Version-insensitive serialization and deserialization of program objects

• US 20040167937A1
• Filed: 04/29/2003
• Published: 08/26/2004
• Est. Priority Date: 02/26/2003
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Cheung, Kit Man, Kohlmann, Peter W., Xu, Theresa, Tassi, Belal A., Sirois, Eric A., Mezofenyi, Mark, Lipford, Gordon D.
• Application Number:
  US10/426,521
• Publication Number:
  US 20040167937A1
• Time in Patent Office: Days
• US Class Current: 707/203
• CPC Class Codes: G06F 16/289 Object oriented databases
• CPC Class Codes: G06F 9/4493 Object persistence

Abstract

A method for serializing and deserializing program objects that is versioning sensitive. A program object is serialized into a persistent object by saving only those data fields that contain non-default data. The persistent object is deserialized to be used by a deserializing application by first creating a blank program object of the same version as the deserializing application and then populating it with the non-default data stored in the persistent object. The version of the deserializing application need not be the same as the version of the serializing application.

Claims

1. A method for reconstituting a program object from a persistent object using a computer system, said persistent object being stored on a storage media, said persistent object including a program object identification and field information, said field information including at least one field name and corresponding field data for each field name, the method comprising the steps of:

(a) parsing said persistent object to obtain said program object identification and to obtain said field names and their corresponding field data;

(b) creating a blank program object based upon said program object identification, said blank program object having a set of fields, each blank object field having a blank object field name and a blank object field data location, wherein said blank object field data locations are initialized with default values; and

(c) searching said blank program object for a matching blank object field name for each obtained field name from said persistent object, and if said matching blank object field name is found, copying said corresponding field data for said obtained field name into said blank object field location corresponding to said matching blank object field name.

2. The method claimed in claim 1, wherein said step of creating includes searching a set of known program object IDs to find one of said known program object IDs that matches the obtained program object identification.

3. The method claimed in claim 2, further including a step of generating an error if no known program object ID is located that matches the obtained program object identification.

4. The method claimed in claim 1, wherein said persistent object includes a serialization of an initial program object and said program object identification includes a class name for an initial class defining said initial program object.

5. The method claimed in claim 4, wherein said blank program object is defined by a different class having said class name, wherein said different class and said initial class are different versions of the same class.

6. The method claimed in claim 5, wherein said different class is an earlier version of said same class than said initial class.

7. The method claimed in claim 5, wherein said different class is a later version of said same class than said initial class.

8. The method claimed in claim 1, wherein said corresponding field data includes only non default values.

9. The method claimed in claim 8, wherein said default values and said non-default values are defined by a programming language.

10. The method claimed in claim 8, wherein said default values include an integer value of zero, a Boolean value of false, and a float value of zero.

11. The method claimed in claim 1, wherein said persistent object includes a file.

12. The method claimed in claim 11, wherein said file includes an XML file.

13. The method claimed in claim 1, further including a step of generating an error if said matching blank object field name is not found.

14. The method claimed in claim 1, wherein, once all of said corresponding field data is copied into said blank program object, said blank program object is said reconstituted program object, and further including a step of passing said reconstituted program object to an application.

15. The method claimed in claim 1, further including, prior to said step of parsing, a step of retrieving the persistent object from said storage media.

16. The method claimed in claim 1, wherein said persistent object is created by a serializing application and said blank program object is created by a deserializing application, wherein said serializing application and said deserializing application are different versions of the same application.

17. The method claimed in claim 16, wherein said persistent object includes the serialization of an initial program object, said initial program object is an object defined by the version of said serializing application, and said blank program object is an object defined by the version of said deserializing application.

18. The method claimed in claim 1, further including, prior to said step of parsing, a step of serializing an initial program object to create said persistent object.

19. The method claimed in claim 18, wherein said initial program object includes initial field names and corresponding initial field data, and said step of serializing includes the steps of reading said initial field names and said corresponding initial field data, and, for each initial field name, determining whether said corresponding initial field data includes non-default data, and, if said corresponding initial field data is non-default data, writing said initial field name and said corresponding initial field data to said persistent object.

20. A method of serializing an initial program object using a computer system, said initial program object including initial field names and corresponding initial field data, said initial program object further including an object identifier, wherein said method comprises the steps of:

(a) creating a persistent object;

(b) writing a program object identification to said persistent object based upon said object identifier; and

(c) determining whether said corresponding initial field data includes non-default data for each initial field name, and, if said corresponding initial field data is non-default data, writing said initial field name and said corresponding initial field data to said persistent object.

