Class Executable
- java.lang.Object
-
- java.lang.reflect.AccessibleObject
-
- java.lang.reflect.Executable
- All Implemented Interfaces:
-
AnnotatedElement
,GenericDeclaration
,Member
- Direct Known Subclasses:
-
Constructor
,Method
public abstract class Executable extends AccessibleObject implements Member, GenericDeclaration
A shared superclass for the common functionality of Method
and Constructor
.
- Since:
- 1.8
Field Summary
Fields declared in interface java.lang.reflect.Member
DECLARED, PUBLIC
Method Summary
Modifier and Type | Method | Description |
---|---|---|
AnnotatedType[] | getAnnotatedExceptionTypes() | Returns an array of |
AnnotatedType[] | getAnnotatedParameterTypes() | Returns an array of |
AnnotatedType | getAnnotatedReceiverType() | Returns an |
abstract AnnotatedType | getAnnotatedReturnType() | Returns an |
<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. |
abstract Class<?> | getDeclaringClass() | Returns the |
abstract Class<?>[] | getExceptionTypes() | Returns an array of |
Type[] | getGenericExceptionTypes() | Returns an array of |
Type[] | getGenericParameterTypes() | Returns an array of |
abstract int | getModifiers() | Returns the Java language modifiers 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 |
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 |
abstract Class<?>[] | getParameterTypes() | Returns an array of |
abstract TypeVariable<?>[] | getTypeParameters() | Returns an array of |
boolean | isSynthetic() | Returns |
boolean | isVarArgs() | Returns |
abstract String | toGenericString() | Returns a string describing this |
Methods declared in class java.lang.reflect.AccessibleObject
canAccess, getAnnotations, getDeclaredAnnotation, getDeclaredAnnotations, getDeclaredAnnotationsByType, isAccessible, isAnnotationPresent, setAccessible, setAccessible, trySetAccessible
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods declared in interface java.lang.reflect.AnnotatedElement
getAnnotations, getDeclaredAnnotation, getDeclaredAnnotations, getDeclaredAnnotationsByType, isAnnotationPresent
Method Detail
getDeclaringClass
public abstract Class<?> getDeclaringClass()
Returns the Class
object representing the class or interface that declares the executable represented by this object.
- Specified by:
-
getDeclaringClass
in interfaceMember
- Returns:
- an object representing the declaring class of the underlying member
getName
public abstract String getName()
Returns the name of the executable represented by this object.
getModifiers
public abstract int getModifiers()
Returns the Java language modifiers for the executable represented by this object.
- Specified by:
-
getModifiers
in interfaceMember
- Returns:
- the Java language modifiers for the underlying member
- See Also:
Modifier
getTypeParameters
public 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. Returns an array of length 0 if the underlying generic declaration declares no type variables.
- Specified by:
-
getTypeParameters
in interfaceGenericDeclaration
- Returns:
- an array of
TypeVariable
objects that represent the type variables declared by this generic declaration - Throws:
-
GenericSignatureFormatError
- if the generic signature of this generic declaration does not conform to the format specified in The Java™ Virtual Machine Specification
getParameterTypes
public 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. Returns an array of length 0 if the underlying executable takes no parameters.
- Returns:
- the parameter types for the executable this object represents
getParameterCount
public int getParameterCount()
Returns the number of formal parameters (whether explicitly declared or implicitly declared or neither) for the executable represented by this object.
- Returns:
- The number of formal parameters for the executable this object represents
getGenericParameterTypes
public Type[] getGenericParameterTypes()
Returns an array of Type
objects that represent the formal parameter types, in declaration order, of the executable represented by this object. 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.
- Returns:
- an array of
Type
s that represent the formal parameter types of the underlying executable, in declaration order - Throws:
-
GenericSignatureFormatError
- if the generic method signature does not conform to the format specified in The Java™ Virtual Machine Specification -
TypeNotPresentException
- if any of the parameter types of the underlying executable refers to a non-existent type declaration -
MalformedParameterizedTypeException
- if any of the underlying executable's parameter types refer to a parameterized type that cannot be instantiated for any reason
getParameters
public Parameter[] getParameters()
Returns an array of 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).
- Returns:
- an array of
Parameter
objects representing all the parameters to the executable this object represents. - Throws:
-
MalformedParametersException
- if the class file contains a MethodParameters attribute that is improperly formatted.
getExceptionTypes
public 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. Returns an array of length 0 if the executable declares no exceptions in its
throws
clause.
