Note: Descriptions are shown in the official language in which they were submitted.
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METHOD OF DELIVERING AN ELECTRONIC
DOCUMENT TO A REMOTE ELECTRONIC DEVICE
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to the delivery of electronic documents, and in
particular to a
method for delivering an electronic document having hyperlinks to a remote
electronic device.
Background Information
Mobile communication devices are becoming increasingly popular for business
and
personal use due to a relatively recent increase in number of services and
features that the
devices and mobile infrastructures support. Handheld mobile communication
devices,
sometimes referred to as mobile stations or handheld electronic devices, are
essentially portable
computers having wireless capability, and come in various forms. Numerous
types of mobile
communication devices are known. Examples of such mobile communication devices
include,
for instance, personal data assistants (PDAs), handheld computers, two-way
pagers, cellular
telephones, and the like. While their reduced size is an advantage to
portability, bandwidth and
processing constraints of such devices present challenges to the downloading
and viewing of
documents, such as word processing documents, tables and images.
Electronic documents are produced using various computer programs, such as
word
processors, spreadsheet programs, financial software, and presentation
software. In addition to
text, documents can contain navigational information such as hyperlinks and
bookmarks. As is
known in the art, and as used herein, a hyperlink refers to a graphic or piece
of text in a hypertext
document that allow you to "jump" to another section of the same document or
to another
document on a network such as the World Wide Web by activating (e.g., clicking
on) the
hyperlink. In addition, as is known in the art, and as used herein, a
bookmark, also known as an
anchor, refers to the destination of a particular hyperlink (i.e., the
location within the particular
document that was pointed to by the hyperlink).
When the user of a mobile communication device wishes to access an electronic
document which resides on a remote computer and view a certain part of the
document on the
mobile communication device, the entire electronic document is typically
transmitted over a
potentially bandwidth-constrained wireless network to the mobile communication
device. This
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often happens when a user of a mobile communication device wishes to open and
view an
attachment to an email message. In wireless communications systems,
attachments are typically
not automatically included with an email message due to bandwidth constraints,
but instead are
stored on the email server and must be requested in order to open and view
them. For example, 5
if a 400-page document is attached to an email, and a user wishes to view only
the one-page
terms and conditions section of the document that is pointed to by a hyperlink
provided in the
document (the terms and conditions are a bookmark), the entire document is
typically transmitted
to the mobile communication device, of which the user only views a small
portion on the mobile
communication device.
Once on the device, the electronic document is viewed using the mobile
communication device's user interface, which typically differs from the user
interface used to
create and view the document on a personal computer. For example, while the
user interface on a
personal computer used to create an electronic document may include a large,
color display and a
pointing device such as a mouse, the mobile communication device may have a
small, non-color
screen, and may not have a mouse. In addition, the mobile communication device
typically has
greater processing power and memory limitations than a personal computer used
to view the
electronic document, which may be very large in size. Thus, there is a need
for an improved
method for delivering electronic documents, particularly those containing
hyperlinks, to a
remotely located electronic device, such as a mobile communication device.
SUMMARY OF THE INVENTION
An improved method for delivering an electronic document having hyperlinks to
a
remote electronic device enables the retrieval of hyperlink target content
(bookmark) without
having to download the entire document content onto a mobile communication
device over a
potentially bandwidth-constrained wireless network. As a result, the usage
consumption of the
cpulmemory/power of mobile communication devices may be reduced, along with
the
minimization of overall network bandwidth usage.
