System for selectively converting plurality of source data structures through corresponding source intermediate structures, and target intermediate structures into selected target structure

• US 5,119,465 A
• Filed: 06/19/1989
• Issued: 06/02/1992
• Est. Priority Date: 06/19/1989
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Digital Equipment Corporation (HP Inc.)
• Inventors: Jack, Martin L., Gumbel, Richard T.
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): Donaghue, L.
• Application Number:
  US07/368,716
• Time in Patent Office: 1,079 Days
• Field of Search: 364/200 MS File, 364/900 MS File
• US Class Current: 717/137
• CPC Class Codes: G06F 16/258 Data format conversion from or to a database
• CPC Class Codes: G06F 40/151 Transformation

Abstract

A data structure format conversion system comprising a front end converter, a back end converter, and a converter executive. The front end converter converts a source data structure in a source format to data in an intermediate format. The back end converter converts the data in the intermediate format to a target data structure in a target format. Finally, a converter executive controls the front end converter and back end converter to effect a conversion from the source data structure in the source format to the target data structure in the target format, through the intermediate format.

Claims

1. A data structure format conversion system comprising:

a front end converter for converting a source data structure in a source data format to a source domain intermediate structure;

a domain converter for converting the source domain intermediate structure to a target domain intermediate structure;

said domain converter including a domain conversion activation portion for establishing the domain converter as an intermediary when domain conversion is required between a selected front end converter and a selected back end converter;

a back end converter for converting the target domain intermediate structure to a target data structure in a target data format; and

a converter executive for controlling the front end converter, the domain converter, and the back end converter to effect a conversion from the source data structure in the source format to the target data structure in the target data format.

2. The data structure format conversion system as claimed in claim 1, wherein the converter executive further comprises:

a converter selection portion for selecting a front end converter from a plurality of front end converters, and for selecting a back end converter from a plurality of back end converters.

3. The data structure format conversion system as claimed in claim 1 in which the back end converter operates iteratively in connection with sequential portions of the source data structure, the back end converter iteratively generating data requests which enable the converter executive to, in turn, enable the front end converter to perform a conversion operation in connection with a next sequential portion of the source data structure.

4. The data structure format conversion system as claimed in claim 3 in which the back end converter further generates position requests, and the converter executive enables the front end converter to generate position information in response to the position requests.

5. A data structure format conversion system comprising:

a plurality of front end converters for converting respective source data structures in respective source data formats to intermediate data structures, at least one of said front end converters converting to a first intermediate data structure, and at least another of said front end converters converting to a second intermediate data structure;

a domain converter for converting the first intermediate data structure to the second intermediate data structure, and for converting the second intermediate data structure to the first intermediate data structure;

a plurality of back end converters for converting the intermediate data structures to respective target data structures in respective target data formats, at least one of said back end converters converting from the first intermediate data structure and at least another of said back end converters converting from the second intermediate data structure; and

a converter executive for effecting a conversion from a specified one of the source data structures to a specified one of the target data structures, said converter executive including a converter selecting portion for selecting a front end converter converting from the specified one of the source data structures and selecting a back end converter converting to the specified one of the target data structures, an intermediary selection portion for determining whether the format provided by the selected front end converter corresponds to the format required by the selected back end converter, an intermediate data structure portion for establishing for data transfer the intermediate data structure having the format provided by the selected front end converter and required by the selected back end converter when the intermediary selection portion determines that the format provided by the selected front end converter is the same as the format required by the selected back end converter, and a domain activation portion for activating the domain converter as an intermediary between the selected front end converter and the selected back end converter when the intermediary selection portion determines that the format provided by the selected front end converter is not the same as the format required by the selected back end converter.

6. The data structure format conversion system as claimed in claim 5 in which the selected back end converter operates iteratively in connection with sequential portions of the source data structure, and the back end converter iteratively generates data requests which enable the converter executive to, in turn, enable the selected front end converter to perform a conversion operation in connection with a next sequential portion of the source data structure.

7. The data structure format conversion system as claimed in claim 5 in which the selected back end converter further generates position requests, and the converter executive enables the front end converter to generate position information in reponsive to the position requests.

8. The data structure format conversion system as claimed in claim 5 in which the first intermediate data structure is a document data structure, and the second intermediate data structure is a tabular data structure.

9. A method of operating a digital computer system for converting a source data structure in a specified source data format to a target data structure in a specified target data format;

said digital computer system having a plurality of front end converters for converting respective source data structures in respective source data formats to intermediate data structures, at least one of said front end converters converting to a first intermediate data structure, and at least another of said front end converters converting to a second intermediate data structure;

said digital computer system also having a domain converter for converting the first intermediate data structure to the second intermediate data structure, and for converting the second intermediate data structure to the first intermediate data structure;

said digital computer system also having a plurality of back end converters for converting the intermediate data structures to respective target data structures in respective target data formats, at least one of said back end converters converting from the first intermediate data structure and at least another of said back end converters converting from the second intermediate data structure;

said method comprising the steps of;

selecting a front end converter converting from the specified one of the source data structures and selecting a back end converter converting to the specified one of the target data structures;

determining whether the format provided by the selected front end converter corresponds to the format required by the selected back end converter;

establishing for data transfer the intermediate data structure having the format provided by the selected front end converter and required by the selected back end converter when the format provided by the selected front end converter is the same as the format required by the selected back end converter; and

acitivating the domain converter as an intermediary between the selected front end converter and the selected back end converter when the format provided by the selected front end converter is not the same as the format required by the selected back end converter.

10. The method of operating a digital computer system as claimed in claim 9, wherein the selected back end converter is operated iteratively in connection with sequential portions of the source data structure, the selected back end converter iteratively generates data requests, and the selected front end converter performs a conversion operation in connection with a next sequential portion of the source data structure in response to each of said data requests.

11. The method of operating a digital computer system as claimed in claim 10, wherein the back end converter further generates position requests, and wherein the method further comprises enabling the front end converter to generate position information in response to the position requests.

12. The method of operating the digital computer system as claimed in claim 9, wherein the first intermediate data structure is a document data structure, and the second intermediate data structure is a tubular data structure.