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

 /*

  * Copyright (c) 2011, 2013, Oracle and/or its affiliates. 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.  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

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 package com.sun.tools.javac.code;

 import java.util.HashMap;

 import java.util.Map;

 import com.sun.tools.javac.tree.EndPosTable;

 import com.sun.tools.javac.tree.JCTree;

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

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

 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;

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

 /**

  *

  * <p><b>This is NOT part of any supported API.

  * If you write code that depends on this, you do so at your own risk.

  * This code and its internal interfaces are subject to change or

  * deletion without notice.</b>

  */

 public class DeferredLintHandler {

     protected static final Context.Key<DeferredLintHandler> deferredLintHandlerKey =

         new Context.Key<DeferredLintHandler>();

     public static DeferredLintHandler instance(Context context) {

         DeferredLintHandler instance = context.get(deferredLintHandlerKey);

         if (instance == null)

             instance = new DeferredLintHandler(context);

         return instance;

     }

     protected DeferredLintHandler(Context context) {

         context.put(deferredLintHandlerKey, this);

         this.currentPos = IMMEDIATE_POSITION;

     }

     /**An interface for deferred lint reporting - loggers passed to

      * {@link #report(LintLogger) } will be called when

      * {@link #flush(DiagnosticPosition) } is invoked.

      */

     public interface LintLogger {

         void report();

     }

     private DiagnosticPosition currentPos;

     private Map<DiagnosticPosition, ListBuffer<LintLogger>> loggersQueue = new HashMap<DiagnosticPosition, ListBuffer<LintLogger>>();

     /**Associate the given logger with the current position as set by {@link #setPos(DiagnosticPosition) }.

      * Will be invoked when {@link #flush(DiagnosticPosition) } will be invoked with the same position.

      * <br>

      * Will invoke the logger synchronously if {@link #immediate() } was called

      * instead of {@link #setPos(DiagnosticPosition) }.

      */

     public void report(LintLogger logger) {

         if (currentPos == IMMEDIATE_POSITION) {

             logger.report();

         } else {

             ListBuffer<LintLogger> loggers = loggersQueue.get(currentPos);

             if (loggers == null) {

                 loggersQueue.put(currentPos, loggers = ListBuffer.<LintLogger>lb());

             }

             loggers.append(logger);

         }

     }

     /**Invoke all {@link LintLogger}s that were associated with the provided {@code pos}.

      */

     public void flush(DiagnosticPosition pos) {

         ListBuffer<LintLogger> loggers = loggersQueue.get(pos);

         if (loggers != null) {

             for (LintLogger lintLogger : loggers) {

                 lintLogger.report();

             }

             loggersQueue.remove(pos);

         }

     }

     /**Sets the current position to the provided {@code currentPos}. {@link LintLogger}s

      * passed to subsequent invocations of {@link #report(LintLogger) } will be associated

      * with the given position.

      */

     public DiagnosticPosition setPos(DiagnosticPosition currentPos) {

         DiagnosticPosition prevPosition = this.currentPos;

         this.currentPos = currentPos;

         return prevPosition;

     }

     /**{@link LintLogger}s passed to subsequent invocations of

      * {@link #report(LintLogger) } will be invoked immediately.

      */

     public DiagnosticPosition immediate() {

         return setPos(IMMEDIATE_POSITION);

     }

     private static final DiagnosticPosition IMMEDIATE_POSITION = new DiagnosticPosition() {

         @Override

         public JCTree getTree() {

             Assert.error();

             return null;

         }

         @Override

         public int getStartPosition() {

             Assert.error();

             return -1;

         }

         @Override

         public int getPreferredPosition() {

             Assert.error();

             return -1;

         }

         @Override

         public int getEndPosition(EndPosTable endPosTable) {

             Assert.error();

             return -1;

         }

     };

 }