These and other aspects of the invention are provided by a method of preparing
a
document for delivery from a server to a remote electronic device, comprising:
building a
graph structure representing a map of said document, said graph structure
having a plurality
of nodes, said nodes including one or more hyperlink nodes each having a
corresponding
hyperlink and one or more bookmark nodes each having a corresponding bookmark,
wherein
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the hyperlink of each of said one or more hyperlink nodes has as its
destination the bookmark
of one of said one or more bookmark nodes; traversing and paginating said
graph structure
into successive pages based on a page size limit, wherein each of said nodes
is included in
one of said successive pages and wherein each of said successive pages has a
corresponding
page index value; and for each of said nodes that is one of said hyperlink
nodes, storing in
association with the one of said hyperlink nodes during said traversing and
paginating a
bookmark page index value, said bookmark page index value being the page index
value of
the one of said successive pages that includes the one of said bookmark nodes
having the
bookmark that is the destination of the hyperlink of the one of said hyperlink
nodes, and
wherein said traversing and paginating and said storing comprise: determining,
for each
particular node of said plurality of nodes, whether the particular node is one
of said hyperlink
nodes or one of said bookmark nodes; if said particular node is one of said
hyperlink nodes,
determining whether a first name string of the particular node that is one of
said hyperlink
nodes is stored in a bookmark map, and if said first name string is stored in
said bookmark
map, retrieving an associated page index value that is associated with the
first name string
from said bookmark map and storing the associated page index value in
association with the
particular node that is one of said hyperlink nodes, and if said first name
string is not stored
in said bookmark map, storing the particular node that is one of said
hyperlink nodes in a
hyperlink map in association with said first name string; and if said
particular node is one of
said bookmark nodes, determining whether a second name string of the
particular node that is
one of said bookmark nodes is stored in said hyperlink map, and if said second
name string is
stored in said hyperlink map, retrieving an associated hyperlink node that is
associated with
the second name string from said hyperlink map and storing in association with
the
associated hyperlink node the page index value of the one of said successive
pages that
includes the particular node that is one of said bookmark nodes, and if said
second name
string is not stored in said hyperlink map, storing the page index value of
the one of said
successive pages that includes the particular node that is one of said
bookmark nodes in said
bookmark map in association with said second name string.
The invention also relates to method of delivering a document from a server to
a
remote electronic device comprising: building a graph structure representing a
map of said
document, said graph structure having a plurality of nodes, said nodes
including one or more
hyperlink nodes each having a corresponding hyperlink and one or more bookmark
nodes
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each having a corresponding bookmark, wherein the hyperlink of each of said
one or more
hyperlink nodes has as its destination the bookmark of one of said one or more
bookmark
nodes; traversing and paginating said graph structure into successive pages
based on a page
size limit, wherein each of said nodes is included in one of said successive
pages and wherein
each of said successive pages has a corresponding page index value; and for
each of said
nodes that is one of said hyperlink nodes, storing in association with the one
of said hyperlink
nodes during said traversing and paginating a bookmark page index value, said
bookmark
page index value being the page index value of the one of said successive
pages that includes
the one of said bookmark nodes having the bookmark that is the destination of
the hyperlink
of the one of said hyperlink nodes; transmitting a particular one of said
successive pages
from said server to said remote electronic device, said particular one of said
successive pages
containing the hyperlink of one or more of said hyperlink nodes; displaying
said particular
one of said successive pages on said remote electronic device; receiving an
information
request from said remote electronic device indicating that the hyperlink of a
particular one of
said one or more of said hyperlink nodes has been activated; identifying the
bookmark page
index value that is stored in association with the particular one of said one
or more of said
hyperlink nodes; transmitting a second one of said successive pages to said
remote electronic
device, wherein the second one of said successive pages corresponds to the
identified
bookmark page index value and; displaying said second one of said successive
pages on said
remote electronic device, and, wherein said traversing and paginating and said
storing
comprise: determining, for each particular node of said plurality of nodes,
whether the
particular node is one of said hyperlink nodes or one of said bookmark nodes;
if said
particular node is one of said hyperlink nodes, determining whether a first
name string of the
particular node that is one of said hyperlink nodes is stored in a bookmark
map, and if said
first name string is stored in said bookmark map, retrieving an associated
page index value
that is associated with the first name string from said bookmark map and
storing the
associated page index value in association with the particular node that is
one of said
hyperlink nodes, and if said first name string is not stored in said bookmark
map, storing the
particular node that is one of said hyperlink nodes in a hyperlink map in
association with said
first name string; and if said particular node is one of said bookmark nodes,
determining
whether a second name string of the particular node that is one of said
bookmark nodes is
stored in said hyperlink map, and if said second name string is stored in said
hyperlink map,
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retrieving an associated hyperlink node that is associated with the second
name string from
said hyperlink map and storing in association with the associated hyperlink
node the page
index value of the one of said successive pages that includes the particular
node that is one of
said bookmark nodes, and if said second name string is not stored in said
hyperlink map,
storing the page index value of the one of said successive pages that includes
the particular
node that is one of said bookmark nodes in said bookmark map in association
with said
second name string.