21. The method claimed in claim 20, wherein said object identifier includes a class name corresponding to a class definition from which said initial program object was created.

22. The method claimed in claim 20, wherein said persistent object includes a file.

23. The method claimed in claim 22, wherein said file includes an XML file.

24. The method claimed in claim 20, wherein said non-default values are defined by a programming language.

25. The method claimed in claim 20, further including the step of storing said persistent object on a storage media.

26. A computer program product having a computer readable medium tangibly embodying computer executable instructions for directing a data processing system to reconstitute a program object from a persistent object using a computer system, said persistent object being stored on a storage media, said persistent object including a program object identification and field information, said field information including at least one field name and corresponding field data for each field name, the computer executable instructions comprising:

(a) computer executable instructions for directing the data processing system to parse said persistent object to obtain said program object identification and to obtain said field names and their corresponding field data;

(b) computer executable instructions for directing the data processing system to create a blank program object based upon said program object identification, said blank program object having a set of fields, each blank object field having a blank object field name and a blank object field data location, wherein said blank object field data locations are initialized with default values; and

(c) computer executable instructions for directing the data processing system to search said blank program object for a matching blank object field name for each obtained field name form said persistent object, and if said matching blank object field name is found, copy said corresponding field data for said obtained field name into said blank object field location corresponding to said matching blank object field name.

27. The computer program product claimed in claim 26, wherein said computer executable instructions for directing the data processing system to create include directing the data processing system to search a set of known program object IDs to find one of said known program object IDs that matches the obtained program object identification.

28. The computer program product claimed in claim 27, further including computer executable instructions for directing the data processing system to generate an error if no known program object ID is located that matches the obtained program object identification.

29. The computer program product claimed in claim 26, wherein said persistent object includes a serialization of an initial program object and said program object identification includes a class name for an initial class defining said initial program object.

30. The computer program product claimed in claim 29, wherein said blank program object is defined by a different class having said class name, wherein said different class and said initial class are different versions of the same class.

31. The computer program product claimed in claim 30, wherein said different class is an earlier version of said same class than said initial class.

32. The computer program product claimed in claim 30, wherein said different class is a later version of said same class than said initial class.

33. The computer program product claimed in claim 26, wherein said corresponding field data includes only non-default values.

34. The computer program product claimed in claim 33, wherein said default values and said non-default values are defined by a programming language.

35. The computer program product claimed in claim 33, wherein said default values include an integer value of zero, a Boolean value of false, and a float value of zero.

36. The computer program product claimed in claim 26, wherein said persistent object includes a file.

37. The computer program product claimed in claim 36, wherein said file includes an XML file.

38. The computer program product claimed in claim 26, further including computer executable instructions for directing the data processing system to generate an error if said matching blank object field name is not found.

39. The computer program product claimed in claim 26, wherein, once all of said corresponding field data is copied into said blank program object, said blank program object is said reconstituted program object, and further including computer executable instructions directing the data processing system to pass said reconstituted program object to an application.

40. The computer program product claimed in claim 26, further including computer executable instructions for directing the data processing system to retrieve the persistent object from said storage media.

41. The computer program product claimed in claim 26, wherein said persistent object is created by a serializing application and said blank program object is created by a deserializing application, wherein said serializing application and said deserializing application are different versions of the same application.

42. The computer program product claimed in claim 41, wherein said persistent object includes the serialization of an initial program object, said initial program object is an object defined by the version of said serializing application, and said blank program object is an object defined by the version of said deserializing application.

43. The computer program product claimed in claim 26, further including computer executable instructions for directing the data processing system to serialize an initial program object to create said persistent object.

44. The computer program product claimed in claim 43, wherein said initial program object includes initial field names and corresponding initial field data, and said computer executable instructions for directing the data processing system to serialize includes instructions for directing the data processing system to read said initial field names and said corresponding initial field data, and, for each initial field name, determine whether said corresponding initial field data includes non default data, and, if said corresponding initial field data is non-default data, write said initial field name and said corresponding initial field data to said persistent object.

45. A computer program product having a computer readable medium tangibly embodying computer executable instructions for directing a data processing system to serialize an initial program object using a computer system, said initial program object including initial field names and corresponding initial field data, said initial program object further including an object identifier, wherein said computer executable instructions comprise:

(a) computer executable instructions for directing the data processing system to create a persistent object;

(b) computer executable instructions for directing the data processing system to write a program object identification to said persistent object based upon said object identifier; and

(c) computer executable instructions for directing the data processing system to determine whether said corresponding initial field data includes non-default data for each initial field name, and, if said corresponding initial field data is non-default data, write said initial field name and said corresponding initial field data to said persistent object.

