/interpreter/tags/at2dist170907/src/edu/vub/at/actors/ATActorMirror.java

http://ambienttalk.googlecode.com/ · Java · 151 lines · 16 code · 14 blank · 121 comment · 0 complexity · 2917871cf170e20e431b5c769f14ee52 MD5 · raw file

  1. /**
  2. * AmbientTalk/2 Project
  3. * ATActorMirror.java created on Aug 21, 2006
  4. * (c) Programming Technology Lab, 2006 - 2007
  5. * Authors: Tom Van Cutsem & Stijn Mostinckx
  6. *
  7. * Permission is hereby granted, free of charge, to any person
  8. * obtaining a copy of this software and associated documentation
  9. * files (the "Software"), to deal in the Software without
  10. * restriction, including without limitation the rights to use,
  11. * copy, modify, merge, publish, distribute, sublicense, and/or
  12. * sell copies of the Software, and to permit persons to whom the
  13. * Software is furnished to do so, subject to the following
  14. * conditions:
  15. *
  16. * The above copyright notice and this permission notice shall be
  17. * included in all copies or substantial portions of the Software.
  18. *
  19. * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  20. * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  21. * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  22. * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  23. * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  24. * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  25. * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  26. * OTHER DEALINGS IN THE SOFTWARE.
  27. */
  28. package edu.vub.at.actors;
  29. import edu.vub.at.exceptions.InterpreterException;
  30. import edu.vub.at.objects.ATBoolean;
  31. import edu.vub.at.objects.ATClosure;
  32. import edu.vub.at.objects.ATObject;
  33. import edu.vub.at.objects.ATTypeTag;
  34. import edu.vub.at.objects.ATTable;
  35. import edu.vub.at.objects.grammar.ATSymbol;
  36. /**
  37. * The class ATActorMirror prescribes the minimal set of methods to be provided by the default
  38. * implementation of an actor mirror. Since new actor mirrors can be installed dynamically,
  39. * ATActorMirror defines the dependencies of the lexically scoped objects on the dynamic 'actor
  40. * context' to perform their duties. The hooks defined in this class relate to:
  41. *
  42. * <ul>
  43. * <li>Asynchronous message creation and sending to influence the communication protocol</li>
  44. * <li>Service advertising and requesting to influence the service discovery protocol</li>
  45. * <li>Mirror creation to provide support for true stratification</li>
  46. * <li>Actor protocol installation to deal with actor mirror interaction and to allow freezing
  47. * an actor with a given protocol</li>
  48. * </ul>
  49. *
  50. * @author smostinc
  51. */
  52. public interface ATActorMirror extends ATObject {
  53. /* ---------------------------------------------------
  54. * -- Language Construct to NATActorMirror Protocol --
  55. * --------------------------------------------------- */
  56. /**
  57. * Creates a first-class message in the language. Note that upon creation the
  58. * message does not have a receiver yet. This field will be set once the message
  59. * is actually being sent, a fact which can be intercepted by overriding the sendTo
  60. * base-level method.
  61. *
  62. * @param selector the name of the method to trigger remotely
  63. * @param arguments the actual arguments of the message
  64. * @param types the types with which the message will be born
  65. */
  66. public ATAsyncMessage base_createMessage(ATSymbol selector, ATTable arguments, ATTable types) throws InterpreterException;
  67. /**
  68. * Creates a mirror on the given object. This method serves as the 'mirror factory'
  69. * for the current actor.
  70. */
  71. public ATObject base_createMirror(ATObject onObject) throws InterpreterException;
  72. /**
  73. * This method implements the default asynchronous message sending semantics for
  74. * this particular actor. In addition to the ability to override the send meta-
  75. * operation on a single object to have specific adaptions, this hook allows the
  76. * programmer to modify the message sending semantics for all objects inside an
  77. * actor. The default implementation ensures the correct passing of messages when
  78. * they transgress the boundaries of the sending actor.
  79. *
  80. * @throws InterpreterException
  81. */
  82. public ATObject base_send(ATObject receiver, ATAsyncMessage message) throws InterpreterException;
  83. /**
  84. * This mechanism is the most basic mechanism to provide a service. It requires
  85. * a separate service description and an object offering the service. The return
  86. * value is a publication object which allows cancelling the service offer.
  87. */
  88. public ATObject base_provide(ATTypeTag topic, ATObject service) throws InterpreterException;
  89. /**
  90. * This mechanism is the most basic mechanism to require a service. The return
  91. * value is a subscription object which allows cancelling the service offer.
  92. * @param bool - if true, the subscription is permanent, if false, once the subscription
  93. * has been satisfied, it is automatically cancelled.
  94. */
  95. public ATObject base_require(ATTypeTag topic, ATClosure handler, ATBoolean bool) throws InterpreterException;
  96. /**
  97. * def oldprotocol := actor.install: newprotocol
  98. *
  99. * Installs a new meta-object protocol into this actor.
  100. *
  101. * @param protocol meta-level code that overrides an actor's MOP methods
  102. * @return the previously installed meta-object protocol
  103. */
  104. public ATObject base_install_(ATActorMirror protocol) throws InterpreterException;
  105. /* -------------------------------------
  106. * -- Object Passing Protocol Support --
  107. * ------------------------------------- */
  108. /**
  109. * This mechanism interacts with the built-in receptionists set of the actor to
  110. * produce a new far object reference to a local object. The created far object
  111. * is by no means unique within the actor that created it.
  112. *
  113. * Creating such far references is performed when passing objects by reference
  114. * in the meta_pass method of scoped objects such as closures, objects and fields.
  115. *
  116. * @param object the local object to be given a reference to
  117. * @return a newly created far object reference
  118. *
  119. * @see edu.vub.at.objects.ATObject#meta_pass(ATFarReference)
  120. */
  121. //public ATFarReference base_export(ATObject object) throws InterpreterException;
  122. /**
  123. * This mechanism interacts with the built-in receptionists set of the actor to
  124. * resolve far references (which were received as part of an async message). The
  125. * method returns a local object whenever the far object denotes an object
  126. * hosted by this actor.
  127. *
  128. * If the denoted object is not hosted by this actor, a far object (possibly but
  129. * not necessarily the passed one) is returned which is the local and unique
  130. * representative of the remote object. This object will contain the queue of
  131. * messages to be transmitted to the remote object.
  132. *
  133. * @param farReference the far reference to be resolved
  134. * @return a local object | a unique far reference for this actor
  135. */
  136. //public ATObject base_resolve(ATFarReference farReference) throws InterpreterException;
  137. }