Property bundles on a per instance basis

• US 7,725,878 B1
• Filed: 12/28/2001
• Issued: 05/25/2010
• Est. Priority Date: 05/12/2000
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Pitfield, David B., Long, David J.
• Primary Examiner(s): Dam; Tuan Q
• Assistant Examiner(s): DAO, THUY CHAN
• Application Number:
  US10/040,578
• Time in Patent Office: 3,070 Days
• Field of Search: 717/116, 707/102, 707/103
• US Class Current: 717/116
• CPC Class Codes: G06F 21/6209 to a single file or object, e.g. in a secure envelope, encrypted and accessed using a key, or with access control rules appended to the object itself
• CPC Class Codes: G06F 2221/2141 Access rights, e.g. capability lists, access control lists, access tables, access matrices
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: G06F 2221/2145 Inheriting rights or properties, e.g., propagation of permissions or restrictions within a hierarchy
• CPC Class Codes: G06F 2221/2149 Restricted operating environment
• CPC Class Codes: G06F 2221/2151 Time stamp
• CPC Class Codes: G06F 9/4492 Inheritance
• CPC Class Codes: H04L 63/102 Entity profiles

Abstract

A method and apparatus for associating methods or attributes on a per-instance basis is provided. One technique for providing “per-instance attributes” involves properties and property bundles. A second technique for providing “per-instance attributes” involves categories wherein the instance can be thought of as being “placed” into one or more categories. A technique for providing “per-instance methods” involves policies. In any of these techniques, providing per-instance properties may be used in any of the following ways: (1) different instances of the same class are associated with different properties where the properties are not in the class; and (2) two instances of two different classes are associated with the same property where the property is not in either of the two classes.

Claims

1. A method of implementing per-instance attributes, the method comprising computer-implemented steps of:

instantiating a first instance of a class and a second instance of said class, wherein said class includes a single-valued property attribute;

wherein both said first instance of said class and said second instance of said class include said single-valued property attribute;

assigning to said single-valued property attribute of said first instance a first value that associates a first set of one or more attributes with said first instance;

assigning to said single-valued property attribute of said second instance a second value that associates a second set of one or more attributes with said second instance;

wherein said first set of one or more attributes is different than said second set of one or more attributes;

wherein said first set of one or more attributes and said second set of one or more attributes are not included in said class or any superclass of said class;

wherein assigning said first value to said single-valued property attribute of said first instance does not cause any of said first set of one or more attributes to become attributes of said class or of any instance of said class other than said first instance;

wherein assigning said second value to said single-valued property attribute of said second instance does not cause any of said second set of one or more attributes to become attributes of said class or of any instance of said class other than said second instance;

wherein said steps of said method are performed by one or more computing devices.

2. The method of claim 1, wherein:

a first property class contains said first set of one or more attributes, wherein said first value references an instance of said first property class; and

a second property class contains said second set of one or more attributes, wherein said second value references an instance of said second property class; and

said first property class is different than said second property class.

3. The method of claim 1, wherein:

said first value references a first instance of a property bundle class, wherein one or more instances of a first set of one or more property classes include pointers to said first instance of said property bundle class, wherein said first set of one or more property classes include said first set of one or more attributes;

said second value references a second instance of said property bundle class, wherein one or more instances of a second set of one or more property classes include pointers to said second instance of said property bundle class, wherein said second set of one or more property classes include said second set of one or more attributes; and

said first set of one or more property classes are different than said second set of one or more property classes.

4. The method of claim 1, further comprising the steps of:

assigning a first set of one or more keys to said first set of one or more attributes, wherein said first set of one or more keys respectively identifies said first set of one or more attributes; and

assigning a second set of one or more keys to said second set of one or more attributes, wherein said second set of one or more keys respectively identifies said second set of one or more attributes.

5. The method of claim 4, wherein:

assigning said first set of one or more keys comprises receiving, from a user, first data that defines said first set of one or more keys; and

assigning said second set of one or more keys comprises receiving, from said user, second data that defines said second set of one or more keys.

