JP2009087285A - System, method and program for xml parsing, electronic device, and web service - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain an XML parsing function equivalent to a DOM by saving a memory and to load the XML parsing system to an incorporated system on which the DOM can not be loaded by resource restriction. <P>SOLUTION: The XML parsing system 60 includes: an element analysis part (SOAP parser 62) which analyzes construction of XML data (SOAP data SD) input from the outside to acquire a pointer of each element constituting the XML data (SOAP data SD); and a sequential information acquisition part (event drive parser 63) which sequentially acquires information about elements of the XML data pointed by the pointer for every pointer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an XML syntax analysis system, an XML syntax analysis method, an XML syntax analysis program, an electronic device, and a Web service for an embedded program.

  In recent years, with the spread of Web services and the like, communication using XML (eXtensible Markup Language) data has become mainstream as a communication means between clients and servers on a network. There are no exceptions regarding devices such as network-compatible printers and scanners, and communication in which a request from a client such as a PC is received as XML data and a response to the request is performed as XML data has become widespread.

  In addition, a protocol specification called SOAP (Simple Object Access Protocol) for exchanging messages and calling remote procedures on an XML basis for cooperation between Web services has been proposed. SOAP is a simple and lightweight protocol specification for exchanging information between applications (objects) on a network.

  The device needs to analyze and process the XML syntax constituting the SOAP data in order to confirm the content of the client request from the SOAP data sent from the client. There is a DOM (Document Object Model) as a mechanism for solving this, but the DOM requires a large program size and a RAM size from the system. Devices such as printers and scanners are limited in program size and RAM size (memory size that can be used when the device starts up), and therefore must be configured to operate with as little program size and memory as possible, so DOM cannot be applied. There are many cases.

  In order to solve this problem, for example, Patent Document 1 describes a method for realizing high speed by performing parsing processing and validity verification at the same time.

JP-A-2005-242912

  However, the conventional method has a problem that the program size can be reduced, but the RAM size remains large.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
The host application includes an upper application, an element analysis unit, and a sequential information acquisition unit. The upper application transmits an analysis instruction of XML data input from the outside to the element analysis unit, and the analysis instruction is sent from the element analysis unit. The element analysis unit receives the analysis instruction from the upper application, instructs the sequential information acquisition unit to perform analysis, and performs the upper application. The analysis instruction is repeated until the analysis result for the analysis instruction is obtained, and the sequential information acquisition unit receives the analysis instruction from the element analysis unit, analyzes the XML data, and converts the analysis result to the analysis result. An XML parsing system characterized by being transmitted to an element analysis unit.

  According to this configuration, since the XML parsing function equivalent to DOM can be realized with memory saving, the XML parsing function can be realized by installing in an embedded system where DOM cannot be installed due to resource limitation.

[Application Example 2]
In the XML syntax analysis system described above, the XML syntax analysis system generates hierarchical structure data in which a hierarchical structure of elements constituting the XML data is recorded based on the analysis result of the upper application, and the element analysis The unit determines whether the element transmitted to the sequential information acquisition unit is ahead of the element requested by the higher-order application based on the hierarchical structure data. An XML parsing system, characterized in that an instruction for processing from the beginning of the XML data is sent to an information acquisition unit.

  According to this configuration, since the positional relationship of the current element in the XML data can be grasped from the hierarchical structure data, conventionally, when there is a pointer in the middle part of the XML data, in order to reach the element above the XML, After moving the pointer to the end of the data, it was possible to save a great deal of time spent returning to the beginning.

[Application Example 3]
A host application process, an element analysis process, and a sequential information acquisition process. The host application process sends an analysis instruction of XML data input from the outside to the element analysis process, and the analysis from the element analysis process An analysis result for the instruction is received, a predetermined process is performed based on the analysis result, and the element analysis step receives the analysis instruction from the upper application step and instructs the sequential information acquisition step for analysis, and the upper application The analysis instruction is repeated until the analysis result with respect to the analysis instruction from the step is obtained, and the sequential information acquisition step receives the analysis instruction from the element analysis step, analyzes the XML data, and obtains the analysis result. An XML parsing method, wherein the XML parsing method is sent to the element analysis step.