In either embodiment, the remote electronic device may be a mobile
conununication
device, such as a PDA or cell phone, or a non-mobile communication device,
such as a PC. In
addition, the server may be an email server and the document may an attachment
to an email. In
the preferred embodiment, the graph structure is a Document Object Model
(DOM). Moreover,
the graph structure may be built when the document is requested, or may have
been built
previously and stored (e.g., cached), and accessed when the document is
requested.
Additional aspects include:
A method of preparing a document for delivery from a server to a remote
electronic
device, comprising:
building a graph structure representing a map of said document,
said graph structure having a plurality of nodes, said nodes including one or
more
hyperlink nodes each having a corresponding hyperlink and one or more bookmark
nodes
each having a corresponding bookmark, wherein the hyperlink of each of said
one or more
hyperlink nodes has as its destination the bookmark of one of said one or more
bookmark
nodes;
traversing and paginating said graph structure into successive pages based on
a page
size limit, wherein each of said nodes is included in one of said successive
pages and wherein
each of said successive pages has a corresponding page index value; and
for each of said nodes that is one of said hyperlink nodes, storing in
association with the one
of said hyperlink nodes during said traversing and paginating a bookmark page
index value,
said bookmark page index value being the page index value of the one of said
successive
pages that includes the one of said bookmark nodes having the bookmark that is
the
destination of the hyperlink of the one of said hyperlink nodes.
A method of delivering a document from a server to a remote electronic device,
comprising:
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building a graph structure representing a map of said document, said graph
structure
having a plurality of nodes, said nodes including one or more hyperlink nodes
each having a
corresponding hyperlink and one or more bookmark nodes each having a
corresponding
bookmark, wherein the hyperlink of each of said one or more hyperlink nodes
has as its
destination the bookmark of one of said one or more bookmark nodes;
traversing and paginating said graph structure into successive pages based on
a page
size limit, wherein each of said nodes is included in one of said successive
pages and wherein
each of said successive pages has a corresponding page index value; and
for each of said nodes that is one of said hyperlink nodes, storing in
association with the one of said hyperlink nodes during said traversing and
paginating a
bookmark page index value, said bookmark page index value being the page index
value of
the one of said successive pages that includes the one of said bookmark nodes
having the
bookmark that is the destination of the hyperlink of the one of said hyperlink
nodes;
transmitting a particular one of said successive pages from said server to
said remote
electronic device, said particular one of said successive pages containing the
hyperlink of one
or more of said hyperlink nodes;
receiving an information request from said remote electronic device indicating
that
the hyperlink of a particular one of said one or more of said
hyperlink nodes has been activated;
identifying the bookmark page index value that is stored in association with
the
particular one of said one or more of said hyperlink nodes; and
transmitting a second one of said successive pages to said remote electronic
device,
wherein the second one of said successive pages corresponds to the identified
bookmark page
index value.
