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package javax.lang.model.util;

import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.*;
import static javax.lang.model.SourceVersion.*;


A skeletal visitor of program elements with default behavior appropriate for the RELEASE_6 source version.

WARNING: The ElementVisitor interface implemented by this class may have methods added to it in the future to accommodate new, currently unknown, language structures added to future versions of the Java™ programming language. Therefore, methods whose names begin with "visit" may be added to this class in the future; to avoid incompatibilities, classes which extend this class should not declare any instance methods with names beginning with "visit".

When such a new visit method is added, the default implementation in this class will be to call the visitUnknown method. A new abstract element visitor class will also be introduced to correspond to the new language level; this visitor will have different default behavior for the visit method in question. When the new visitor is introduced, all or portions of this visitor may be deprecated.

Author:Joseph D. Darcy, Scott Seligman, Peter von der Ahé
Type parameters:
  • <R> – the return type of this visitor's methods. Use Void for visitors that do not need to return results.
  • <P> – the type of the additional parameter to this visitor's methods. Use Void for visitors that do not need an additional parameter.
See Also:
Since:1.6
/** * A skeletal visitor of program elements with default behavior * appropriate for the {@link SourceVersion#RELEASE_6 RELEASE_6} * source version. * * <p> <b>WARNING:</b> The {@code ElementVisitor} interface * implemented by this class may have methods added to it in the * future to accommodate new, currently unknown, language structures * added to future versions of the Java&trade; programming language. * Therefore, methods whose names begin with {@code "visit"} may be * added to this class in the future; to avoid incompatibilities, * classes which extend this class should not declare any instance * methods with names beginning with {@code "visit"}. * * <p>When such a new visit method is added, the default * implementation in this class will be to call the {@link * #visitUnknown visitUnknown} method. A new abstract element visitor * class will also be introduced to correspond to the new language * level; this visitor will have different default behavior for the * visit method in question. When the new visitor is introduced, all * or portions of this visitor may be deprecated. * * @param <R> the return type of this visitor's methods. Use {@link * Void} for visitors that do not need to return results. * @param <P> the type of the additional parameter to this visitor's * methods. Use {@code Void} for visitors that do not need an * additional parameter. * * @author Joseph D. Darcy * @author Scott Seligman * @author Peter von der Ah&eacute; * * @see AbstractElementVisitor7 * @see AbstractElementVisitor8 * @see AbstractElementVisitor9 * @since 1.6 */
@SupportedSourceVersion(RELEASE_6) public abstract class AbstractElementVisitor6<R, P> implements ElementVisitor<R, P> {
Constructor for concrete subclasses to call.
Deprecated:Release 6 is obsolete; update to a visitor for a newer release level.
/** * Constructor for concrete subclasses to call. * @deprecated Release 6 is obsolete; update to a visitor for a newer * release level. */
@Deprecated(since="9") protected AbstractElementVisitor6(){}
Visits any program element as if by passing itself to that element's accept method. The invocation v.visit(elem, p) is equivalent to elem.accept(v, p).
Params:
  • e – the element to visit
  • p – a visitor-specified parameter
Returns:a visitor-specified result
/** * Visits any program element as if by passing itself to that * element's {@link Element#accept accept} method. The invocation * {@code v.visit(elem, p)} is equivalent to {@code elem.accept(v, * p)}. * * @param e the element to visit * @param p a visitor-specified parameter * @return a visitor-specified result */
public final R visit(Element e, P p) { return e.accept(this, p); }
Visits any program element as if by passing itself to that element's accept method and passing null for the additional parameter. The invocation v.visit(elem) is equivalent to elem.accept(v, null).
Params:
  • e – the element to visit
Returns:a visitor-specified result
/** * Visits any program element as if by passing itself to that * element's {@link Element#accept accept} method and passing * {@code null} for the additional parameter. The invocation * {@code v.visit(elem)} is equivalent to {@code elem.accept(v, * null)}. * * @param e the element to visit * @return a visitor-specified result */
public final R visit(Element e) { return e.accept(this, null); }
{@inheritDoc}
Params:
  • e – {@inheritDoc}
  • p – {@inheritDoc}
Throws:
Implementation Requirements:The default implementation of this method in AbstractElementVisitor6 will always throw new UnknownElementException(e, p). This behavior is not required of a subclass.
Returns: {@inheritDoc}
/** * {@inheritDoc} * * @implSpec The default implementation of this method in * {@code AbstractElementVisitor6} will always throw * {@code new UnknownElementException(e, p)}. * This behavior is not required of a subclass. * * @param e {@inheritDoc} * @param p {@inheritDoc} * @return {@inheritDoc} * @throws UnknownElementException * a visitor implementation may optionally throw this exception */
@Override public R visitUnknown(Element e, P p) { throw new UnknownElementException(e, p); }
{@inheritDoc}
Params:
  • e – {@inheritDoc}
  • p – {@inheritDoc}
Implementation Requirements:Visits a ModuleElement by calling visitUnknown.
Returns: {@inheritDoc}
Since:9
@specJPMS
/** * {@inheritDoc} * * @implSpec Visits a {@code ModuleElement} by calling {@code * visitUnknown}. * * @param e {@inheritDoc} * @param p {@inheritDoc} * @return {@inheritDoc} * * @since 9 * @spec JPMS */
@Override public R visitModule(ModuleElement e, P p) { // Use implementation from interface default method return ElementVisitor.super.visitModule(e, p); } }