1 /*
   2  * Copyright (c) 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 test;
  25 
  26 import java.util.*;
  27 import java.io.*;
  28 
  29 public class IAE_Loader1 extends ClassLoader {
  30 
  31     private final Set<String> names = new HashSet<>();
  32 
  33     public IAE_Loader1(String name, String[] names) {
  34         super(name, ClassLoader.getSystemClassLoader());
  35         for (String n : names) this.names.add(n);
  36     }
  37 
  38     protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException {
  39         if (!names.contains(name)) {
  40             return super.loadClass(name, resolve);
  41         }
  42         String filename = name.replace('.', '/') + ".class";
  43         Class<?> result = null;
  44         try (InputStream data = getResourceAsStream(filename)) {
  45             if (data == null) {
  46                 throw new ClassNotFoundException();
  47             }
  48             try (ByteArrayOutputStream buffer = new ByteArrayOutputStream()) {
  49                 int b;
  50                 do {
  51                     b = data.read();
  52                     if (b >= 0) buffer.write(b);
  53                 } while (b >= 0);
  54                 byte[] bytes = buffer.toByteArray();
  55                 result = defineClass(name, bytes, 0, bytes.length);
  56             }
  57         } catch (IOException e) {
  58             throw new ClassNotFoundException("Error reading class file", e);
  59         }
  60         if (resolve) resolveClass(result);
  61         return result;
  62     }
  63 
  64 }