BRIEF DESCRIPTION OF THE DRAWINGS
A full understanding of the invention can be gained from the following
Description
of the Preferred Embodiments when read in conjunction with the accompanying
drawings in
which:
Figure 1 is a block diagram of a network environment in accordance with the
invention;
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Figure 2 is a tree diagram showing the basic structure of a Document Object
Model
(DOM) used in the preferred embodiment of the invention;
Figure 3 shows the top-level of the DOM structure in Figure 2;
Figure 4A is an exemplary word processing document, and Figure 4B shows a DOM
structure for the word processing document shown in Figure 4A;
Figure 5A is an exemplary table document, and Figure 5B shows a DOM structure
for the
table document shown in Figure 5A;
Figure 6A is an exemplary word processing document containing an image
subdocument,
and Figure 6B shows a DOM structure for the word processing document shown in
Figure 6A;
Figure 7 is a flowchart showing a first stage of a method of delivering an
electronic
document according to the invention;
Figures 8A and 8B are a flowchart showing a second stage of a method of
delivering an
electronic document according to the invention; and
Figure 9 is a flowchart showing a third stage of a method of delivering an
electronic
document according to the invention.
Similar numerals refer to similar parts throughout the specification.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to Figure 1, network environment 10 is shown in which the
invention may
be practiced. Network environment 10 includes a mobile communication device 12
communicating via a wireless network 14 to a server 16 for downloading
documents, such as
email attachments, stored on server 16 to the mobile communication device 12.
Sever 16 may
be, for example, an email server associated with the mobile communication
device 12. While
only one mobile communication device 12 and server 16 are shown for
illustration purposes, a
person of skill in the art will understand that network environment 10 could
have many such
mobile communication devices and servers for performing services such as,
without limitation,
email services, hosting web sites or graphic download sites, and providing
access to picture files
such as JPEG, TIFF, BMP, PNG, SGI, MP4,MOV, GIF, SVG. As would be understood
by one
of ordinary skill in the art, wireless network 14 may be a GSM/GPRS, CDPD,
TDMA, iDEN
Mobitex, or DataTAC network, or a future network such as EDGE or UMTS, or the
like.
Referred to throughout this document, for the purpose of describing the
preferred
embodiment of the invention, is the structure of a Document Object Model (DOM)
for a
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document, such as an email attachment, to be viewed on mobile communication
device 12. The
DOM for any document is a graph structure that represents a map of the
document. The server
16 uses a file-parsing distiller in the preferred embodiment, for a specific
document type, to build
the DOM structure representing an attachment (a particular document) of that
document type.
The document DOM structure is, once created, stored in a memory cache of
server 16, and can
be iterated bi-directionally. Although one particular graph structure is
described herein, other
graph structures may be used in connection with the invention.
As shown in Figure 2, the graph-based document DOM structure consists of nodes
and
leaves. The nodes serve as the parents of leaves and nodes, while leaves are
end points of a
branch in the graph. Each node and leaf can have a set of attributes to
specify its own
characteristics. For example, a paragraph node can contain attributes to
specify its alignment,
style, entry of document TOC, etc. In addition, each of the nodes and the
leaves has a unique
identifier, called a DOM ID, to identify itself in the document DOM structure.
The document DOM structure is divided into three parts: top-level, component
and
references. The top level refers to the document root structure, while the
main document is
constructed in the component and the references represent document references
to either internal
or external sub-document parts. The following paragraphs examine each part in
detail.
The root node of a document DOM structure, referred to as "Document", contains
several
children nodes, referred to as "Contents", which represent different aspects
of the document
contents. Each "Contents" node contains one or multiple "Container" nodes used
to store
various document global attributes. The children of the "Container" nodes are
components,
which store the document structural and navigational information. When the
server 16 builds the
DOM structure for an attachment file for the first time, the top-level
structure is a single parent-
child chain as shown in Figure 3:
Three types of components are defined by the server 16: text components, table
components and image components, which represent text, tables and images in a
document,
respectively. The text and table components are described in detail below, and
the image
component structure is identical.
