Method and system to handle context of interpretation in a document processing language

• US 5,499,329 A
• Filed: 07/02/1993
• Issued: 03/12/1996
• Est. Priority Date: 04/30/1992
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Original Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Inventors: Motoyama, Tetsuro, Chang, Yueh-Lin
• Primary Examiner(s): Herndon, Heather R.
• Assistant Examiner(s): Fetting, Anton W.
• Application Number:
  US08/087,571
• Time in Patent Office: 984 Days
• Field of Search: 395/145, 395/148, 395/162, 395/116, 364/419.07, 364/419.08, 364/419.11, 364/419.13, 364/419.12, 364/419.19
• US Class Current: 715/236
• CPC Class Codes: G06F 3/1297 Printer code translation, conversion, emulation, compression; Configuration of printer parameters
• CPC Class Codes: G06F 40/103 Formatting, i.e. changing of presentation of documents automatic justification G06F40/189; automatic line break hyphenation G06F40/191
• CPC Class Codes: G06F 40/151 Transformation
• CPC Class Codes: G06F 40/154 Tree transformation for tree-structured or markup documents, e.g. XSLT, XSL-FO or stylesheets
• CPC Class Codes: G06F 40/237 Lexical tools
• CPC Class Codes: G06K 15/00 Arrangements for producing a permanent visual presentation of the output data , e.g. computer output printersprinting or plotting combined with another operation, e.g. with conveying, G06K17/00
• CPC Class Codes: G06K 15/1828 characterized by the kind of storage accessed
• CPC Class Codes: G06K 15/1849 using an intermediate representation, e.g. a list of graphical primitives
• CPC Class Codes: G06K 2215/0011 characterised by a particular command or data flow, e.g. Page Description Language, configuration commands

Abstract

A method and apparatus for processing the hierarchical structure of page description language. Each structure level of the document causes the creation of a prologue data structure which is used to keep track of system parameters. As content portions of the document are being processed, a current context of interpretation data structure is created which is also used to store parameters of the system. The prologue data structure and the current context of interpretation data structure contain pointers relating to context dictionaries, a user dictionary, and a state variable table. The dictionaries are kept track of by using a context stack made up by linked list data structures. It is possible to modify the search order of the context dictionaries by structure or content portions of the document and the linked list data structures keep track of whether the dictionaries were created using the content portions or structure portions.

Claims

1. A computer implemented method for processing a hierarchically structured document, comprising the steps of:

creating a first data structure having a first set of information;

creating a first reference to the first data structure, said first reference to the first data structure being associated with a structure portion of a predetermined hierarchical level of the document;

creating, for said predetermined hierarchical level of the document when a content portion of said predetermined hierarchical level is processed, a second data structure which has a second reference thereto and copying the first set of information to a second set of information of the second data structure;

processing said content portion of said predetermined hierarchical level using the second reference to said second set of information;

determining if processing of content for said predetermined hierarchical level is finished;

processing a structure portion of a first subsequent hierarchical level, wherein said first subsequent hierarchical level is lower in the hierarchical structure of the document than the predetermined hierarchical level;

copying the first reference to a third reference associated with the structure portion of the first subsequent hierarchical level;

processing a structure portion of a second subsequent hierarchical level, wherein said second subsequent hierarchical level is lower in the hierarchical structure of the document than the first subsequent hierarchical level;

creating, for said second subsequent hierarchical level of the document when a content portion of said second subsequent hierarchical level is processed, a third data structure referenced by a fourth reference and copying the set of information referred to by the third reference to a third set of information of the third data structure;

processing said content portion of said second subsequent hierarchical level using said third set of information;

determining if processing of said content portion of said second subsequent hierarchical level is finished; and

copying the fourth reference to the third reference, when said processing of said content portion of said second subsequent hierarchical level is determined to be finished.

2. The method according to claim 1, further comprising the step of:

creating an entry in a stack for the predetermined hierarchical and the first subsequent hierarchical levels of the document, each entry in the stack including a reference to a set of references corresponding to structure of a corresponding hierarchical level and used during processing of the corresponding hierarchical level, and including a reference to a set of references corresponding to content of a corresponding hierarchical level and used during processing of a content portion of the corresponding hierarchical level.

3. A method according to claim 1, wherein said hierarchically structured document is a document which conforms to rules of a Standard Page Description Language.

4. A method according to claim 1, wherein:

said step of copying the fourth reference to the third reference copies a reference which is one of a reference to a state variable table and a reference to a dictionary which includes key-value pairs.

