1   /*
    2    * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   package com.sun.tools.javac.parser;
   27   
   28   import java.nio.CharBuffer;
   29   
   30   import com.sun.tools.javac.code.Source;
   31   import com.sun.tools.javac.util.Context;
   32   import com.sun.tools.javac.util.Log;
   33   import com.sun.tools.javac.util.Names;
   34   
   35   
   36   /**
   37    * A factory for creating scanners.
   38    *
   39    *  <p><b>This is NOT part of any supported API.
   40    *  If you write code that depends on this, you do so at your own
   41    *  risk.  This code and its internal interfaces are subject to change
   42    *  or deletion without notice.</b>
   43    */
   44   public class ScannerFactory {
   45       /** The context key for the scanner factory. */
   46       public static final Context.Key<ScannerFactory> scannerFactoryKey =
   47           new Context.Key<ScannerFactory>();
   48   
   49       /** Get the Factory instance for this context. */
   50       public static ScannerFactory instance(Context context) {
   51           ScannerFactory instance = context.get(scannerFactoryKey);
   52           if (instance == null)
   53               instance = new ScannerFactory(context);
   54           return instance;
   55       }
   56   
   57       final Log log;
   58       final Names names;
   59       final Source source;
   60       final Keywords keywords;
   61   
   62       /** Create a new scanner factory. */
   63       protected ScannerFactory(Context context) {
   64           context.put(scannerFactoryKey, this);
   65           this.log = Log.instance(context);
   66           this.names = Names.instance(context);
   67           this.source = Source.instance(context);
   68           this.keywords = Keywords.instance(context);
   69       }
   70   
   71       public Scanner newScanner(CharSequence input, boolean keepDocComments) {
   72           if (input instanceof CharBuffer) {
   73               CharBuffer buf = (CharBuffer) input;
   74               if (keepDocComments)
   75                   return new DocCommentScanner(this, buf);
   76               else
   77                   return new Scanner(this, buf);
   78           } else {
   79               char[] array = input.toString().toCharArray();
   80               return newScanner(array, array.length, keepDocComments);
   81           }
   82       }
   83   
   84       public Scanner newScanner(char[] input, int inputLength, boolean keepDocComments) {
   85           if (keepDocComments)
   86               return new DocCommentScanner(this, input, inputLength);
   87           else
   88               return new Scanner(this, input, inputLength);
   89       }
   90   }