A component consists of a hierarchy of command nodes. Each command represents
a
physical entity, a property, or a reference defined in a document. For the
text component, the
physical entity commands are page, section, paragraph, text segments,
comments, footnote and
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endnote commands, which by name define the corresponding entity contained in a
document.
The property commands for the text component are font, text color, text
background color,
hyperlink start/end and bookmark commands. The text component has only one
reference
command, referred to as the text reference command, which is used to reference
a subdocument
defined in the main body of a document. Usually, the children of a text
component are page or
section command nodes that, in turn, comprise a set of paragraph command
nodes. The
paragraph command can contain one or multiple nodes for the remaining command
types.
Figure 4A shows a sample text document, and Figure 4B shows the corresponding
document DOM structure. As Figure 4B demonstrates, the section command, which
is the child
of the text component, consists of two paragraph commands. The first paragraph
command
contains one text segment command and the text content for that paragraph is
added as an
attribute to the text segment command. The second paragraph command has a
relatively more
complex structure, as the text properties in the paragraph are much richer.
Each time a text
property (font, text color, etc) changes, a corresponding text property
command is created and
the change value is added to that command as an attribute. The subsequent text
segment
command records the text with the same text property as an attribute. As
document structure
gets richer and more complex, more commands of corresponding types are created
and the
document properties are added as attributes to those commands.
The table component has the same three types of commands as the text
component, but
different command names. Figure 5A shows a sample table document, and the
corresponding
document DOM structure for the sample table document is shown in Figure 5B. As
shown in
Figure 5B, the table component has physical entity type commands of table,
tablerow and
tablecell, where the tablecell command can contain all available commands for
the text
component. In the example shown, the first child TableRow command of the table
command has
an attribute "Index" defined by value of 0. This indicates that the indicated
table row is the first
one defined in the table. The attribute of the leftmost tablecell command in
Figure 5B has the
same meaning.
A document sometimes contains subdocuments, for example images, tables, text
boxes,
etc. The DOM structure set forth herein uses a reference command to point to
the graph of such
subdocuments. Thus, for the following sample document shown in Figure 6A, the
server 16
generates the DOM structure shown in Figure 6B. The structure shown in Figure
6B is identical
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to that discussed above in connection with Figures 4B and 5B, except for the
attributes of the two
reference commands. The server 16 constructs the image in "Sample Three" as a
separate image
component, which contains all of the image data in its own DOM hierarchy. In
the DOM
structure for the main document, the values of the "Ref' attributes of those
two reference
commands point to the image component, as indicated by the dashed lines, such
that the DOM
structure connects together all parts of the document.
Having described the document DOM structure used to implement an embodiment of
the
invention, a detailed discussion will now be provided of a method of
delivering, upon request,
documents that contain hyperlinks from server 16 to mobile communication
device 12 according
to the invention. The method is a client and server side solution. The client
is the mobile device
attachment viewing application provided on mobile communication device 12 and
the server is
the document (attachment) handling process on server 16. This solution
contains three (3)
operational stages: (1) document DOM construction (Figure 7), (2) hyperlink
info
processing/delivery (Figures 8A and 8B), and hyperlink target contents
delivery (Figure 9). The
following sections describe each stage in detail.
Figure 7 is a flowchart showing the steps of stage 1. It will be noted that,
in performing
the steps shown in Figure 7, the server 16 uses a map in memory for document
DOM cache
storage wherein the key to the map is the document ID. Since the key to the
memory map is the
document ID, the algorithm used to calculate the document ID must guarantee
the uniqueness of
the key. According to the preferred embodiment, as set forth below, the
algorithm used inside
the server 16 to calculate the document ID is the MD5 messaging encryption
algorithm invented
by Professor Ronald L. Rivest of MIT Laboratory for Computer Science and RSA
Data Security,
Inc. There are several other hashing options that can be used. However, MD5 is
the most
efficient and reliable one based on the broad range of different document
contents required to be
processed by the server 16.