6. The method of claim 4, wherein:

assigning said first set of one or more keys comprises invoking a method for each of said first set of one or more attributes.

7. The method of claim 1, wherein said class represents a file type in an extensible file system, and wherein:

said first instance of said class represents a first file of said file type, wherein said first file is associated, through the first value, with said first set of one or more attributes that do not belong to said file type; and

said second instance of said class represents a second file of said file type, wherein said second file is associated, through the second value, with said second set of one or more attributes that do not belong to said file type.

8. A method of implementing per-instance attributes, the method comprising computer-implemented steps of:

instantiating an instance of a class, wherein said class defines a first set of one or more attributes;

including, in the structure of said instance of said class, a table for storing data associated with a second set of one or more attributes, wherein, for each particular attribute of said second set of one or more attributes, said table includes a particular entry that comprises;

a first field for storing an identifier of said particular attribute; and

a second field for storing one or more data values of said particular attribute;

wherein said first set of one or more attributes defined in said class do not include said second set of one or more attributes;

wherein said second set of one or more attributes do not belong to said class or any superclass of said class;

wherein said steps of said method are performed by one or more computing devices.

9. The method of claim 8, wherein said identifier is an attribute name of said particular attribute.

10. The method of claim 8, wherein identifiers stored in said first field are designated as keys for locating entries in said table, and wherein said method further comprises steps of:

receiving a data value of a specific attribute of said second set of one or more attributes and a specific identifier that identifies said specific attribute;

using said specific identifier to locate in said table a specific entry that stores said specific attribute; and

without performing datatype checking on said data value, storing said data value in said specific entry.

11. The method of claim 8, wherein said table is a hash table, and wherein said method further comprises steps of:

receiving input that identifies a specific attribute of said second set of one or more attributes;

hashing said input to generate a hash key; and

using said hash key to locate in said hash table a specific entry that stores said specific attribute.

12. The method of claim 8, further comprising a step of adding a specific attribute to said second set of one or more attributes in response to an invocation of a method defined in said class.

13. The method of claim 12, wherein:

said invocation of said method includes a specific identifier by which said specific attribute will be identified; and

adding said specific attribute includes storing said specific identifier in said first field of a specific entry in said table.

14. A computer-readable storage medium storing one or more sequences of executable instructions for implementing per-instance attributes, which instructions, when executed by one or more processors, cause performance of steps comprising:

instantiating a first instance of a class and a second instance of said class, wherein said class includes a single-valued property attribute;

wherein both said first instance of said class and said second instance of said class include said single-valued property attribute;

assigning to said single-valued property attribute of said first instance a first value that associates a first set of one or more attributes with said first instance;

assigning to said single-valued property attribute of said second instance a second value that associates a second set of one or more attributes with said second instance;

wherein said first set of one or more attributes is different than said second set of one or more attributes;

wherein said first set of one or more attributes and said second set of one or more attributes are not included in said class or any superclass of said class;

wherein assigning said first value to said single-valued property attribute of said first instance does not cause any of said first set of one or more attributes to become attributes of said class or of any instance of said class other than said first instance; and

wherein assigning said second value to said single-valued property attribute of said second instance does not cause any of said second set of one or more attributes to become attributes of said class or of any instance of said class other than said second instance.

15. The computer-readable storage medium of claim 14, wherein:

a first property class contains said first set of one or more attributes, wherein said first value references an instance of said first property class; and

a second property class contains said second set of one or more attributes, wherein said second value references an instance of said second property class; and

said first property class is different than said second property class.

16. The computer-readable storage medium of claim 14, wherein:

said first value references a first instance of a property bundle class, wherein one or more instances of a first set of one or more property classes include pointers to said first instance of said property bundle class, wherein said first set of one or more property classes include said first set of one or more attributes;

said second value references a second instance of said property bundle class, wherein one or more instances of a second set of one or more property classes include pointers to said second instance of said property bundle class, wherein said second set of one or more property classes include said second set of one or more attributes; and

said first set of one or more property classes are different than said second set of one or more property classes.