[Application Example 4]
A host application step, an element analysis step, and a sequential information acquisition step. The host application step sends an analysis instruction of XML data input from the outside to the element analysis step, and the analysis from the element analysis step An analysis result for the instruction is received, a predetermined process is performed based on the analysis result, and the element analysis step receives the analysis instruction from the upper application step and instructs the sequential information acquisition step to perform analysis, and the upper application The analysis instruction is repeated until the analysis result for the analysis instruction from the step is obtained, and the sequential information acquisition step receives the analysis instruction from the element analysis step, analyzes the XML data, and obtains the analysis result. This is sent to the element analysis step. XML parsing program characterized.

  According to this configuration, since the XML parsing function equivalent to DOM can be realized with memory saving, the XML parsing function can be realized by installing in an embedded system where DOM cannot be installed due to resource limitation.

[Application Example 5]
An electronic apparatus comprising the XML parsing system described in Application Example 1 or 2 or the XML parsing program described in Application Example 4.

  According to this configuration, since the XML parsing function equivalent to DOM can be realized with memory saving, the XML parsing function can be realized by installing in an embedded system where DOM cannot be installed due to resource limitation.

[Application Example 6]
A web service comprising a plurality of the electronic devices described above.

[Application Example 7]
In the Web service described above, the Web service exchanges information by SOAP based on the XML data.

  According to this configuration, it is possible to create an application that does not depend on the environment by using SOAP that can be used by binding to various protocols.

  Hereinafter, an embodiment of an XML parsing system will be described with reference to the drawings.

(First embodiment)
<Configuration of XML parsing system>
First, the configuration of the XML parsing system according to the first embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing the configuration of the XML parsing system according to the first embodiment. As shown in FIG. 1, the XML parsing system 60 is incorporated in a network printer 100 as an example of an electronic device. The network printer 100 is connected to a client PC 200 via a network cable (LAN: Local Area Network) 300 to configure a printing system using a Web service.

  In the network printer 100, a CPU 20, a ROM 30, a RAM 40, and a print engine 50 are connected to the internal bus 10. The XML parsing system 60 is stored in the ROM 30 and loaded into the RAM 40 when the program is executed. The XML parsing system 60 includes a higher-level application 61, a SOAP parser 62 that is an element analysis unit, and an event-driven parser 63 that is a sequential information acquisition unit.

  The SOAP data SD describing the print request items from the client PC 200 is stored in the RAM 40 of the network printer 100 via the LAN 300. The upper application 61 analyzes the SOAP data SD stored in the RAM 40 using the SOAP parser 62 and sends a print command to the print engine 50. The host application 61 sends various APIs (Application Program Interface) for sending the analysis instruction of the SOAP data SD to the SOAP parser 62 and receiving the analysis result from the SOAP parser 62.

  The SOAP parser 62 receives an instruction to move from the higher-level application 61 to the child element or the elder brother element based on the API, and for the event-driven parser 63, analyzes the node that is the analysis unit of the event-driven parser 63 with the pointer PT. Instruct. The event driven parser 63 sequentially acquires the data EV for each node from the pointer position on the SOAP data SD stored in the RAM 40, and determines the type of the acquired node. Here, a node refers to a data string from “<“ to “>” or a data string from “>” to “<” as one node. For example, in FIG. 2, <soap: Header> and Message data are each one node, and a line feed and a blank are also treated as one node. The node type is the start node, the data enclosed in <> is the start node, the data enclosed in </> is the end node, and the others are values.