Referring to Figure 7, initially, the user of mobile communication device 12
sends a
request to the server 16 to view a document, such as an email attachment, and,
at step 100, that
request is received by server 16. The request sent by mobile communication
device 12 includes
the following information: (1) two attributes, and (2) a number of bytes
mobile communication
device 12 requires (referred to herein as the variable RequireSize) as a
response from the server
16 (e.g. 3K bytes). The two attributes are whether the mobile communication
device 12 is a
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color or monochrome device, and the screen size (width x height x color depth)
of the mobile
communication device 12 in pixels. Other information about the mobile
communication device
12 can also be transmitted to the server 16 (e.g. memory size). Next, at step
105, the server 16
constructs a document ID based on the document contents. Preferably, to
construct the
document ID, the original document file is opened and read in binary mode. The
server 16
creates an MD5 context structure, hashes the MD5 context structure with raw
binary data byte-
by-byte from the file, and finalizes the MD5 context structure and retrieves
the 16 byte key for
the file. The MD5 context structure has the following structure in syntax of
C++ language:
typedef struct
f
unsigned long adwState[4]; /* state (ABCD)
unsigned long adwCount[21; /* number of bits, modulo 2^64 (lsb first)
unsigned char abyBuffer[64]; /* input buffer */
} tMD5_CTX,=
Next, at step 110, the server 16 uses the document ID to check the document
DOM cache
to determine whether the document DOM structure for the requested document has
been
previously constructed. If the document DOM structure does exist in the cache,
then, at step 115,
the document DOM structure is retrieved from cache and the method proceeds to
stage 2 shown
in Figures 8A and 8B. If, however, the document DOM structure does not exist
in the cache,
then, at step 120, the server 16 builds the DOM structure for the document as
described
elsewhere herein. Next, at step 125, the server 16 adds the DOM structure just
built to the cache,
and the method proceeds to stage 2 shown in Figures 8A and 8B.
Caching the document DOM structure requires considerable memory, and therefore
increases the overall hardware deployment cost. On the other hand, building
the DOM structure
for a document is even more time and CPU intensive in contrast to the document
key
construction operation, especially for big documents. Since processing time is
more critical than
hardware deployment cost for wireless operation, caching the document DOM is
the approach
adopted for the preferred embodiment, rather than building the DOM structure
for the document
each time the server 16 receives a viewing request and then discarding the
structure after sending
the response back to the mobile communication device 12. It will be
appreciated, however, that
this latter method (creating the DOM structure each time and discarding it)
may be employed
without departing from the scope of the invention.
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Figures 8A and 8B are a flowchart showing the steps of stage 2 described
above. The
following terms and variables are mentioned in Figures 8A and 8B:
Pagelndex is a variable defined in the server 16 and used by the server 16 to
record the
current page index (number) being paginated by the server 16. The page index
is initially set to
0 indicating "Page 1."
PageSize is a variable defined in the server 16 and used by the server 16 to
record the
current size for the page being paginated and is reset to 0 when paginating a
new page.
Hyperlink map is a variable defined in the server 16 which is a container
consisting of the
element type of hyperlink node in the document DOM structure. The key (ID) for
each element
(each hyperlink node) in the hyperlink map is the corresponding name string
for the hyperlink,
which is the name of the destination of the hyperlink in question (a
bookmark). Initially, the
hyperlink map is empty.
Bookmark map is a variable defined in the server 16 which is a container
consisting of
the element type of current page index (Pagelndex value) for the bookmark in
the document
DOM structure. The key (ID) for each element (each bookmark node) in the
container is the
corresponding name string for the bookmark, which is the name identifying the
bookmark (the
destination of the associated hyperlink). Initially, the bookmark map is
empty.
