parameters. |
getAnnotations, getDeclaredAnnotation, getDeclaredAnnotationsByType, isAccessible, isAnnotationPresent, setAccessible, setAccessiblegetAnnotations, getDeclaredAnnotation, getDeclaredAnnotationsByType, isAnnotationPresentpublic abstract Class<?> getDeclaringClass()
Class object representing the class or interface
that declares the executable represented by this object.getDeclaringClass 在接口中 Memberpublic abstract String getName()
public abstract int getModifiers()
getModifiers 在接口中 MemberModifierpublic abstract TypeVariable<?>[] getTypeParameters()
TypeVariable objects that represent the
type variables declared by the generic declaration represented by this
GenericDeclaration object, in declaration order. Returns an
array of length 0 if the underlying generic declaration declares no type
variables.getTypeParameters 在接口中 GenericDeclarationTypeVariable objects that represent
the type variables declared by this generic declarationGenericSignatureFormatError - if the generic
signature of this generic declaration does not conform to
the format specified in
The Java™ Virtual Machine Specificationpublic abstract Class<?>[] getParameterTypes()
Class objects that represent the formal
parameter types, in declaration order, of the executable
represented by this object. Returns an array of length
0 if the underlying executable takes no parameters.public int getParameterCount()
public Type[] getGenericParameterTypes()
Type objects that represent the formal
parameter types, in declaration order, of the executable represented by
this object. Returns an array of length 0 if the
underlying executable takes no parameters.
If a formal parameter type is a parameterized type,
the Type object returned for it must accurately reflect
the actual type parameters used in the source code.
If a formal parameter type is a type variable or a parameterized type, it is created. Otherwise, it is resolved.
Types that represent the formal
parameter types of the underlying executable, in declaration orderGenericSignatureFormatError - if the generic method signature does not conform to the format
specified in
The Java™ Virtual Machine SpecificationTypeNotPresentException - if any of the parameter
types of the underlying executable refers to a non-existent type
declarationMalformedParameterizedTypeException - if any of
the underlying executable's parameter types refer to a parameterized
type that cannot be instantiated for any reasonpublic Parameter[] getParameters()
Parameter objects that represent
all the parameters to the underlying executable represented by
this object. Returns an array of length 0 if the executable
has no parameters.
The parameters of the underlying executable do not necessarily have unique names, or names that are legal identifiers in the Java programming language (JLS 3.8).
Parameter objects representing all
the parameters to the executable this object represents.MalformedParametersException - if the class file contains
a MethodParameters attribute that is improperly formatted.public abstract Class<?>[] getExceptionTypes()
Class objects that represent the
types of exceptions declared to be thrown by the underlying
executable represented by this object. Returns an array of
length 0 if the executable declares no exceptions in its
throws clause.public Type[] getGenericExceptionTypes()
Type objects that represent the
exceptions declared to be thrown by this executable object.
Returns an array of length 0 if the underlying executable declares
no exceptions in its throws clause.
If an exception type is a type variable or a parameterized type, it is created. Otherwise, it is resolved.
GenericSignatureFormatError - if the generic method signature does not conform to the format
specified in
The Java™ Virtual Machine SpecificationTypeNotPresentException - if the underlying executable's
throws clause refers to a non-existent type declarationMalformedParameterizedTypeException - if
the underlying executable's throws clause refers to a
parameterized type that cannot be instantiated for any reasonpublic abstract String toGenericString()
Executable, including
any type parameters.Executable, including
any type parameterspublic boolean isVarArgs()
true if this executable was declared to take a
variable number of arguments; returns false otherwise.true if an only if this executable was declared
to take a variable number of arguments.public boolean isSynthetic()
true if this executable is a synthetic
construct; returns false otherwise.isSynthetic 在接口中 Memberpublic abstract Annotation[][] getParameterAnnotations()
Annotations that
represent the annotations on the formal parameters, in
declaration order, of the Executable represented by
this object. Synthetic and mandated parameters (see
explanation below), such as the outer "this" parameter to an
inner class constructor will be represented in the returned
array. If the executable has no parameters (meaning no formal,
no synthetic, and no mandated parameters), a zero-length array
will be returned. If the Executable has one or more
parameters, a nested array of length zero is returned for each
parameter with no annotations. The annotation objects contained
in the returned arrays are serializable. The caller of this
method is free to modify the returned arrays; it will have no
effect on the arrays returned to other callers.
A compiler may add extra parameters that are implicitly
declared in source ("mandated"), as well as parameters that
are neither implicitly nor explicitly declared in source
("synthetic") to the parameter list for a method. See Parameter for more information.Parameter,
Parameter.getAnnotations()public <T extends Annotation> T getAnnotation(Class<T> annotationClass)
getAnnotation 在接口中 AnnotatedElementgetAnnotation 在类中 AccessibleObjectT - the type of the annotation to query for and return if presentannotationClass - the Class object corresponding to the
annotation typeNullPointerException - if the given annotation class is nullpublic <T extends Annotation> T[] getAnnotationsByType(Class<T> annotationClass)
AnnotatedElement.getAnnotation(java.lang.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.getAnnotationsByType 在接口中 AnnotatedElementgetAnnotationsByType 在类中 AccessibleObjectT - the type of the annotation to query for and return if presentannotationClass - the Class object corresponding to the
annotation typeNullPointerException - if the given annotation class is nullpublic Annotation[] getDeclaredAnnotations()
getDeclaredAnnotations 在接口中 AnnotatedElementgetDeclaredAnnotations 在类中 AccessibleObject