  The event driven parser 63 analyzes the SOAP data SD as described above, responds to the SOAP parser 62 with the analyzed node type, and moves the pointer PT to the end of the node. The SOAP parser 62 determines whether or not the pointer has moved to the child element or sibling element instructed by the upper application 61 based on the node type received from the event driven parser 63. In response to the completion of movement. When the upper application 61 receives the movement completion notification from the SOAP parser 62, the upper application 61 determines whether or not it has moved to the desired child element or sibling element, and if it has not moved, until it moves to the desired child element or sibling element, The movement instruction is repeated to the SOAP parser 62.

<Structure of SOAP data>
Next, the configuration of the SOAP data will be described with reference to FIG. FIG. 2 is a list showing an outline of the structure of the SOAP data.

  As shown in FIG. 2, the SOAP data SD is described in XML syntax. The SOAP data SD is composed of an envelope <soap: Envelope> on the first line, a header <soap: Header> on the second line, and a body <soap: Body> on the 17th line.

  The header <soap: Header> is a plurality of child elements <wsa: MessageID> on the third line, <wsa: Action> on the fourth line, <wsa: To> on the fifth line, <on the sixth line wsa: RelatesTo>, <wsa: ReplyTo> on line 7, <ext: AAA> on line 14, and <ext: BBB> on line 15. These multiple child elements are called sibling elements.

  <Wsa: ReplyTo> on the seventh line further includes <wsa: Address> on the eighth line and <wsa: ReferenceParameters> on the ninth line as child elements. In addition, <wsa: ReferenceParameters> on the 9th line further includes <ext: DDD> DDD data </ ext: DDD> on the 10th line as child elements, and <ext: EEE> EEE data </ ext: on the 11th line. EEE>, including.

  <Wsa: MessageID> on the third line contains the value Message data, <wsa: Action> on the fourth line contains the value Action data, and <wsa: To> on the fifth line says To data In the sixth line, <wsa: RelatesTo> includes a value “RelatesTo data”.

<Operation of XML parsing system>
Next, the operation of the XML parsing system will be described with reference to FIG. FIG. 3 is a flowchart showing the operation of the XML parsing system. It is assumed that the current pointer is located immediately before <soap: Header> on the second line of the SOAP data SD, and the upper application 61 wants to acquire the value Message data of <wsa: MessageID> on the third line.

  The upper application 61 instructs the SOAP parser 62 to move the analysis to the next child element in order to obtain a desired value of the SOAP data SD.

  When the SOAP parser 62 receives an analysis movement instruction to the child element from the upper application 61, it instructs the event drive parser 63 to proceed with the analysis of the SOAP data SD.

  First, in step S100, the event driving parser 63 acquires a pointer of the header <soap: Header> of the SOAP data SD.

  Next, in step S102, the event-driven parser 63 sequentially acquires the data EV from the SOAP data SD, recognizes that the data is a header by acquiring <soap: Header> on the second line as the data, In addition to notifying the SOAP parser 62 that the header has been acquired, the pointer PT is moved to the rear end of <soap: Header>.

  The SOAP parser 62 determines that the analysis has moved to the child element that has received an instruction from the upper application 61 and notifies the upper application 61 of the analysis result of the child element.

  When the upper application 61 receives the analysis result of the child element, it determines whether the received analysis result is the desired analysis result. If the upper application 61 determines that the analysis result is not the desired analysis result, the upper application 61 advances the analysis to the next child element. The parser 62 is instructed.

  When the SOAP parser 62 receives an analysis movement instruction to the child element from the upper application 61, it instructs the event drive parser 63 to proceed with the analysis of the SOAP data SD.

  The event-driven parser 63 acquires the pointer of the SOAP data SD, acquires the SOAP data SD from the pointer position, and acquires the line feed immediately after <soap: Header> and the space immediately before <wsa: MessageID>. Is determined to be a value and notifies the SOAP parser 62 that it is a value, and the pointer is moved after the space, that is, immediately before <wsa: MessageID.

  When the SOAP parser 62 receives from the event driving parser 63 that the analysis result is a value, the SOAP parser 62 inquires of the event driving parser 63 whether or not the analyzed value is blank.