In stage 2, as shown in Figures 8A and 8B, the server 16 traverses through the
DOM
structure of the document and breaks the DOM structure up into a number of
discrete blocks of
information, each one being referred to as a page, each block having a size
equal to the
RequireSize specified by the mobile communication device 12. By doing so,
server 16 paginates
the DOM structure according to the specified size and assigns each block of
information (i.e.,
each node within the block) a Pagelndex value. In addition, while doing so,
server 16 also adds
as an attribute to each hyperlink node the Pagelndex value associated with the
bookmark that
corresponds to the hyperlink node (i.e., the bookmark that is the destination
of the hyperlink).
As a result, each hyperlink node forming a part of a document DOM structure
will have
information enabling the page or block of information containing its
corresponding bookmark to
be readily identified.
Referring to Figures 8A and 8B, the method begins at step 130, where server 16
obtains
the first element (node) in the DOM structure of the requested document and
calculates the
output size of that node. Also, the PageIndex value (zero) is saved as an
attribute to the first
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node so that the first node can later be identified as the first node of that
block/page (the first
page). Next, at step 135, a determination is made as to whether the PageSize
variable (initially
set to zero) plus the calculated output size of the node is greater than the
specified RequireSize.
If the answer is no, which will be the case for the first node, then at step
140, the PageSize
variable is set equal to the current PageSize value plus the output size of
the node. If the answer
at step 135 is yes, meaning that the node in question, if added to the current
page, would cause
the current page to exceed the RequireSize (and thus that a new page should be
started), then, at
step 145, the Pagelndex variable is incremented by one (new page started).
Also, the new
PageIndex value is saved as an attribute to the current node so that it may
later be identified as
the first node (i.e., the staring point) of that particular block/page. Then,
at step 150, the
PageSize value is set equal to the output size of the current node.
Following step 140 or step 150, whichever the case may be, a determination is
made, at
step 155, as to whether the current node is a hyperlink node. If the answer is
yes, then, at step
160, a determination is made as to whether the name string for the hyperlink
in the node is in the
bookmark map (i.e., has that name string been added to the bookmark map as of
that point,
meaning that the corresponding bookmark has been processed). If the answer at
step 160 is yes,
then, at step 165, server 16 retrieves the Pagelndex value stored in the
bookmark map in
association with the name string and adds that Pagelndex value as an attribute
to the current
hyperlink node. If, however, the answer at step 160 is no, then, at step 170,
the current hyperlink
node is added to the hyperlink map with the corresponding name string as the
key for that
element.
Referring again to step 155, if the answer at that step is no (node is not a
hyperlink node),
then, at step 175, a determination is made as to whether the current node is a
bookmark node. If
the answer at step 175 is yes, then, at step 180, a determination is made as
to whether the name
string for the bookmark in the bookmark node is in the hyperlink map. If the
answer at step 180
is yes, then, at step 185, the hyperlink node from the hyperlink map that is
associated with the
name string is retrieved and the current Pagelndex is added as an attribute to
the retrieved
hyperlink node. If, however, the answer at step 180 is no, then, at step 190,
the current
Pagelndex is added to the bookmark map with the name string for the current
bookmark being
the key for that element.
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Referring again to step 175, if the answer at that step is no (which means
that the current
node is neither a hyperlink node nor a bookmark node), or following any of
steps 165, 170, 185
or 190, as the case may be, then, at step 195, a determination is made as to
whether there are
more element (nodes) left to process in the DOM structure. If the answer is
yes, then, at step
200, the next element (node) in the DOM structure is obtained and the method
proceeds to step
135. If, however, the answer at step 195 is no (meaning the entire DOM
structure has been
traversed), then, at step 205, an output consisting of the first block of
information (i.e., the first
page) is constructed and sent to the mobile communication device 12.
Specifically, all nodes
beginning with the node having an attribute of Pagelndex equal to zero and up
to, but not
including, the node having an attribute of Pagelndex equal to one are gathered
and included in
the output.
