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

 /*

  * Copyright 2009 Sun Microsystems, Inc.  All Rights Reserved.

  * 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.  Sun designates this

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

  * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  */

 package com.sun.source.util;

 import java.util.ArrayList;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Set;

 import javax.annotation.processing.*;

 import javax.lang.model.element.Name;

 import javax.lang.model.element.TypeElement;

 import javax.lang.model.util.ElementFilter;

 import com.sun.tools.javac.processing.JavacProcessingEnvironment;

 import com.sun.tools.javac.util.Context;

 import com.sun.tools.javac.util.Log;

 import com.sun.source.tree.ClassTree;

 /**

  * This class is an abstract annotation processor designed to be a

  * convenient superclass for concrete "type processors", processors that

  * require the type information in the processed source.

  *

  * <p>Type processing occurs in one round after the tool (e.g. java compiler)

  * analyzes the source (all sources taken as input to the tool and sources

  * generated by other annotation processors).

  *

  * <p>The tool infrastructure will interact with classes extending this abstract

  * class as follows:

  *

  * <ol>

  * [1-3: Identical to {@link Processor} life cycle]

  *

  * <li>If an existing {@code Processor} object is not being used, to

  * create an instance of a processor the tool calls the no-arg

  * constructor of the processor class.

  *

  * <li>Next, the tool calls the {@link #init init} method with

  * an appropriate {@code ProcessingEnvironment}.

  *

  * <li>Afterwards, the tool calls {@link #getSupportedAnnotationTypes

  * getSupportedAnnotationTypes}, {@link #getSupportedOptions

  * getSupportedOptions}, and {@link #getSupportedSourceVersion

  * getSupportedSourceVersion}.  These methods are only called once per

  * run, not on each round.

  *

  * [4-5Unique to {@code AbstractTypeProcessor} subclasses]

  *

  * <li>For each class containing a supported annotation, the tool calls

  * {@link #typeProcess(TypeElement, TreePath) typeProcess} method on the

  * {@code Processor}.  The class is guaranteed to be type-checked Java code

  * and all the tree type and symbol information is resolved.

  *

  * <li>Finally, the tools calls the

  * {@link #typeProcessingOver() typeProcessingOver} method

  * on the {@code Processor}.

  *

  * </ol>

  *

  * <p>The tool is permitted to ask type processors to process a class once

  * it is analyzed before the rest of classes are analyzed.  The tool is also

  * permitted to stop type processing immediately if any errors are raised,

  * without invoking {@code typeProcessingOver}

  *

  * <p>A subclass may override any of the methods in this class, as long as the

  * general {@link javax.annotation.processing.Processor Processor}

  * contract is obeyed, with one notable exception.

  * {@link #process(Set, RoundEnvironment)} may not be overridden, as it

  * is called during the regular annotation phase before classes are analyzed.

  *

  * @author Mahmood Ali

  * @since 1.7

  */

 public abstract class AbstractTypeProcessor extends AbstractProcessor {

     private final Set<Name> elements = new HashSet<Name>();

     private boolean hasInvokedTypeProcessingOver = false;

     private JavacProcessingEnvironment env;

     private final AttributionTaskListener listener = new AttributionTaskListener();

     /**

      * Constructor for subclasses to call.

      */

     protected AbstractTypeProcessor() { }

     /**

      * {@inheritDoc}

      */

     @Override

     public void init(ProcessingEnvironment env) {

         super.init(env);

         this.env = (JavacProcessingEnvironment)env;

         prepareContext(this.env.getContext());

     }

     /**

      * The use of this method is obsolete in type processors.  The method is

      * called during regular annotation processing phase only.

      */

     @Override

     public final boolean process(Set<? extends TypeElement> annotations,

             RoundEnvironment roundEnv) {

         for (TypeElement elem : ElementFilter.typesIn(roundEnv.getRootElements())) {

             elements.add(elem.getQualifiedName());

         }

         return false;

     }

     /**

      * Processes a fully analyzed class that contains a supported annotation

      * (look {@link #getSupportedAnnotationTypes()}).

      *

      * <p>The passed class is always a valid type-checked Java code.

      *

      * @param element       element of the analyzed class

      * @param tree  the tree path to the element, with the leaf being a

      *              {@link ClassTree}

      */

     public abstract void typeProcess(TypeElement element, TreePath tree);

     /**

      * A method to be called once all the classes are processed and no error

      * is reported.

      *

      * <p>Subclasses may override this method to do any aggregate analysis

      * (e.g. generate report, persistence) or resource deallocation.

      *

      * <p>If an error (a Java error or a processor error) is reported, this

      * method is not guaranteed to be invoked.

      */

     public void typeProcessingOver() { }

     /**

      * adds a listener for attribution.

      */

     private void prepareContext(Context context) {

         TaskListener otherListener = context.get(TaskListener.class);

         if (otherListener == null) {

             context.put(TaskListener.class, listener);

         } else {

             // handle cases of multiple listeners

             context.put(TaskListener.class, (TaskListener)null);

             TaskListeners listeners = new TaskListeners();

             listeners.add(otherListener);

             listeners.add(listener);

             context.put(TaskListener.class, listeners);

         }

     }

     /**

      * A task listener that invokes the processor whenever a class is fully

      * analyzed.

      */

     private final class AttributionTaskListener implements TaskListener {

         @Override

         public void finished(TaskEvent e) {

             Log log = Log.instance(env.getContext());

             if (!hasInvokedTypeProcessingOver && elements.isEmpty() && log.nerrors == 0) {

                 typeProcessingOver();

                 hasInvokedTypeProcessingOver = true;

             }

             if (e.getKind() != TaskEvent.Kind.ANALYZE)

                 return;

             if (e.getTypeElement() == null)

                 throw new AssertionError("event task without a type element");

             if (e.getCompilationUnit() == null)

                 throw new AssertionError("even task without compilation unit");

             if (!elements.remove(e.getTypeElement().getQualifiedName()))

                 return;

             if (log.nerrors != 0)

                 return;

             TypeElement elem = e.getTypeElement();

             TreePath p = Trees.instance(env).getPath(elem);

             typeProcess(elem, p);

             if (!hasInvokedTypeProcessingOver && elements.isEmpty() && log.nerrors == 0) {

                 typeProcessingOver();

                 hasInvokedTypeProcessingOver = true;

             }

         }

         @Override

         public void started(TaskEvent e) { }

     }

     /**

      * A task listener multiplexer.

      */

     private static class TaskListeners implements TaskListener {

         private final List<TaskListener> listeners = new ArrayList<TaskListener>();

         public void add(TaskListener listener) {

             listeners.add(listener);

         }

         public void remove(TaskListener listener) {

             listeners.remove(listener);

         }

         @Override

         public void finished(TaskEvent e) {

             for (TaskListener listener : listeners)

                 listener.finished(e);

         }

         @Override

         public void started(TaskEvent e) {

             for (TaskListener listener : listeners)

                 listener.started(e);

         }

     }

 }