1. /*
  2. * The Apache Software License, Version 1.1
  3. *
  4. *
  5. * Copyright (c) 1999-2002 The Apache Software Foundation. All rights
  6. * reserved.
  7. *
  8. * Redistribution and use in source and binary forms, with or without
  9. * modification, are permitted provided that the following conditions
  10. * are met:
  11. *
  12. * 1. Redistributions of source code must retain the above copyright
  13. * notice, this list of conditions and the following disclaimer.
  14. *
  15. * 2. Redistributions in binary form must reproduce the above copyright
  16. * notice, this list of conditions and the following disclaimer in
  17. * the documentation and/or other materials provided with the
  18. * distribution.
  19. *
  20. * 3. The end-user documentation included with the redistribution,
  21. * if any, must include the following acknowledgment:
  22. * "This product includes software developed by the
  23. * Apache Software Foundation (http://www.apache.org/)."
  24. * Alternately, this acknowledgment may appear in the software itself,
  25. * if and wherever such third-party acknowledgments normally appear.
  26. *
  27. * 4. The names "Xerces" and "Apache Software Foundation" must
  28. * not be used to endorse or promote products derived from this
  29. * software without prior written permission. For written
  30. * permission, please contact apache@apache.org.
  31. *
  32. * 5. Products derived from this software may not be called "Apache",
  33. * nor may "Apache" appear in their name, without prior written
  34. * permission of the Apache Software Foundation.
  35. *
  36. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  37. * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  38. * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  39. * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  40. * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  41. * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  42. * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  43. * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  44. * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  45. * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  46. * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  47. * SUCH DAMAGE.
  48. * ====================================================================
  49. *
  50. * This software consists of voluntary contributions made by many
  51. * individuals on behalf of the Apache Software Foundation and was
  52. * originally based on software copyright (c) 1999, International
  53. * Business Machines, Inc., http://www.apache.org. For more
  54. * information on the Apache Software Foundation, please see
  55. * <http://www.apache.org/>.
  56. */
  57. package com.sun.org.apache.xerces.internal.dom;
  58. /** Internal class LCount is used to track the number of
  59. listeners registered for a given event name, as an entry
  60. in a global hashtable. This should allow us to avoid generating,
  61. or discard, events for which no listeners are registered.
  62. ***** There should undoubtedly be methods here to manipulate
  63. this table. At the moment that code's residing in NodeImpl.
  64. Move it when we have a chance to do so. Sorry; we were
  65. rushed.
  66. ***** Also, I'm currently asking "are there any listeners"
  67. by testing captures+bubbles+defaults =? 0. It would probably
  68. make sense to have a separate "total" field, calculated at
  69. add/remove, to save a few cycles during dispatch. Fix.
  70. ???? CONCERN: Hashtables are known to be "overserialized" in
  71. current versions of Java. That may impact performance.
  72. ???? CONCERN: The hashtable should probably be a per-document object.
  73. Finer granularity would be even better, but would cost more cycles to
  74. resolve and might not save enough event traffic to be worth the investment.
  75. */
  76. /**
  77. * @version $Id: LCount.java,v 1.6 2003/05/08 19:52:40 elena Exp $
  78. */
  79. class LCount
  80. {
  81. static java.util.Hashtable lCounts=new java.util.Hashtable();
  82. public int captures=0,bubbles=0,defaults=0;
  83. static LCount lookup(String evtName)
  84. {
  85. LCount lc=(LCount)lCounts.get(evtName);
  86. if(lc==null)
  87. lCounts.put(evtName,(lc=new LCount()));
  88. return lc;
  89. }
  90. } // class LCount