Eliminating superfluous namespace declarations and undeclaring default namespaces in XML serialization processing

• US 7,120,864 B2
• Filed: 01/27/2004
• Issued: 10/10/2006
• Est. Priority Date: 01/27/2004
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Zhang, Guogen, Huang, Yue, Cu, Jason Alexander, Cai, Mengchu
• Primary Examiner(s): Hong, Stephen
• Assistant Examiner(s): QUELER, ADAM M
• Application Number:
  US10/766,764
• Publication Number:
  US 20050166140A1
• Time in Patent Office: 987 Days
• Field of Search: 715/513, 707/3, 707/4
• US Class Current: 715/234
• CPC Class Codes: G06F 16/838 Presentation of query results

Abstract

In one embodiment, at least a portion of an object model having at least one namespace is serialized. An ancestor namespace is searched for based on a current namespace declaration. The ancestor namespace is associated with an ancestor prefix and an ancestor uniform resource indicator (URI). The current namespace is associated with a current prefix and current URI. The search is performed to find an ancestor prefix matches the current prefix. When the current namespace is an implicit no default namespace and the ancestor namespace is an explicit default namespace based on, at least in part, the ancestor prefix, a serialized namespace declaration is generated for the current namespace.

Claims

1. A method of performing serialization of at least a portion of an object model comprising at least one namespace, comprising:

preprocessing a query to identify any implicit no default namespaces, wherein the object model is associated with the query;

searching for an ancestor namespace based on a current namespace, the ancestor namespace being associated with an ancestor prefix and an ancestor uniform resource identifier (URI), the current namespace being associated with a current prefix and current URI, such that the ancestor prefix matches the current prefix; and

when the current namespace is an implicit no default namespace and the ancestor namespace is an explicit default namespace based on, at least in part, the ancestor prefix, generating a serialized namespace declaration for the current namespace.

2. The method of claim 1 wherein the serialized namespace declaration is a serialized XML namespace declaration.

3. The method of claim 1 wherein a stack stores the ancestor namespaces, and said searching searches the stack for the ancestor prefix, and further comprising:

pushing the current prefix and current URI onto the stack.

4. The method of claim 1 further comprising:

when no ancestor namespace has an ancestor prefix that matches the current prefix, or when an ancestor namespace matches the current prefix and the ancestor URI is different from the current URI, generating a serialized namespace declaration for the current namespace.

5. The method of claim 1 wherein said generating generates the serialized namespace declaration when the implicit no default namespace is not a top constructor at the top query block, wherein the serialized namespace declaration is a no default namespace.

6. The method of claim 1 wherein the object model comprises at least one element, and a current tagging template represents the element, the tagging template having a pointer to a previous namespace declaration in an ancestor tagging template, wherein said searching searches for the ancestor namespace using the pointer.

7. The method of claim 6 wherein the tagging template further comprises an implicit-no-default indicator to indicate that a namespace declaration is implicit no default, and wherein said generating generates the serialized namespace declaration for the implicit no default namespace when the implicit-no-default indicator indicates that the current namespace is implicit no default.

8. The method of claim 1 further comprising:

hashing the current prefix to an index of a hash anchor array, wherein said searching accesses the hash anchor array for the ancestor namespace.

9. The method of claim 1 further comprising:

passing a template-chaining data structure comprising a pointer to a previous template-chaining data structure and also comprising a pointer to a namespace of a template, wherein said searching uses said template-chaining data structure to find the ancestor namespace declaration.

10. A computer readable medium embodying one or more instructions executable by a computer for performing a method of serializing at least a portion of an object model comprising at least one namespace, the method comprising:

preprocessing a query to identify any implicit no default namespaces, wherein the object model is associated with the query;

searching for an ancestor namespace based on a current namespace, the ancestor namespace being associated with an ancestor prefix and an ancestor uniform resource identifier (URI), the current namespace being associated with a current prefix and current URI, such that the ancestor prefix matches the current prefix; and

when the current namespace is an implicit no default namespace and the ancestor namespace is an explicit default namespace based on, at least in part, the ancestor prefix, generating a serialized namespace declaration for the current namespace.

