1 /*
   2  * Copyright (c) 2015, 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 package utils;
  24 
  25 import jdk.test.lib.classloader.GeneratingClassLoader;
  26 
  27 /**
  28  * Garbage producer that creates classes loaded with GeneratingClassLoader.
  29  *
  30  * Note: this class is not thread-safe.
  31  */
  32 class GeneratedClassProducer {
  33 
  34     private int number;
  35     private String className;
  36     private StringBuilder sb = new StringBuilder();
  37     private int minPerClassLoader = 50;
  38     private int maxPerClassLoader = 150;
  39     private int count;
  40     private GeneratingClassLoader loader = new GeneratingClassLoader();
  41 
  42     GeneratedClassProducer() {
  43         this(GeneratingClassLoader.DEFAULT_CLASSNAME);
  44     }
  45 
  46     GeneratedClassProducer(String className) {
  47         this.className = className;
  48     }
  49 
  50     String getNewName() {
  51         sb.delete(0, sb.length());
  52         sb.append("Class");
  53         sb.append(number);
  54         int n = loader.getNameLength() - sb.length();
  55         for (int i = 0; i < n; ++i) {
  56             sb.append('_');
  57         }
  58         return sb.toString();
  59     }
  60 
  61     Class create(long memory) {
  62         try {
  63             if (number++ > maxPerClassLoader || loader == null) {
  64                 loader = new GeneratingClassLoader(className);
  65                 count = 50;
  66                 number = 0;
  67             }
  68             return loader.loadClass(getNewName());
  69         } catch (ClassNotFoundException e) {
  70             throw new RuntimeException(e);
  71         }
  72     }
  73 }