17. The computer-readable storage medium of claim 14, wherein the one or more sequences of executable instructions further comprise instructions which, when executed by the one or more processors, cause performance of the steps of:

assigning a first set of one or more keys to said first set of one or more attributes, wherein said first set of one or more keys respectively identifies said first set of one or more attributes; and

assigning a second set of one or more keys to said second set of one or more attributes, wherein said second set of one or more keys respectively identifies said second set of one or more attributes.

18. The computer-readable storage medium of claim 17, wherein:

the instructions that cause performance of the step of assigning said first set of one or more keys comprise instructions which, when executed by the one or more processors, cause performance of the step of receiving, from a user, first data that defines said first set of one or more keys; and

the instructions that cause performance of the step of assigning said second set of one or more keys comprise instructions which, when executed by the one or more processors, cause performance of the step of receiving, from said user, second data that defines said second set of one or more keys.

19. The comnuter-readable storage medium of claim 17, wherein:

the instructions that cause performance of the step of assigning said first set of one or more keys comprise instructions which, when executed by the one or more processors, cause performance of the step of invoking a method for each of said first set of one or more attributes.

20. The computer-readable storage medium of claim 14, wherein said class represents a file type in an extensible file system, and wherein:

said first instance of said class represents a first file of said file type, wherein said first file is associated, through the first value, with said first set of one or more attributes that do not belong to said file type; and

said second instance of said class represents a second file of said file type, wherein said second file is associated, through the second value, with said second set of one or more attributes that do not belong to said file type.

21. A computer-readable storage medium storing one or more sequences of executable instructions for implementing per-instance attributes, which instructions, when executed by one or more processors, cause performance of steps comprising:

instantiating an instance of a class, wherein said class defines a first set of one or more attributes;

including, in the structure of said instance of said class, a table for storing data associated with a second set of one or more attributes, wherein, for each particular attribute of said second set of one or more attributes, said table includes a particular entry that comprises;

a first field for storing an identifier of said particular attribute; and

a second field for storing one or more data values of said particular attribute;

wherein said first set of one or more attributes defined in said class do not include said second set of one or more attributes; and

wherein said second set of one or more attributes do not belong to said class or any superclass of said class.

22. The computer-readable storage medium of claim 21, wherein said identifier is an attribute name of said particular attribute.

23. The computer-readable storage medium of claim 21, wherein identifiers stored in said first field are designated as keys for locating entries in said table, and wherein the one or more sequences of executable instructions further comprise instructions which, when executed by the one or more processors, cause performance of the steps of:

receiving a data value of a specific attribute of said second set of one or more attributes and a specific identifier that identifies said specific attribute;

using said specific identifier to locate in said table a specific entry that stores said specific attribute; and

without performing datatype checking on said data value, storing said data value in said specific entry.

24. The computer-readable storage medium of claim 21, wherein said table is a hash table, and wherein the one or more sequences of executable instructions further comprise instructions which, when executed by the one or more processors, cause performance of the steps of:

receiving input that identifies a specific attribute of said second set of one or more attributes;

hashing said input to generate a hash key; and

using said hash key to locate in said hash table a specific entry that stores said specific attribute.

25. The computer-readable storage medium of claim 21, wherein the one or more sequences of executable instructions further comprise instructions which, when executed by the one or more processors, cause performance of the step of adding a specific attribute to said second set of one or more attributes in response to an invocation of a method defined in said class.

26. The computer-readable storage medium of claim 25, wherein:

said invocation of said method includes a specific identifier by which said specific attribute will be identified; and

the instructions that cause performance of the step of adding said specific attribute include instructions which, when executed by the one or more processors, cause performance of the step of storing said specific identifier in said first field of a specific entry in said table.