- Returns:
- the exception types declared as being thrown by the executable this object represents
getGenericExceptionTypes
public Type[] getGenericExceptionTypes()
Returns an array of Type
objects that represent the exceptions declared to be thrown by this executable object. Returns an array of length 0 if the underlying executable declares no exceptions in its throws
clause.
If an exception type is a type variable or a parameterized type, it is created. Otherwise, it is resolved.
- Returns:
- an array of Types that represent the exception types thrown by the underlying executable
- Throws:
-
GenericSignatureFormatError
- if the generic method signature does not conform to the format specified in The Java™ Virtual Machine Specification -
TypeNotPresentException
- if the underlying executable'sthrows
clause refers to a non-existent type declaration -
MalformedParameterizedTypeException
- if the underlying executable'sthrows
clause refers to a parameterized type that cannot be instantiated for any reason
toGenericString
public abstract String toGenericString()
Returns a string describing this Executable
, including any type parameters.
- Returns:
- a string describing this
Executable
, including any type parameters
isVarArgs
public boolean isVarArgs()
Returns true
if this executable was declared to take a variable number of arguments; returns false
otherwise.
- Returns:
-
true
if an only if this executable was declared to take a variable number of arguments.
isSynthetic
public boolean isSynthetic()
Returns true
if this executable is a synthetic construct; returns false
otherwise.
- Specified by:
-
isSynthetic
in interfaceMember
- Returns:
- true if and only if this executable is a synthetic construct as defined by The Java™ Language Specification.
getParameterAnnotations
public abstract Annotation[][] getParameterAnnotations()
Returns an array of arrays of Annotation
s 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.
- Returns:
- an array of arrays that represent the annotations on the formal and implicit parameters, in declaration order, of the executable represented by this object
- See Also:
-
Parameter
,AnnotatedElement.getAnnotations()
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.
- Specified by:
-
getAnnotation
in interfaceAnnotatedElement
- Overrides:
-
getAnnotation
in 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
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 interfaceAnnotatedElement
- Overrides:
-
getAnnotationsByType
in 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
getAnnotatedReturnType
public abstract AnnotatedType getAnnotatedReturnType()
Returns an AnnotatedType
object that represents the use of a type to specify the return type of the method/constructor represented by this Executable. If this Executable
object represents a constructor, the
AnnotatedType
object represents the type of the constructed object. If this Executable
object represents a method, the
AnnotatedType
object represents the use of a type to specify the return type of the method.
- Returns:
- an object representing the return type of the method or constructor represented by this
Executable
getAnnotatedReceiverType
public AnnotatedType getAnnotatedReceiverType()
Returns an AnnotatedType
object that represents the use of a type to specify the receiver type of the method/constructor represented by this Executable
object. The receiver type of a method/constructor is available only if the method/constructor has a receiver parameter (JLS 8.4.1). If this
Executable
object represents an instance method or represents a constructor of an inner member class, and the method/constructor either has no receiver parameter or has a receiver parameter with no annotations on its type, then the return value is an AnnotatedType
object representing an element with no annotations. If this Executable
object represents a static method or represents a constructor of a top level, static member, local, or anonymous class, then the return value is null.
- Returns:
- an object representing the receiver type of the method or constructor represented by this
Executable
ornull
if thisExecutable
can not have a receiver parameter
getAnnotatedParameterTypes
public AnnotatedType[] getAnnotatedParameterTypes()
Returns an array of AnnotatedType
objects that represent the use of types to specify formal parameter types of the method/constructor represented by this Executable. The order of the objects in the array corresponds to the order of the formal parameter types in the declaration of the method/constructor. Returns an array of length 0 if the method/constructor declares no parameters.
- Returns:
- an array of objects representing the types of the formal parameters of the method or constructor represented by this
Executable
getAnnotatedExceptionTypes
public AnnotatedType[] getAnnotatedExceptionTypes()
Returns an array of AnnotatedType
objects that represent the use of types to specify the declared exceptions of the method/constructor represented by this Executable. The order of the objects in the array corresponds to the order of the exception types in the declaration of the method/constructor. Returns an array of length 0 if the method/constructor declares no exceptions.
- Returns:
- an array of objects representing the declared exceptions of the method or constructor represented by this
Executable