Patent Publication Number: US-7596557-B2

Title: System and method for filtering XML files

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is related to a system and method for filtering XML files. 
     2. Description of Related Art 
     Extensible markup language (XML) is a standard for structuring information, the XML enables information to be easily distributed. XML files consist of nested elements, and each of the elements may contain content. The element or nested elements contains a start tag, a close tag and content in between them. 
     Given the widespread use of XML in both private and business environments, there is a growing need or desire for the ability to query the XML data quickly and accurately. XQuery is a query language that is designed to process data from XML files or any data source that can be viewed as XML/HTML . . . etc. Facing large numbers of query tasks (a query task is regarded as a task request), there is a need to process the task requests simultaneously. 
     Therefore, what is needed is a system and method for filtering XML files which can filter one or more XML files simultaneously. 
     SUMMARY OF THE INVENTION 
     A system for filtering XML files is provided in accordance with a preferred embodiment. The system includes a task control computer, a scheduling server, a processing server and a database. The database stores XQuery scripts of each of the tasks. The task control computer includes a task setting module and a scheduling module. The scheduling server includes a sending module. The processing server includes a script invoking module, a file filtering module and a merging module. The task setting module is configured for configuring the XQuery scripts of each of the tasks and a scheduled time to perform each of the tasks, and storing the XQuery scripts in the database. The scheduling module is configured for scheduling the tasks in the scheduling server. The sending module is configured for sending a task request to the processing server when it is time to perform the task. The script invoking module is configured for invoking the XQuery scripts of each of the tasks from the database when the task request is received. The file filtering module is configured for processing each of the XML files, and obtaining an XQuery result. The merging module is configured for merging the XQuery result of the XQuery scripts of each of the tasks, and storing a merged result of each of the tasks in the database. 
     A computer-based method for filtering XML files is also provided. The method includes the steps of: configuring XQuery scripts of each of the tasks and a scheduled time to perform each of the tasks, and storing the XQuery scripts in a database; scheduling the tasks in a scheduling server; sending a task request by the scheduling server to a processing server when it is time to perform the task; invoking the XQuery scripts of each of the tasks from the database when the processing server receives the task request; processing each of the XML files, and obtaining an XQuery result; merging the XQuery result of the XQuery scripts of each of the tasks, and storing a merged result of each of the tasks in the database. 
     Other systems, methods, features, and advantages of the present invention will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of hardware configuration of a system for filtering XML files in accordance with a preferred embodiment; 
         FIG. 2  is a schematic diagram showing function modules of the system of  FIG.1 ; and 
         FIG. 3  is a flowchart of a preferred method for filtering XML files in accordance with one embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a schematic diagram of hardware configuration of a system for filtering XML files (hereinafter, “the system”) in accordance with a preferred embodiment. The system typically includes a task control computer  10 , a scheduling server  20 , a processing server  30 , and a database  40 . The processing server  30  connects to a network  50  so that large numbers of XML files (i.e., XML-formatted web pages) can be retrieved. The task control computer  10  and the processing server  30  both connect to the database  40 . The database  40  is configured for storing XQuery scripts of each of the tasks and element contents of the XML files. An element contains a start tag, an end tag, and contents in between them. For example, the element “&lt;title&gt; this web page &lt;/title&gt;” has the start tag “&lt;title&gt;”, the end tag “&lt;/title&gt;”, and the element contents “this web page” between the start tag and the end tag. For simplicity purposes, an element name is derived from the start tag, such “title” or “&lt;title&gt;” as used in the example above. Each of the XQuery scripts may contain the element names of the elements in the XML files that need to be processed (retrieved). Each of the XML files may include one or more elements. In the preferred embodiment, each of the tasks filters the elements in one or more XML files. When the processing server  30  filters the XML files, only the elements with the element name included in the XQuery scripts are processed. 
     The task control computer  10  connects to the scheduling server  20 , and is configured for configuring the XQuery scripts of each of the tasks (i.e., configuring which element names of the elements in the XML files need to be processed), configuring a scheduled time to perform each of the tasks, storing the XQuery scripts in the database  40 , and scheduling the tasks in the scheduling server  20 . The scheduled time of the task is the time when the task is performed. Each of the tasks may include one or more XML files to be filtered. If the scheduled time of one or more of the tasks is the same, the processing server  30  filters the XML files of the one or more of the tasks simultaneously. Otherwise, the processing server  30  processes the tasks sequentially according to the scheduled time. The scheduling server  20  is configured for sending a task request to the processing server  30  when it is time to perform the task. 
