path: root/javax/lang/model/util/SimpleAnnotationValueVisitor6.java

/* SimpleAnnotationValueVisitor6.java -- A simple visitor implementation for 1.6.
   Copyright (C) 2015  Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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terms of your choice, provided that you also meet, for each linked
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package javax.lang.model.util;

import java.util.List;

import javax.annotation.processing.SupportedSourceVersion;

import javax.lang.model.SourceVersion;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.AnnotationValue;
import javax.lang.model.element.VariableElement;
import javax.lang.model.type.TypeMirror;

/**
 * <p>A simple implementation of {@link AnnotationValueVisitor} for the
 * 1.6 version of the Java programming language
 * ({@link SourceVersion#RELEASE_6}).  Each {@code visitXYZ} method
 * redirects to {@code defaultAction(value, parameter)}.
 * Implementors may extend this class and provide alternative
 * implementations of {@link #defaultAction(Object, P)} and
 * the {@code visitXYZ} methods as appropriate.</p>
 * <p>As the interface this class implements may be extended in future,
 * in order to support later language versions, methods beginning with
 * the phrase {@code "visit"} should be avoided in subclasses.  This
 * class itself will be extended to direct these new methods to the
 * {@link #visitUnknown(AnnotationValue,P)} method and a new class will be
 * added to provide implementations for the new language version.
 * At this time, all or some of this class may be deprecated.</p>
 * 
 * @param <R> the return type of the visitor's methods.  {@code Void}
 *            can be used where there is no return value.
 * @param <P> the type of the additional parameter supplied to the visitor's
 *            methods.
 *
 * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
 * @since 1.6
 */
@SupportedSourceVersion(SourceVersion.RELEASE_6)
public class SimpleAnnotationValueVisitor6<R,P> extends AbstractAnnotationValueVisitor6<R,P>
{

  /**
   * The default value returned by calls to {@link #defaultAction(Object, P)}.
   */
  protected final R DEFAULT_VALUE;

  /**
   * Constructs a new {@link SimpleAnnotationValueVisitor6} with a {@code null}
   * default value.
   */
  protected SimpleAnnotationValueVisitor6()
  {
    this(null);
  }

  /**
   * Constructs a new {@link SimpleAnnotationValueVisitor6} with the specified
   * default value.
   *
   * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}.
   */
  protected SimpleAnnotationValueVisitor6(R defaultValue)
  {
    DEFAULT_VALUE = defaultValue;
  }

  /**
   * The default action for all visitor methods.  The default implementation
   * simply returns {@link #DEFAULT_VALUE}.
   *
   * @param obj the object to act upon.
   * @param parameter the optional parameter supplied to the visitor.
   * @return {@link #DEFAULT_VALUE}.
   */
  protected R defaultAction(Object obj, P parameter)
  {
    return DEFAULT_VALUE;
  }

  /**
   * Visits a boolean value in an annotation.  This implementation simply
   * calls {@code defaultAction(bool, parameter)}.
   *
   * @param bool the boolean value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(bool, parameter)}.
   */
  @Override
  public R visitBoolean(boolean bool, P parameter)
  {
    return defaultAction(bool, parameter);
  }

  /**
   * Visits a byte value in an annotation.  This implementation simply
   * calls {@code defaultAction(val, parameter)}.
   *
   * @param val the byte value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(val, parameter)}.
   */
  @Override
  public R visitByte(byte val, P parameter)
  {
    return defaultAction(val, parameter);
  }

  /**
   * Visits a character value in an annotation.  This implementation simply
   * calls {@code defaultAction(character, parameter)}.
   *
   * @param character the character value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(character, parameter)}.
   */
  @Override
  public R visitChar(char character, P parameter)
  {
    return defaultAction(character, parameter);
  }

  /**
   * Visits a double value in an annotation.  This implementation simply
   * calls {@code defaultAction(val, parameter)}.
   *
   * @param val the double value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(val, parameter)}.
   */
  @Override
  public R visitDouble(double val, P parameter)
  {
    return defaultAction(val, parameter);
  }

  /**
   * Visits a float value in an annotation.  This implementation simply
   * calls {@code defaultAction(val, parameter)}.
   *
   * @param val the float value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(val, parameter)}.
   */
  @Override
  public R visitFloat(float val, P parameter)
  {
    return defaultAction(val, parameter);
  }

  /**
   * Visits an integer value in an annotation.  This implementation simply
   * calls {@code defaultAction(val, parameter)}.
   *
   * @param val the integer value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(val, parameter)}.
   */
  @Override
  public R visitInt(int val, P parameter)
  {
    return defaultAction(val, parameter);
  }

  /**
   * Visits a long value in an annotation.  This implementation simply
   * calls {@code defaultAction(val, parameter)}.
   *
   * @param val the long value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(val, parameter)}.
   */
  @Override
  public R visitLong(long val, P parameter)
  {
    return defaultAction(val, parameter);
  }

  /**
   * Visits a short value in an annotation.  This implementation simply
   * calls {@code defaultAction(val, parameter)}.
   *
   * @param val the short value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(val, parameter)}.
   */
  @Override
  public R visitShort(short val, P parameter)
  {
    return defaultAction(val, parameter);
  }

  /**
   * Visits a String value in an annotation.  This implementation simply
   * calls {@code defaultAction(str, parameter)}.
   *
   * @param str the String value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(str, parameter)}.
   */
  @Override
  public R visitString(String str, P parameter)
  {
    return defaultAction(str, parameter);
  }

  /**
   * Visits a type value in an annotation.  This implementation simply
   * calls {@code defaultAction(type, parameter)}.
   *
   * @param type the type value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(type, parameter)}.
   */
  @Override
  public R visitType(TypeMirror type, P parameter)
  {
    return defaultAction(type, parameter);
  }

  /**
   * Visits an enumeration constant in an annotation.  This implementation simply
   * calls {@code defaultAction(enumConst, parameter)}.
   *
   * @param enumConst the enumeration constant to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(enumConst, parameter)}.
   */
  @Override
  public R visitEnumConstant(VariableElement enumConst, P parameter)
  {
    return defaultAction(enumConst, parameter);
  }

  /**
   * Visits an annotation value in an annotation.  This implementation simply
   * calls {@code defaultAction(annotation, parameter)}.
   *
   * @param annotation the annotation value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(annotation, parameter)}.
   */
  @Override
  public R visitAnnotation(AnnotationMirror annotation, P parameter)
  {
    return defaultAction(annotation, parameter);
  }

  /**
   * Visits an array value in an annotation.  This implementation simply
   * calls {@code defaultAction(array, parameter)}.
   *
   * @param array the array value to visit.
   * @param parameter the additional parameter, specific to the visitor.
   *        May be {@code null}.
   * @return the result of {@code defaultAction(array, parameter)}.
   */
  @Override
  public R visitArray(List<? extends AnnotationValue> array, P parameter)
  {
    return defaultAction(array, parameter);
  }

}