5. A computer implemented method for processing a hierarchically structured document, comprising the steps of:

creating a first data structure having a first set of information;

creating a first reference to the first data structure, said first reference to the first data structure being associated with a structure portion of a predetermined hierarchical level of the document;

creating, for said predetermined hierarchical level of the document when a content portion of said predetermined hierarchical level is processed, a second data structure having a second reference thereto and copying the first set of information to a second set of information of the second data structure;

processing a structure portion of a subsequent hierarchical level, wherein said subsequent hierarchical level is lower in the hierarchical structure of the document than the predetermined hierarchical level;

determining if processing of content for said predetermined hierarchical level is in process;

copying the second reference to a third reference associated with structure of the subsequent hierarchical level, when said processing of content for said predetermined hierarchical level is determined to be in process;

copying the first reference to the first data structure to the third reference associated with the structure of the subsequent hierarchical level, when said processing of content for said predetermined hierarchical level is determined not to be in process;

creating, for said subsequent hierarchical level of the document when a content portion of said subsequent hierarchical level is processed, a third data structure referenced by a fourth reference and copying the set of information referred to by the third reference to a third set of information of the third data structure; and

processing said content portion of said subsequent hierarchical level using said third set of information; and

continuing processing of said content portion of said predetermined hierarchical level after processing of said content portion of said subsequent hierarchical level is complete, using said second reference to said second data structure containing said second set of information, when said processing of content for said predetermined hierarchical level is determined to be in process.

6. A method according to claim 5, wherein said hierarchically structured document is a document which conforms to rules of a Standard Page Description Language.

7. An apparatus for processing a hierarchically structured document, comprising:

means for creating a first data structure having a first set of information;

means for creating a first reference to the first data structure, said first reference to the first data structure being associated with a structure portion of a predetermined hierarchical level of the document;

means for creating, for said predetermined hierarchical level of the document when a content portion of said predetermined hierarchical level is processed, a second data structure which has a second reference thereto and copying the first set of information to a second set of information of the second data structure;

means for processing said content portion of said predetermined hierarchical level using the second reference to said second set of information;

means for determining if processing of content for said predetermined hierarchical level is finished;

means for processing a structure portion of a first subsequent hierarchical level, wherein said first subsequent hierarchical level is lower in the hierarchical structure of the document than the predetermined hierarchical level;

means for copying the first reference to a third reference associated with the structure portion of the first subsequent hierarchical level;

means for processing a structure portion of a second subsequent hierarchical level, wherein said second subsequent hierarchical level is lower in the hierarchical structure of the document than the first subsequent hierarchical level;

means for creating, for said second subsequent hierarchical level of the document when a content portion of said second subsequent hierarchical level is processed, a third data structure referenced by a fourth reference and copying the set of information referred to by the third reference to a third set of information of the third data structure;

means for processing said content portion of said second subsequent hierarchical level using said third set of information;

means for determining if processing of said content portion of said second subsequent hierarchical level is finished; and

means for copying the fourth reference to the third reference, when said processing of said content portion of said second subsequent hierarchical level is determined to be finished.

8. The apparatus according to claim 7, further comprising:

means for creating an entry in a stack for the predetermined and the first subsequent hierarchical levels of the document, each entry in the stack including a reference to a set of references corresponding to structure of a corresponding hierarchical level and used during processing of the corresponding hierarchical level, and including a reference to a set of references corresponding to content of a corresponding hierarchical level and used during processing of a content portion of the corresponding hierarchical level.

9. The apparatus according to claim 7, wherein said hierarchically structured document is a document which conforms to rules of a Standard Page Description Language.

10. The apparatus according to claim 7, wherein:

said means for copying the fourth reference to the third reference copies a reference which is one of a reference to a state variable table and a reference to a dictionary which includes key-value pairs.

11. An apparatus for processing a hierarchically structured document, comprising:

means for creating a first data structure having a first set of information;

means for creating a first reference to the first data structure, said first reference to the first data structure being associated with a structure portion of a predetermined hierarchical level of the document;

means for creating, for said predetermined hierarchical level of the document when a content portion of said predetermined hierarchical level is processed, a second data structure having a second reference thereto and copying the first set of information to a second set of information of the second data structure;

means for processing a structure portion of a subsequent hierarchical level, wherein said subsequent hierarchical level is lower in the hierarchical structure of the document than the predetermined hierarchical level;

means for determining if processing of content for said predetermined hierarchical level is in process;

means for copying the second reference to a third reference associated with structure of the subsequent hierarchical level, when said processing of content for said predetermined hierarchical level is determined to be in process;

means for copying the first reference to the first data structure to the third reference associated with the structure of the subsequent hierarchical level, when said processing of content for said predetermined hierarchical level is determined not to be in process;

means for creating, for said subsequent hierarchical level of the document when a content portion of said subsequent hierarchical level is processed, a third data structure referenced by a fourth reference and copying the set of information referred to by the third reference to a third set of information of the third data structure;

means for processing said content portion of said subsequent hierarchical level using said third set of information; and

means for continuing processing of said content portion of said predetermined hierarchical level after processing of said content portion of said subsequent hierarchical level is complete, using said second reference to said second data structure containing said second set of information, when said processing of content for said predetermined hierarchical level is determined to be in process.

12. The apparatus according to claim 11, wherein said hierarchically structured document is a document which conforms to rules of a Standard Page Description Language.