46. The computer program product claimed in claim 45, wherein said object identifier includes a class name corresponding to a class definition from which said initial program object was created.

47. The computer program product claimed in claim 45, wherein said persistent object includes a file.

48. The computer program product claimed in claim 47, wherein said file includes an XML file.

49. The computer program product claimed in claim 45, wherein said non-default values are defined by a programming language.

50. The computer program product claimed in claim 45, further including computer executable instructions for directing the data processing system to store said persistent object on a storage media.

51. A data processing system for reconstituting a program object from a persistent object using a computer system, said persistent object being stored on a storage media, said persistent object including a program object identification and field information, said field information including at least one field name and corresponding field data for each field name, the data processing system comprising:

(a) means for parsing said persistent object to obtain said program object identification and to obtain said field names and their corresponding field data;

(b) means for creating a blank program object based upon said program object identification, said blank program object having a set of fields, each blank object field having a blank object field name and a blank object field data location, wherein said blank object field data locations are initialized with default values; and

(c) means for searching said blank program object for a matching blank object field name for each obtained field name from said persistent object, and if said matching blank object field name is found, copying said corresponding field data for said obtained field name into said blank object field location corresponding to said matching blank object field name.

52. The data processing system claimed in claim 51, wherein said means for creating includes means for searching a set of known program object IDs to find one of said known program object IDs that matches the obtained program object identification.

53. The data processing system claimed in claim 52, further including means for generating an error if no known program object ID is located that matches the obtained program object identification.

54. The data processing system claimed in claim 51, wherein said persistent object includes a serialization of an initial program object and said program object identification includes a class name for an initial class defining said initial program object.

55. The data processing system claimed in claim 54, wherein said blank program object is defined by a different class having said class name, wherein said different class and said initial class are different versions of the same class.

56. The method claimed in claim 55, wherein said different class is an earlier version of said same class than said initial class.

57. The data processing system claimed in claim 55, wherein said different class is a later version of said same class than said initial class.

58. The data processing system claimed in claim 51, wherein said corresponding field data includes only non-default values.

59. The data processing system claimed in claim 58, wherein said default values and said non default values are defined by a programming language.

60. The data processing system claimed in claim 58, wherein said default values include an integer value of zero, a Boolean value of false, and a float value of zero.

61. The data processing system claimed in claim 51, wherein said persistent object includes a file.

62. The data processing system claimed in claim 61, wherein said file includes an XML file.

63. The data processing system claimed in claim 51, further including means for generating an error if said matching blank object field name is not found.

64. The data processing system claimed in claim 51, wherein, once all of said corresponding field data is copied into said blank program object, said blank program object is said reconstituted program object, and further including means for passing said reconstituted program object to an application.

65. The data processing system claimed in claim 51, further including means for retrieving the persistent object from said storage media.

66. The data processing system claimed in claim 51, wherein said persistent object is created by a serializing application and said blank program object is created by a deserializing application, wherein said serializing application and said deserializing application are different versions of the same application.

67. The data processing system claimed in claim 66, wherein said persistent object includes the serialization of an initial program object, said initial program object is an object defined by the version of said serializing application, and said blank program object is an object defined by the version of said deserializing application.

68. The data processing system claimed in claim 51, further including means for serializing an initial program object to create said persistent object.

69. The data processing system claimed in claim 68, wherein said initial program object includes initial field names and corresponding initial field data, and said means for serializing includes means for reading said initial field names and said corresponding initial field data, and, for each initial field name, determining whether said corresponding initial field data includes non-default data, and, if said corresponding initial field data is non-default data, writing said initial field name and said corresponding initial field data to said persistent object.

70. A data processing system for serializing an initial program object using a computer system, said initial program object including initial field names and corresponding initial field data, said initial program object further including an object identifier, wherein said data processing system comprises:

(a) means for creating a persistent object;

(b) means for writing a program object identification to said persistent object based upon said object identifier; and

(c) means for determining whether said corresponding initial field data includes non default data for each initial field name, and, if said corresponding initial field data is non default data, writing said initial field name and said corresponding initial field data to said persistent object.

71. The data processing system claimed in claim 70, wherein said object identifier includes a class name corresponding to a class definition from which said initial program object was created.