     The processing server  30  also connects to the scheduling server  20 , and is configured for invoking the XQuery scripts of each of the tasks from the database  40  when the task request is received, filtering each of the XML files (i.e., retrieving the contents of the elements from each of the XML files in the network  50  according to the element names included in the XQuery script), obtaining an XQuery result (i.e., the contents of the elements), merging the XQuery result of the XQuery scripts of each of the tasks, and storing a merged result of each of the tasks in the database  40 . 
       FIG. 2  is a schematic diagram showing function modules of the system of  FIG.1 . The task control computer  10  may include a task setting module  110  and a scheduling module  111 . The scheduling server  20  may include a sending module  210 . The processing server  30  may include a script invoking module  310 , a file filtering module  311 , and a merging module  312 . 
     The task setting module  110  is configured for configuring the XQuery scripts of each of the tasks and a scheduled time to perform each of the tasks, and further for storing the XQuery scripts in the database  40 . Each of the tasks may include one or more XQuery scripts. Each of the XQuery scripts may contain the element names of the elements in the XML files that need to be processed (retrieved), and each of the XML files may include one or more elements. The scheduling module  111  is configured for scheduling the tasks in the scheduling server  20 . 
     The sending module  210  is configured for sending the task request to the processing server  30  when it is time to perform the task. The script invoking module  310  is configured for invoking the XQuery scripts of each of the tasks from the database  40  when the task request is received. 
     The file filtering module  311  is configured for filtering each of the XML files (i.e., retrieving the contents of the elements from each of the XML files in the network  50  according to the element names included in the XQuery script), and obtaining the XQuery result (i.e., the contents of the elements). 
     The merging module  312  is configured for merging the XQuery result of the XQuery scripts of each of the tasks, and storing the merged result of each of the tasks in the database  40 . For example, a task A includes two XQuery scripts: a1.xq and a2.xq; and a task B also includes two XQuery scripts: b1.xq and b2.xq. When the XQuery scripts of a1.xq, a2.xq, b1.xq, and b2.xq are invoked by the file filtering module  311 , the merging module  312  merges the XQuery result of each of the XQuery scripts of a1.xq and a2.xq to obtain the merged result of the task A, and merges the XQuery result of each of the XQuery scripts of b1.xq and b2.xq to obtain the merged result of the task B. Then, the merging module  312  stores the merged results of the task A and the merged results of the task B in the database  40 . 
     The file filtering module  311  also determines whether the network  50  is disconnected when filtering the XML files. If the network  50  is disconnected, the file filtering module  311  re-filters the XML files. 
       FIG. 3  is a flowchart of a preferred method for filtering XML files in accordance with one embodiment. In step S 401 , the task setting module  110  configures the XQuery scripts of each of the tasks and the scheduled time to perform each of the tasks, and stores the XQuery scripts in the database  40 . Each of the tasks may include one or more XQuery scripts. Each of the XQuery scripts may contain the element names of the elements in the XML files that need to be processed (retrieved), and each of the XML files may include one or more elements. 
     In step S 402 , the scheduling module  111  schedules the tasks in the scheduling server  20 . 
     In step S 403 , the sending module  210  sends the task request to the processing server  30  when it is time to perform the task. 
     In step S 404 , when the processing server  30  receives the task request, the script invoking module  310  invokes the XQuery scripts of each of the tasks from the database  40 . 
     In step S 405 , the file filtering module  311  filters each of the XML files (i.e., retrieving the contents of the elements from each of the XML files in the network  50  according to the element names included in the XQuery script), and obtains the XQuery result (i.e., the contents of the elements). 
     In step S 406 , the merging module  312  merges the XQuery result of each of the XQuery scripts of each of the tasks, and stores the merged result of each of the tasks in the database  40 . 
     The file filtering module  311  determines whether the network  50  is disconnected when filtering the XML files. If the network  50  is disconnected, the file filtering module  311  re-filters the XML files. 
     It should be emphasized that the above-described embodiments of the present invention, particularly, any “preferred” embodiments, are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiment(s) of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.