javax.lang.model.element.Element Maven / Gradle / Ivy
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package javax.lang.model.element;
import java.lang.annotation.Annotation;
import java.lang.annotation.AnnotationTypeMismatchException;
import java.lang.annotation.IncompleteAnnotationException;
import java.util.List;
import java.util.Set;
import javax.lang.model.type.*;
import javax.lang.model.util.*;
/**
* Represents a program element such as a module, package, class, or method.
* Each element represents a static, language-level construct
* (and not, for example, a runtime construct of the virtual machine).
*
* Elements should be compared using the {@link #equals(Object)}
* method. There is no guarantee that any particular element will
* always be represented by the same object.
*
*
To implement operations based on the class of an {@code
* Element} object, either use a {@linkplain ElementVisitor visitor} or
* use the result of the {@link #getKind} method. Using {@code
* instanceof} is not necessarily a reliable idiom for
* determining the effective class of an object in this modeling
* hierarchy since an implementation may choose to have a single object
* implement multiple {@code Element} subinterfaces.
*
* @author Joseph D. Darcy
* @author Scott Seligman
* @author Peter von der Ahé
* @see Elements
* @see TypeMirror
* @since 1.6
*/
public interface Element extends javax.lang.model.AnnotatedConstruct {
/**
* Returns the type defined by this element.
*
*
A generic element defines a family of types, not just one.
* If this is a generic element, a prototypical type is
* returned. This is the element's invocation on the
* type variables corresponding to its own formal type parameters.
* For example,
* for the generic class element {@code C},
* the parameterized type {@code C} is returned.
* The {@link Types} utility interface has more general methods
* for obtaining the full range of types defined by an element.
*
* @see Types
*
* @return the type defined by this element
*/
TypeMirror asType();
/**
* Returns the {@code kind} of this element.
*
* @return the kind of this element
*/
ElementKind getKind();
/**
* Returns the modifiers of this element, excluding annotations.
* Implicit modifiers, such as the {@code public} and {@code static}
* modifiers of interface members, are included.
*
* @return the modifiers of this element, or an empty set if there are none
*/
Set getModifiers();
/**
* Returns the simple (unqualified) name of this element. The
* name of a generic type does not include any reference to its
* formal type parameters.
*
* For example, the simple name of the type element {@code
* java.util.Set} is {@code "Set"}.
*
* If this element represents an unnamed {@linkplain
* PackageElement#getSimpleName package} or unnamed {@linkplain
* ModuleElement#getSimpleName module}, an empty name is returned.
*
* If it represents a {@linkplain ExecutableElement#getSimpleName
* constructor}, the name "{@code }" is returned. If it
* represents a {@linkplain ExecutableElement#getSimpleName static
* initializer}, the name "{@code }" is returned.
*
* If it represents an {@linkplain TypeElement#getSimpleName
* anonymous class} or {@linkplain ExecutableElement#getSimpleName
* instance initializer}, an empty name is returned.
*
* @return the simple name of this element
* @see PackageElement#getSimpleName
* @see ExecutableElement#getSimpleName
* @see TypeElement#getSimpleName
* @see VariableElement#getSimpleName
* @see ModuleElement#getSimpleName
* @revised 9
* @spec JPMS
*/
Name getSimpleName();
/**
* Returns the innermost element
* within which this element is, loosely speaking, enclosed.
*
* - If this element is one whose declaration is lexically enclosed
* immediately within the declaration of another element, that other
* element is returned.
*
*
- If this is a {@linkplain TypeElement#getEnclosingElement
* top-level type}, its package is returned.
*
*
- If this is a {@linkplain
* PackageElement#getEnclosingElement package}, its module is
* returned if such a module exists. Otherwise, {@code null} is returned.
*
*
- If this is a {@linkplain
* TypeParameterElement#getEnclosingElement type parameter},
* {@linkplain TypeParameterElement#getGenericElement the
* generic element} of the type parameter is returned.
*
*
- If this is a {@linkplain
* VariableElement#getEnclosingElement method or constructor
* parameter}, {@linkplain ExecutableElement the executable
* element} which declares the parameter is returned.
*
*
- If this is a {@linkplain ModuleElement#getEnclosingElement
* module}, {@code null} is returned.
*
*
*
* @return the enclosing element, or {@code null} if there is none
* @see Elements#getPackageOf
* @revised 9
* @spec JPMS
*/
Element getEnclosingElement();
/**
* Returns the elements that are, loosely speaking, directly
* enclosed by this element.
*
* A {@linkplain TypeElement#getEnclosedElements class or
* interface} is considered to enclose the fields, methods,
* constructors, and member types that it directly declares.
*
* A {@linkplain PackageElement#getEnclosedElements package}
* encloses the top-level classes and interfaces within it, but is
* not considered to enclose subpackages.
*
* A {@linkplain ModuleElement#getEnclosedElements module}
* encloses packages within it.
*
* Enclosed elements may include implicitly declared {@linkplain
* Elements.Origin#MANDATED mandated} elements.
*
* Other kinds of elements are not currently considered to enclose
* any elements; however, that may change as this API or the
* programming language evolves.
*
* @apiNote Elements of certain kinds can be isolated using
* methods in {@link ElementFilter}.
*
* @return the enclosed elements, or an empty list if none
* @see TypeElement#getEnclosedElements
* @see PackageElement#getEnclosedElements
* @see ModuleElement#getEnclosedElements
* @see Elements#getAllMembers
* @jls 8.8.9 Default Constructor
* @jls 8.9 Enums
* @revised 9
* @spec JPMS
*/
List getEnclosedElements();
/**
* Returns {@code true} if the argument represents the same
* element as {@code this}, or {@code false} otherwise.
*
* @apiNote The identity of an element involves implicit state
* not directly accessible from the element's methods, including
* state about the presence of unrelated types. Element objects
* created by different implementations of these interfaces should
* not be expected to be equal even if "the same"
* element is being modeled; this is analogous to the inequality
* of {@code Class} objects for the same class file loaded through
* different class loaders.
*
* @param obj the object to be compared with this element
* @return {@code true} if the specified object represents the same
* element as this
*/
@Override
boolean equals(Object obj);
/**
* Obeys the general contract of {@link Object#hashCode Object.hashCode}.
*
* @see #equals
*/
@Override
int hashCode();
/**
* {@inheritDoc}
*
* To get inherited annotations as well, use {@link
* Elements#getAllAnnotationMirrors(Element)
* getAllAnnotationMirrors}.
*
* @since 1.6
*/
@Override
List getAnnotationMirrors();
/**
* {@inheritDoc}
* @since 1.6
*/
@Override
A getAnnotation(Class annotationType);
/**
* Applies a visitor to this element.
*
* @param the return type of the visitor's methods
* @param the type of the additional parameter to the visitor's methods
* @param v the visitor operating on this element
* @param p additional parameter to the visitor
* @return a visitor-specified result
*/
R accept(ElementVisitor v, P p);
}