1 /*

     2  * Copyright (c) 2002, 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.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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

    13  * accompanied this code).

    14  *

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

    16  * 2 along with this work; if not, write to the Free Software Foundation,

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

    18  *

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

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

    21  * questions.

    22  *

    23  */

    24 

    25 package sun.jvm.hotspot.bugspot;

    26 

    27 import java.io.*;

    28 

    29 /** Scans a .java file for the package that it is in. */

    30 

    31 public class PackageScanner {

    32 

    33   public PackageScanner() {

    34   }

    35 

    36   public String scan(String filename) {

    37     return scan(new File(filename));

    38   }

    39 

    40   /** Returns the String comprising the package name of the classes in

    41       this .java file. Returns the (non-null) empty string if any

    42       error occurs or if the classes are in the unnamed package. */

    43   public String scan(File file) {

    44     BufferedReader buf = null;

    45     String res = "";

    46     try {

    47       buf = new BufferedReader(new FileReader(file));

    48       StreamTokenizer tok = new StreamTokenizer(buf);

    49       tok.slashStarComments(true);

    50       tok.slashSlashComments(true);

    51       if (tok.nextToken() != StreamTokenizer.TT_WORD) {

    52         return res;

    53       }

    54       if (!tok.sval.equals("package")) {

    55         return res;

    56       }

    57       if (tok.nextToken() != StreamTokenizer.TT_WORD) {

    58         return res;

    59       }

    60       res = tok.sval;

    61       return res;

    62     } catch (FileNotFoundException e) {

    63       return res;

    64     } catch (IOException e) {

    65       return res;

    66     } finally {

    67       try {

    68         if (buf != null) {

    69           buf.close();

    70         }

    71       } catch (IOException e) {

    72       }

    73     }

    74   }

    75 

    76   public static void main(String[] args) {

    77     if (args.length != 1) {

    78       usage();

    79     }

    80 

    81     System.out.println(new PackageScanner().scan(args[0]));

    82   }

    83 

    84   private static void usage() {

    85     System.err.println("Usage: java PackageScanner <.java file name>");

    86     System.err.println("Prints package the .java file is in to stdout.");

    87     System.exit(1);

    88   }

    89 }