72. The data processing system claimed in claim 70, wherein said persistent object includes a file.

73. The data processing system claimed in claim 72, wherein said file includes an XML file.

74. The data processing system claimed in claim 70, wherein said non-default values are defined by a programming language.

75. The data processing system claimed in claim 70, further including means for storing said persistent object on a storage media.

76. An article including a computer readable signal bearing medium, and including means in the medium for directing a data processing system to reconstitute a program object from a persistent object using a computer system, said persistent object being stored on a storage media, said persistent object including a program object identification and field information, said field information including at least one field name and corresponding field data for each field name, said article comprising:

means in the medium for parsing said persistent object to obtain said program object identification and to obtain said field names and their corresponding field data;

means in the medium for creating a blank program object based upon said program object identification, said blank program object having a set of fields, each blank object field having a blank object field name and a blank object field data location, wherein said blank object field data locations are initialized with default values; and

means in the medium for searching said blank program object for a matching blank object field name for each obtained field name from said persistent object, and if said matching blank object field name is found, copying said corresponding field data for said obtained field name into said blank object field location corresponding to said matching blank object field name.

77. The article claimed in claim 76, wherein said means in the medium for creating includes searching a set of known program object IDs to find one of said known program object IDs that matches the obtained program object identification.

78. The article claimed in claim 77, wherein said article further comprises means in the medium for generating an error if no known program object ID is located that matches the obtained program object identification.

79. The article claimed in claim 76, wherein said persistent object includes a serialization of an initial program object and said program object identification includes a class name for an initial class defining said initial program object.

80. The article claimed in claim 79, wherein said blank program object is defined by a different class having said class name, wherein said different class and said initial class are different versions of the same class.

81. The article claimed in claim 80, wherein said different class is an earlier version of said same class than said initial class.

82. The article claimed in claim 80, wherein said different class is a later version of said same class than said initial class.

83. The article claimed in claim 76, wherein said corresponding field data includes only non default values.

84. The article claimed in claim 83, wherein said default values and said non-default values are defined by a programming language.

85. The article claimed in claim 83, wherein said default values include an integer value of zero, a Boolean value of false, and a float value of zero.

86. The article claimed in claim 76, wherein said persistent object includes a file.

87. The article claimed in claim 86, wherein said file includes an XML file.

88. The article claimed in claim 76, further comprising means in the medium for generating an error if said matching blank object field name is not found.

89. The article claimed in claim 76, wherein, once all of said corresponding field data is copied into said blank program object, said blank program object is said reconstituted program object, and wherein said method further includes a step of passing said reconstituted program object to an application.

90. The article claimed in claim 76, wherein said article further comprises means in the medium for retrieving the persistent object from said storage media prior to said step of parsing.

91. The article claimed in claim 76, wherein said persistent object is created by a serializing application and said blank program object is created by a deserializing application, wherein said serializing application and said deserializing application are different versions of the same application.

92. The article claimed in claim 91, wherein said persistent object includes the serialization of an initial program object, said initial program object is an object defined by the version of said serializing application, and said blank program object is an object defined by the version of said deserializing application.

93. The article claimed in claim 76, wherein said article further comprises means in the medium for serializing an initial program object to create said persistent object prior to said step of parsing.

94. The article claimed in claim 93, wherein said initial program object includes initial field names and corresponding initial field data, and said means in the medium for serializing includes reading said initial field names and said corresponding initial field data, and, for each initial field name, determining whether said corresponding initial field data includes non-default data, and, if said corresponding initial field data is non-default data, writing said initial field name and said corresponding initial field data to said persistent object.

95. An article including a computer readable signal bearing medium, and including means in the medium for directing a data processing system to serialize an initial program object using a computer system, said initial program object including initial field names and corresponding initial field data, said initial program object further including an object identifier, said article comprising:

means in the medium for creating a persistent object;

means in the medium for writing a program object identification to said persistent object based upon said object identifier; and

means in the medium for determining whether said corresponding initial field data includes non-default data for each initial field name, and, if said corresponding initial field data is non-default data, writing said initial field name and said corresponding initial field data to said persistent object.

96. The article claimed in claim 95, wherein said object identifier includes a class name corresponding to a class definition from which said initial program object was created.

97. The article claimed in claim 95, wherein said persistent object includes a file.

98. The article claimed in claim 97, wherein said file includes an XML file.

99. The article claimed in claim 96, wherein said non-default values are defined by a programming language.

100. The article claimed in claim 96, wherein said article further comprises means in the medium for storing said persistent object on a storage media.