1 /*

     2  * Copyright (c) 2007, 2018, 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 package nsk.share.classload;

    25 

    26 import java.io.File;

    27 import java.io.IOException;

    28 import java.io.InputStream;

    29 import java.io.FileInputStream;

    30 

    31 import java.util.Arrays;

    32 import java.nio.file.Path;

    33 import java.nio.file.Paths;

    34 import java.nio.file.Files;

    35 

    36 public class ClassLoadUtils {

    37     private ClassLoadUtils() {

    38     }

    39 

    40     /**

    41      * Get filename of class file from classpath for given class name.

    42      *

    43      * @param className class name

    44      * @return filename or null if not found

    45      */

    46     public static String getClassPath(String className) {

    47         String fileName = className.replace(".", File.separator) + ".class";

    48         String[] classPath = System.getProperty("java.class.path").split(File.pathSeparator);

    49         File target = null;

    50         int i;

    51         for (i = 0; i < classPath.length; ++i) {

    52             target = new File(classPath[i] + File.separator + fileName);

    53             System.out.println("Try: " + target);

    54             if (target.exists()) {

    55                 break;

    56             }

    57         }

    58         if (i != classPath.length) {

    59             return classPath[i];

    60         }

    61         return null;

    62     }

    63 

    64     /**

    65      * Get filename of class file from classpath for given class name.

    66      *

    67      * @param className class name

    68      * @return filename or null if not found

    69      */

    70     public static String getClassPathFileName(String className) {

    71         String fileName = className.replace(".", File.separator) + ".class";

    72         String[] classPath = System.getProperty("java.class.path").split(File.pathSeparator);

    73         File target = null;

    74         int i;

    75         for (i = 0; i < classPath.length; ++i) {

    76             target = new File(classPath[i] + File.separator + fileName);

    77             System.out.println("Try: " + target);

    78             if (target.exists()) {

    79                 break;

    80             }

    81         }

    82         if (i != classPath.length) {

    83             try {

    84                 return target.getCanonicalPath();

    85             } catch (IOException e) {

    86                 return null;

    87             }

    88         }

    89         return null;

    90     }

    91 

    92     public static String getRedefineClassFileName(String dir, String className) {

    93         String fileName = className.replace(".", File.separator) + ".class";

    94         return Arrays.stream(System.getProperty("java.class.path").split(File.pathSeparator))

    95                      .map(Paths::get)

    96                      .map(p -> p.resolve(dir))

    97                      .map(p -> p.resolve(fileName))

    98                      .filter(p -> Files.exists(p))

    99                      .map(Path::toAbsolutePath)

   100                      .map(Path::toString)

   101                      .findAny()

   102                      .orElse(null);

   103     }

   104 

   105     /**

   106      * Get filename of class file which is to be redefined.

   107      */

   108     public static String getRedefineClassFileName(String className) {

   109             return getRedefineClassFileName("newclass", className);

   110     }

   111 }