Mercurial > jdk8-mips64-public > langtools / file revision

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  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the LICENSE file that accompanied this code.

  *

  * This code 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

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 package javax.lang.model.util;

 import javax.lang.model.element.*;

 import static javax.lang.model.element.ElementKind.*;

 import javax.annotation.processing.SupportedSourceVersion;

 import static javax.lang.model.SourceVersion.*;

 import javax.lang.model.SourceVersion;

 /**

  * A visitor of program elements based on their {@linkplain

  * ElementKind kind} with default behavior appropriate for the {@link

  * SourceVersion#RELEASE_6 RELEASE_6} source version.  For {@linkplain

  * Element elements} <tt><i>XYZ</i></tt> that may have more than one

  * kind, the <tt>visit<i>XYZ</i></tt> methods in this class delegate

  * to the <tt>visit<i>XYZKind</i></tt> method corresponding to the

  * first argument's kind.  The <tt>visit<i>XYZKind</i></tt> methods

  * 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 or the

  * {@code ElementKind} {@code enum} used in this case may have

  * constants 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 {@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 kind

  * 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.

  *

  * <p>Note that adding a default implementation of a new visit method

  * in a visitor class will occur instead of adding a <em>default

  * method</em> directly in the visitor interface since a Java SE 8

  * language feature cannot be used to this version of the API since

  * this version is required to be runnable on Java SE 7

  * implementations.  Future versions of the API that are only required

  * to run on Java SE 8 and later may take advantage of default methods

  * in this situation.

  *

  * @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 Ahé

  *

  * @see ElementKindVisitor7

  * @see ElementKindVisitor8

  * @since 1.6

  */

 @SupportedSourceVersion(RELEASE_6)

 public class ElementKindVisitor6<R, P>

                   extends SimpleElementVisitor6<R, P> {

     /**

      * Constructor for concrete subclasses; uses {@code null} for the

      * default value.

      */

     protected ElementKindVisitor6() {

         super(null);

     }

     /**

      * Constructor for concrete subclasses; uses the argument for the

      * default value.

      *

      * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}

      */

     protected ElementKindVisitor6(R defaultValue) {

         super(defaultValue);

     }

     /**

      * {@inheritDoc}

      *

      * The element argument has kind {@code PACKAGE}.

      *

      * @param e {@inheritDoc}

      * @param p {@inheritDoc}

      * @return  {@inheritDoc}

      */

     @Override

     public R visitPackage(PackageElement e, P p) {

         assert e.getKind() == PACKAGE: "Bad kind on PackageElement";

         return defaultAction(e, p);

     }

     /**

      * Visits a type element, dispatching to the visit method for the

      * specific {@linkplain ElementKind kind} of type, {@code

      * ANNOTATION_TYPE}, {@code CLASS}, {@code ENUM}, or {@code

      * INTERFACE}.

      *

      * @param e {@inheritDoc}

      * @param p {@inheritDoc}

      * @return  the result of the kind-specific visit method

      */

     @Override

     public R visitType(TypeElement e, P p) {

         ElementKind k = e.getKind();

         switch(k) {

         case ANNOTATION_TYPE:

             return visitTypeAsAnnotationType(e, p);

         case CLASS:

             return visitTypeAsClass(e, p);

         case ENUM:

             return visitTypeAsEnum(e, p);

         case INTERFACE:

             return visitTypeAsInterface(e, p);

         default:

             throw new AssertionError("Bad kind " + k + " for TypeElement" + e);

         }

     }

     /**

      * Visits an {@code ANNOTATION_TYPE} type element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitTypeAsAnnotationType(TypeElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code CLASS} type element by calling {@code

      * defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitTypeAsClass(TypeElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits an {@code ENUM} type element by calling {@code

      * defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitTypeAsEnum(TypeElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits an {@code INTERFACE} type element by calling {@code

      * defaultAction}.

      *.