  The event driven parser 63 responds to the SOAP parser 62 that the value is blank. If the SOAP parser 62 finds that the analysis result is blank, it can determine that the analysis has not reached the child element, so the event-driven parser 63 can proceed with the analysis without responding to the upper application 61. Give instructions.

  The above flow is repeated until an analysis result of a desired element is obtained.

  Next, in step S104, it is determined whether or not the current element has a child element. If there is a child element, the process proceeds to step S110, and if there is no child element, the process proceeds to step S106.

  Next, in step S106, it is determined whether or not there is a next element. If there is a next element, the process proceeds to step S108, and if there is no next element, the process ends.

  Next, in step S108, the value of the next element in the same hierarchy as the current element is acquired, and the process proceeds to step S104.

  On the other hand, in step S110, the value of the child element is acquired, and the process proceeds to step S104.

  According to the present embodiment described above, the following effects can be obtained.

  In the present embodiment, the SOAP parser 62 acquires the element pointer PT from the SOAP data SD stored in the RAM 40 based on the API, sequentially sends the element pointer PT to the event drive parser 63, and the event drive parser 63 sends the pointer PT. Since the information of the element pointed to is acquired and returned to the upper application 61, the XML parsing function equivalent to DOM can be realized with memory saving, so the XML parsing function can be implemented by installing it in an embedded system where DOM cannot be installed due to resource limitations. Can be implemented, and a web service can be installed.

(Second Embodiment)
In the first embodiment, the pointer could not be moved from the current position before starting the analysis, but in the second embodiment, node configuration management data that is hierarchical structure data of the SOAP data SD is created, and the node It is different from the first embodiment in that the pointer can be moved to the head based on the configuration management data. In particular, when the SOAP data SD size is large and the upper application 61 requests the analysis result of the node immediately before the current pointer, the analysis of the event-driven parser 63 can only proceed sequentially in one direction. It took a lot of time to obtain the analysis results.

  In the second embodiment, by creating node configuration data of the SOAP data SD and referring to the node configuration data, the positional relationship between the current pointer position and the desired node can be known. And the distance from the current pointer to the desired node are compared. If the distance from the head to the desired node is shorter, the pointer is moved to the head and the analysis time of the SOAP data SD is shortened. be able to.

  The operation of the XML syntax analysis system in the second embodiment will be described below. In the second embodiment, the pointer exists immediately before </ wsa: ReferenceParameters> on the 12th line in FIG. 2, and the upper application 61 moves to the child element of <wsa: ReferenceParameters> on the 9th line in FIG. Is required.

  FIG. 4 is a block diagram showing node configuration management data of SOAP data. First, when the SOAP data SD is received from the client PC 200, the SOAP data SD is stored in the RAM 40, and the node configuration management data 400 of the SOAP data SD as shown in FIG. 4 is created and analyzed by the event driven parser 63. It shall be updated each time.

  Here, FIG. 4 will be described. The current element 401 represents the element where the current pointer is located. The current position type 402 represents the type of node where the current pointer is located. The current hierarchy number 403 means the hierarchy of the element where the pointer is located. The parent element 404 to which the current element belongs represents all the parent elements to which the child element where the pointer is located belongs. A head element 405 of each hierarchy indicates a node that appears first in each hierarchy before reaching the element where the current pointer is located. The total number of analyzed elements 406 represents the total number of elements analyzed until the current pointer is reached.

  When the SOAP parser 62 receives a request to move to a child element of <wsa: ReferenceParameters> from the upper application 61, the SOAP parser 62 acquires the total number of elements 406 analyzed in the node configuration management data 400.

  Since the total number of elements 406 analyzed is 11, the SOAP parser 62 determines that the child elements of <wsa: ReferenceParameters> have already been analyzed, and initializes the event-driven parser 63.

  Since the pointer returns to the top of the SOAP data SD by the initialization of the event driven parser 63, the analysis is performed in the same manner as in the first embodiment until the child element of <wsa: ReferenceParameters> is reached.

