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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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package javax.lang.model.util;

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


A simple visitor of program elements with default behavior appropriate for the RELEASE_8 source version. Visit methods corresponding to RELEASE_8 and earlier language constructs call defaultAction, passing their arguments to defaultAction's corresponding parameters. 
 Methods in this class may be overridden subject to their general contract. Note that annotating methods in concrete subclasses with @Override will help ensure that methods are overridden as intended. 
 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 simple 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. 
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:1.8
/**
 * A simple visitor of program elements with default behavior
 * appropriate for the {@link SourceVersion#RELEASE_8 RELEASE_8}
 * source version.
 *
 * Visit methods corresponding to {@code RELEASE_8} and earlier
 * language constructs call {@link #defaultAction defaultAction},
 * passing their arguments to {@code defaultAction}'s corresponding
 * parameters.
 *
 * <p> Methods in this class may be overridden subject to their
 * general contract.  Note that annotating methods in concrete
 * subclasses with {@link java.lang.Override @Override} will help
 * ensure that methods are overridden as intended.
 *
 * <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 simple 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 {@code 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.
 *
 * @see SimpleElementVisitor6
 * @see SimpleElementVisitor7
 * @see SimpleElementVisitor9
 * @since 1.8
 */
@SupportedSourceVersion(RELEASE_8)
public class SimpleElementVisitor8<R, P> extends SimpleElementVisitor7<R, P> {
    
Constructor for concrete subclasses; uses null for the default value. 
/**
     * Constructor for concrete subclasses; uses {@code null} for the
     * default value.
     */
    @SuppressWarnings("deprecation") // Superclass constructor deprecated
    protected SimpleElementVisitor8(){
        super(null);
    }

    
Constructor for concrete subclasses; uses the argument for the
default value.

Params:
/**
     * Constructor for concrete subclasses; uses the argument for the
     * default value.
     *
     * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
     */
    @SuppressWarnings("deprecation") // Superclass constructor deprecated
    protected SimpleElementVisitor8(R defaultValue){
        super(defaultValue);
    }
}