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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
    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:a visitor-specified result
/**
     * {@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 a visitor-specified result
     * @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:the result of visitUnknown
Since:9
@specJPMS
/**
     * {@inheritDoc}
     *
     * @implSpec Visits a {@code ModuleElement} by calling {@code
     * visitUnknown}.
     *
     * @param e  {@inheritDoc}
     * @param p  {@inheritDoc}
     * @return the result of {@code visitUnknown}
     *
     * @since 9
     * @spec JPMS
     */
    @Override
    public R visitModule(ModuleElement e, P p) {
        // Use implementation from interface default method
        return ElementVisitor.super.visitModule(e, p);
    }
}