  According to the present embodiment described above, the following effects can be obtained.

  In the second embodiment, since the current positional relationship of the pointers in the SOAP data SD can be grasped by the node configuration management data 400, conventionally, when there is a pointer in the middle of the SOAP data SD, it is necessary to reach the element above it. Can save a great deal of time spent because the pointer has moved back to the beginning after moving the pointer to the end of the SOAP data SD.

  As mentioned above, although the embodiment of the XML parsing system has been described, it is not limited to such an embodiment, and can be implemented in various forms without departing from the spirit of the system. Hereinafter, a modification will be described.

  (Modification 1) Modification 1 of the electronic apparatus will be described. In the first embodiment, the case of the network printer 100 as an electronic device has been described, but it can also be used for network devices such as a network scanner, a network projector, a fax machine, and a network storage.

The block diagram which shows the structure of the XML syntax analysis system which concerns on 1st Embodiment. The list which shows the outline of a structure of SOAP data. The flowchart which shows operation | movement of an XML parsing system. The block diagram which shows the node structure management data of SOAP data.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Internal bus, 20 ... CPU, 30 ... ROM, 40 ... RAM, 50 ... Print engine, 60 ... XML parsing system, 61 ... Upper level application, 62 ... SOAP parser, 63 ... Event drive parser, 100 ... Network printer, 200: Client PC, 300: LAN.

Claims (7)

A host application,
An element analysis unit;
A sequential information acquisition unit;
Including
The host application transmits an analysis instruction for XML data input from the outside to the element analysis unit, receives an analysis result for the analysis instruction from the element analysis unit, and performs predetermined processing based on the analysis result ,
The element analysis unit receives the analysis instruction from the upper application and instructs the sequential information acquisition unit to perform analysis, and repeats the analysis instruction until obtaining the analysis result for the analysis instruction from the upper application,
The sequential information acquisition unit receives the analysis instruction from the element analysis unit, analyzes the XML data, and transmits the analysis result to the element analysis unit.
An XML parsing system characterized by that. The XML parsing system according to claim 1,
The XML parsing system generates hierarchical structure data in which a hierarchical structure of elements constituting the XML data is recorded based on the analysis result of the upper application,
The element analysis unit determines whether the element transmitted to the sequential information acquisition unit is ahead of the element requested from the higher-order application based on the hierarchical structure data, and when determining that the element is ahead , To send an instruction to process from the beginning of the XML data to the sequential information acquisition unit,
An XML parsing system characterized by that. Upper application process,
Element analysis process;
Sequential information acquisition process;
Including
The upper application process sends an analysis instruction for XML data input from the outside to the element analysis process, receives an analysis result for the analysis instruction from the element analysis process, performs a predetermined process based on the analysis result,
The element analysis step receives the analysis instruction from the upper application step, instructs the sequential information acquisition step to analyze, and repeats the analysis instruction until obtaining the analysis result for the analysis instruction from the upper application step,
The sequential information acquisition step receives the analysis instruction from the element analysis step, analyzes the XML data, and sends the analysis result to the element analysis step.
An XML parsing method characterized by the above. Upper application steps;
An element analysis step;
Sequential information acquisition step;
Including
The upper application step sends an analysis instruction for XML data input from the outside to the element analysis step, receives an analysis result for the analysis instruction from the element analysis step, performs a predetermined process based on the analysis result,
The element analysis step receives the analysis instruction from the upper application step, instructs the sequential information acquisition step to analyze, and repeats the analysis instruction until obtaining the analysis result for the analysis instruction from the upper application step,
The sequential information acquisition step receives the analysis instruction from the element analysis step, analyzes the XML data, and sends the analysis result to the element analysis step.
An XML parsing program characterized by that.   An electronic apparatus comprising the XML parsing system according to claim 1 or 2 or the XML parsing program according to claim 4.   A Web service comprising a plurality of electronic devices according to claim 5.   7. The web service according to claim 6, wherein the web service exchanges information by SOAP based on the XML data.

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