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitTypeAsInterface(TypeElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a variable element, dispatching to the visit method for

      * the specific {@linkplain ElementKind kind} of variable, {@code

      * ENUM_CONSTANT}, {@code EXCEPTION_PARAMETER}, {@code FIELD},

      * {@code LOCAL_VARIABLE}, {@code PARAMETER}, or {@code RESOURCE_VARIABLE}.

      *

      * @param e {@inheritDoc}

      * @param p {@inheritDoc}

      * @return  the result of the kind-specific visit method

      */

     @Override

     public R visitVariable(VariableElement e, P p) {

         ElementKind k = e.getKind();

         switch(k) {

         case ENUM_CONSTANT:

             return visitVariableAsEnumConstant(e, p);

         case EXCEPTION_PARAMETER:

             return visitVariableAsExceptionParameter(e, p);

         case FIELD:

             return visitVariableAsField(e, p);

         case LOCAL_VARIABLE:

             return visitVariableAsLocalVariable(e, p);

         case PARAMETER:

             return visitVariableAsParameter(e, p);

         case RESOURCE_VARIABLE:

             return visitVariableAsResourceVariable(e, p);

         default:

             throw new AssertionError("Bad kind " + k + " for VariableElement" + e);

         }

     }

     /**

      * Visits an {@code ENUM_CONSTANT} variable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitVariableAsEnumConstant(VariableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits an {@code EXCEPTION_PARAMETER} variable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitVariableAsExceptionParameter(VariableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code FIELD} variable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitVariableAsField(VariableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code LOCAL_VARIABLE} variable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitVariableAsLocalVariable(VariableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code PARAMETER} variable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitVariableAsParameter(VariableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code RESOURCE_VARIABLE} variable element by calling

      * {@code visitUnknown}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code visitUnknown}

      *

      * @since 1.7

      */

     public R visitVariableAsResourceVariable(VariableElement e, P p) {

         return visitUnknown(e, p);

     }

     /**

      * Visits an executable element, dispatching to the visit method

      * for the specific {@linkplain ElementKind kind} of executable,

      * {@code CONSTRUCTOR}, {@code INSTANCE_INIT}, {@code METHOD}, or

      * {@code STATIC_INIT}.

      *

      * @param e {@inheritDoc}

      * @param p {@inheritDoc}

      * @return  the result of the kind-specific visit method

      */

     @Override

     public R visitExecutable(ExecutableElement e, P p) {

         ElementKind k = e.getKind();

         switch(k) {

         case CONSTRUCTOR:

             return visitExecutableAsConstructor(e, p);

         case INSTANCE_INIT:

             return visitExecutableAsInstanceInit(e, p);

         case METHOD:

             return visitExecutableAsMethod(e, p);

         case STATIC_INIT:

             return visitExecutableAsStaticInit(e, p);

         default:

             throw new AssertionError("Bad kind " + k + " for ExecutableElement" + e);

         }

     }

     /**

      * Visits a {@code CONSTRUCTOR} executable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitExecutableAsConstructor(ExecutableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits an {@code INSTANCE_INIT} executable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitExecutableAsInstanceInit(ExecutableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code METHOD} executable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitExecutableAsMethod(ExecutableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * Visits a {@code STATIC_INIT} executable element by calling

      * {@code defaultAction}.

      *

      * @param e the element to visit

      * @param p a visitor-specified parameter

      * @return  the result of {@code defaultAction}

      */

     public R visitExecutableAsStaticInit(ExecutableElement e, P p) {

         return defaultAction(e, p);

     }

     /**

      * {@inheritDoc}

      *

      * The element argument has kind {@code TYPE_PARAMETER}.

      *

      * @param e {@inheritDoc}

      * @param p {@inheritDoc}

      * @return  {@inheritDoc}

      */

     @Override

     public R visitTypeParameter(TypeParameterElement e, P p) {

         assert e.getKind() == TYPE_PARAMETER: "Bad kind on TypeParameterElement";

         return defaultAction(e, p);

     }

 }