As will be appreciated, the method illustrated in Figures 8A and 8B will
result in the
pagination (i.e., division into blocks of information), according to a
specified size (RequireSize),
of the document requested by mobile communication device 12. In addition, at
the end of the
method illustrated in Figures 8A and 8B, each hyperlink node in the document
DOM structure
will have as an attribute the Pagelndex of the bookmark that corresponds to
the hyperlink of the
hyperlink node. Using that attribute, the page containing the bookmark
corresponding to any
particular hyperlink can be readily identified and obtained.
Figure 9 is a flowchart showing the steps of stage 3 of the processing
according to the
invention. As described above, at the end of stage 2 (Figures 8A and 8B), the
mobile
communication device 12 will have received an output from the server 16
consisting of the first
block of information (nodes with Pagelndex equal to 0, i.e., the first page)
from the requested
document. At step 210 shown in Figure 9, a determination is made as to whether
an information
request is subsequently received from the mobile communication device 12.
According to the
invention, the information request will be the result of the user of mobile
communication device
12 desiring to receive and view more of the requested document than is
currently resident on
mobile communication device 12. Such a request will preferably either be a
request for the next
sequential page (block of information) from the document, or a request for the
bookmark
(destination) associated with a hyperlink contained in the document
information that has already
been provided to the mobile communication device 12. Thus, if the answer at
step 210 is no, the
method returns to step 210 to await such a request. However, if the answer at
step 210 is yes,
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then, at step 215, a determination is made as to whether the request is a
request for the next
sequential page (block of information) from the document. If the answer at
step 215 is yes, then,
at step 220, an output is constructed using all of the nodes included in the
page that has a
Pagelndex value equal to the next sequential Pagelndex beyond the one
currently being viewed
on the mobile communication device 12. In particular, all nodes beginning with
the node having
an attribute of Pagelndex equal to the next sequential Pagelndex and up to,
but not including, the
node having an attribute of Pagelndex equal to one plus next sequential
Pagelndex are gathered
and included in the output. If, however, the answer at step 215 is no, meaning
that the request is
a request for the bookmark (destination) associated with a hyperlink
(resulting from, for
example, "clicking" on the hyperlink), then, at step 225, the Pagelndex value
contained in the
attributes of the corresponding hyperlink node is obtained. At step 230, an
output is constructed
from all of nodes that are included in the particular page that has a
Pagelndex value equal to the
one obtained in step 225. Specifically, all nodes beginning with the node
having an attribute of
PageIndex equal to the one obtained in step 225 and up to, but not including,
the node having an
attribute of Pagelndex equal to one plus the Pagelndex value obtained in step
225 are gathered
and included in the output. Following either step 230 or step 220, whichever
the case may be,
the method proceeds to step 235, where the constructed output is sent to the
mobile
communication device 12. The method then returns to step 210 to await another
information
request.
By using the three stage approach of processing hyperlinks on the server and
using the
PageIndex as the content identifier, the client on the mobile communication
device 12 will be
able to retrieve the hyperlink target content (bookmark) without having to
download the entire
document content onto the mobile communication device 12 over a potentially
bandwidth-
constrained wireless network. As a result, this approach reduces the usage
consumption of the
cpu/memory/power of mobile communication device 12. More importantly, this
approach will
also minimize the overall network bandwidth usage. This approach does,
however, require a
more intensive server-side operation than that of the prior art. For example,
the server 16 will
have to traverse the DOM structure of a document each time a mobile
communication device 12
sends a view request.
While specific embodiments of the invention have been described in detail, it
will be
appreciated by those skilled in the art that various modifications and
alternatives to those details
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could be developed in light of the overall teachings of the disclosure. For
example, while the
invention has been described in connection with the delivery of electronic
documents to a mobile
communication device, it will be appreciated that the invention may also be
utilized in
connection with the delivery of electronic documents to a non-mobile
electronic device such as a
personal computer or the like. Accordingly, the particular arrangements
disclosed are meant to
be illustrative only and not limiting as to the scope of the invention which
is to be given the full
breadth of the claims appended and any and all equivalents thereof.
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