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public interface: Element [javadoc | source]

All Known Implementing Classes:
    PackageElement, TypeParameterElement, VariableElement, QualifiedNameable, Parameterizable, ExecutableElement, TypeElement

Represents a program element such as a 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 #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 #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.

Method from javax.lang.model.element.Element Summary:
accept,   asType,   equals,   getAnnotation,   getAnnotationMirrors,   getEnclosedElements,   getEnclosingElement,   getKind,   getModifiers,   getSimpleName,   hashCode
Method from javax.lang.model.element.Element Detail:
 public R accept(ElementVisitor<R, P> v,
    P p)
    Applies a visitor to this element.
 public TypeMirror asType()
    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 Types utility interface has more general methods for obtaining the full range of types defined by an element.

 public boolean equals(Object obj)
    Returns {@code true} if the argument represents the same element as {@code this}, or {@code false} otherwise.

    Note that 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.

 public A getAnnotation(Class<A> annotationType)
    Returns this element's annotation for the specified type if such an annotation is present, else {@code null}. The annotation may be either inherited or directly present on this element.

    The annotation returned by this method could contain an element whose value is of type {@code Class}. This value cannot be returned directly: information necessary to locate and load a class (such as the class loader to use) is not available, and the class might not be loadable at all. Attempting to read a {@code Class} object by invoking the relevant method on the returned annotation will result in a MirroredTypeException , from which the corresponding TypeMirror may be extracted. Similarly, attempting to read a {@code Class[]}-valued element will result in a MirroredTypesException .

    Note: This method is unlike others in this and related interfaces. It operates on runtime reflective information — representations of annotation types currently loaded into the VM — rather than on the representations defined by and used throughout these interfaces. Consequently, calling methods on the returned annotation object can throw many of the exceptions that can be thrown when calling methods on an annotation object returned by core reflection. This method is intended for callers that are written to operate on a known, fixed set of annotation types.
 public List<AnnotationMirror> getAnnotationMirrors()
    Returns the annotations that are directly present on this element.

    To get inherited annotations as well, use getAllAnnotationMirrors .

 public List<Element> getEnclosedElements()
    Returns the elements that are, loosely speaking, directly enclosed by this element. A class or interface is considered to enclose the fields, methods, constructors, and member types that it directly declares. This includes any (implicit) default constructor and the implicit {@code values} and {@code valueOf} methods of an enum type. A package encloses the top-level classes and interfaces within it, but is not considered to enclose subpackages. Other kinds of elements are not currently considered to enclose any elements; however, that may change as this API or the programming language evolves.

    Note that elements of certain kinds can be isolated using methods in ElementFilter .

 public Element getEnclosingElement()
    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}, {@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.
 public ElementKind getKind()
    Returns the {@code kind} of this element.
 public Set<Modifier> getModifiers()
    Returns the modifiers of this element, excluding annotations. Implicit modifiers, such as the {@code public} and {@code static} modifiers of interface members, are included.
 public Name getSimpleName()
    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}, 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.
 public int hashCode()