1 /*
   2  * Copyright (c) 2012, 2020, 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 jdk.internal.loader;
  27 
  28 import java.io.File;
  29 import java.util.ArrayList;
  30 
  31 class ClassLoaderHelper {
  32 
  33     private ClassLoaderHelper() {}
  34 
  35     /**
  36      * Returns an alternate path name for the given file
  37      * such that if the original pathname did not exist, then the
  38      * file may be located at the alternate location.
  39      * For most platforms, this behavior is not supported and returns null.
  40      */
  41     static File mapAlternativeName(File lib) {
  42         return null;
  43     }
  44 
  45     /**
  46      * Parse a PATH env variable.
  47      *
  48      * Empty elements will be replaced by dot.
  49      */
  50     static String[] parsePath(String ldPath) {
  51         char ps = File.pathSeparatorChar;
  52         ArrayList<String> paths = new ArrayList<>();
  53         int pathStart = 0;
  54         int pathEnd;
  55         while ((pathEnd = ldPath.indexOf(ps, pathStart)) >= 0) {
  56             paths.add((pathStart < pathEnd) ?
  57                     ldPath.substring(pathStart, pathEnd) : ".");
  58             pathStart = pathEnd + 1;
  59         }
  60         int ldLen = ldPath.length();
  61         paths.add((pathStart < ldLen) ?
  62                 ldPath.substring(pathStart, ldLen) : ".");
  63         return paths.toArray(new String[paths.size()]);
  64     }
  65 }