11. The computer readable medium of claim 10 wherein the serialized namespace declaration is a serialized XML namespace declaration.

12. The computer readable medium of claim 10 wherein a stack stores the ancestor namespaces, said method further comprising:

pushing the current prefix and URI onto the stack, wherein said searching searches the stack for the ancestor prefix.

13. The computer readable medium of claim 10, said method further comprising:

when no ancestor namespace has an ancestor prefix that matches the current prefix, or when an ancestor namespace matches the current prefix and the ancestor URI is different from the current URI, generating a serialized namespace declaration for the current namespace.

14. The computer readable medium of claim 10 wherein said generating generates the serialized namespace declaration when the implicit no default namespace is not a top constructor at a top query block, wherein the serialized namespace declaration is a no default namespace.

15. The computer readable medium of claim 10 wherein the object model comprises at least one element, and a current tagging template represents the element, the tagging template having a pointer to a previous namespace declaration in an ancestor tagging template, wherein said searching searches for the ancestor namespace using the pointer.

16. The computer readable medium of claim 15 wherein the tagging template further comprises an implicit-no-default indicator to indicate that a namespace is implicit no default, further comprising determining whether the current namespace is implicit no default based on the implicit-no-default indicator.

17. The computer readable medium of claim 10, said method further comprising:

hashing the current prefix to an index of a hash anchor array, wherein said searching accesses the hash anchor array for the ancestor namespace.

18. The computer readable medium of claim 10, said method further comprising:

passing a current template-chaining data structure comprising a pointer to a previous template-chaining data structure and also comprising a pointer to the namespace declaration of a template, wherein said searching uses said current template-chaining data structure to find the ancestor namespace declaration.

19. An apparatus for performing serialization of at least a portion of an object model comprising at least one namespace, comprising:

a processor; and

a memory storing one or more instructions that cause the processor to;

preprocess a query to identify any implicit no default namespaces, wherein the object model is associated with the query;

search for an ancestor namespace based on a current namespace, the ancestor namespace being associated with an ancestor prefix and an ancestor uniform resource identifier (URI), the current namespace declaration being associated with a current prefix and current URI, such that the ancestor prefix matches the current prefix; and

when the current namespace is an implicit no default namespace and the ancestor namespace is an explicit default namespace based on, at least in part, the ancestor prefix, generate a serialized namespace declaration for the current namespace.

20. The apparatus of claim 19 wherein the serialized namespace declaration is a serialized XML namespace declaration.

21. The apparatus of claim 19 wherein a stack stores the ancestor namespaces, and further comprising one or more instructions that:

push the current prefix and URI onto the stack, wherein said one or more instructions that cause the processor to search searches the stack for the ancestor prefix.

22. The apparatus of claim 19 further comprising one or more instructions that:

when no ancestor namespace has an ancestor prefix that matches the current prefix, or when an ancestor namespace matches the current prefix and the ancestor URI is different from the current URI, generate the serialized namespace declaration for the current namespace.

23. The apparatus of claim 19:

wherein said one or more instructions that cause the processor to generate the serialized namespace declaration are performed when the implicit no default namespace is not a top constructor at a top query block, wherein the serialized namespace declaration is no default namespace.

24. The apparatus of claim 19 wherein the object model comprises at least one element, and a current tagging template represents the element, the tagging template having a pointer to a previous namespace declaration in an ancestor tagging template, wherein said one or more instructions that cause the processor to search searches for the ancestor namespace using the pointer.

25. The apparatus of claim 24 wherein the tagging template further comprises an implicit-no-default indicator to indicate that a namespace is implicit no default, further comprising one or more instructions that:

determine whether a namespace is implicit no default based on the implicit-no-default indicator.

26. The apparatus of claim 19 further comprising one or more instructions that:

hash the current prefix to an index of a hash anchor array, wherein said one or more instructions that cause the processor to search accesses the hash anchor array for the ancestor namespace.

27. The apparatus of claim 19 further comprising one or more instructions that:

pass a template-chaining data structure comprising a pointer to a previous template-chaining data structure and also comprising a pointer to the namespace of a template, wherein said one or more instructions that cause the processor to search searches using said template-chaining data structure to find the ancestor namespace declaration.