User Guide

of

Leaflet™

Introduction

Developing XML-enabled application requires XML transformation with some degree. The simplest translating happens while an Entity is resolved during the parsing of the XML document, in which the Entity is replaced by a string as defined early in the document. However, most application requires more transformation functionalities than Entity resolving alone.

Leaflet is a macro language translator, which is designed to help developer with XML transformation. It provides a simple and intuitive, yet powerful, way to do transformation.

Leaflet has two [mode]. In the first [mode], a transformation rule, called Shells and XML data are defined in the same document. The transformation will start in the Main Shell and result will be generated according all of the Shells and the XML data.

In the batch [mode], Shells are defined in advance and a translator with the Shells is created. The same set of Shells will be reused, instead of loading from disk and parsing every time. Result will be generated differently according to the XML data feed in. It works especially efficient in environment like Java Servlet. User data, likes cookies in user’s browser, user profile that is stored in the server and transaction result from database can be feed into the translator as XML Data. The resulting page will be generated differently to the transaction result and user’s preferences.

Also, with Slot and Selector, Shell architecture provides abstraction of to the rules. It functionalities are not available in any other XML solution in the market.

Beside abstraction, Leaflet also provides a rich set of functionalities, yet as intuitive, for Data extracting, Output encoding and Pattern matching (reg exp).

Despite Leaflet is rich in functionalities, its footprint is extremely small. The uncompressed jar file of the fully functional Leaflet is less than 100kB (the typical size of a jpeg photo you can find in the web). And, functions can be easily added to it extremely extensible architecture.

Content at a Glance

1/ Getting Started

Introduction

An Introductory Example

Example List of this book

Understands Leaflet Architecture

Understanding Tree structure

Passing Tree around

Understand DataSource

Defining a Shell

Translator and batch mode

2/ Using Leaflet

Marco definition/abstraction

Shell/Slot/Choice/Pipe

DataSource

BasicDataSource

FileDataSource

TempFileDataSource (create a temp file on behalf of servlet)

XMLFileDataSource

JDBCDataSource

Data selection

Identifing a branch or a set of branch -- XdataPath

ForEach/Exist/Switch

Eval

Output encoding

HttpString

Replace Character

Pattern matching/reg expression

Match/Split

Output Method

State (returned by translate)

ResultHandler (SAX-like interface)

TreeBuilder

3/ Advanced features

Defining your own predcate

adding new predecate into translator

Dynamic Data source

creating custom data source

CoureInfo example

Working with Servlet thin layer

need JavaScript which sent in XML data, instead of just key and

Forward compatibility

Define alternative for older translator

Using Leaflet in Multithread environment

Table of Content

1/ Getting Started

Introduction

An Introductory Example

Example List of this book

Understands Leaflet Architecture

Understanding Tree structure

Passing Tree around

Defining a Shell

Translator and batch mode

2/ Using Leaflet

Marco definition/abstraction

Shell/Slot/Selector

Data extraction

Identifing a branch or a set of branch -- XdataPath

ForEach/Exist/Switch

Eval

Output encoding

HttpString

Replace Character

Pattern matching/reg expression

Match/Split

Output Method

State (returned by translate)

ResultHandler (SAX-like interface)

TreeBuilder

3/ Advanced features

Defining your own predcate

adding new predecate into translator

Dynamic Data model

creating custom data model

CoureInfo example

Working with Servlet thin layer

need JavaScript which sent in XML data, instead of just key and

Forward compatibility

Define alternative for older translator

Using Leaflet in Multithread environment

4/ Appendixes

FAQ

Ok, transformation of XML, why not XSLT

Table of Examples

Introductory Example

Abstraction -- Company Title Bar

Abstraction– Advanced use – Uvic timetable

Swtich – Name Card vs. Table – that’s why you need switch and need it a lot

Extract Data -- Display name card

Extract Data – Advanced use -- CourseInfo Example

Split and Match – Unix User File, Mulitple IP Address

Output Encoding – SQL statement

Voting Searching site – get user’s link information in XML (maybe from java)

Calendar

User customize portral page

Part 1

Chapter 1

Part 1 -- Using Leaflet

-1/ Working with XML, a link to other tutorial

0/ Introducting example of how to use

The most common use of Leaflet is use it as preprocessor for HTML.

Class ABC {

public void main( String[] argv ) {

FileReader f = new FileReader( "example1.xml" );

Tree t = Tree.createTree( f );

Translator t = new Translator();

translateToXml( System.out );

}

In "example1.xml"

something

Output:

something

1/ Understanding and Working with Tree structure

Why not DOM?

for cross platform cumbersome to work in java

code is very ugly

Data/Rule

Identifiy a branch (support XPath later)

2/ Certaining Shell

Design yoru own tag.

New tag is often some old features plus something new.

More than Text representation

filling complicated form

Two way to present data on the web.

1/ iterate data into form

2/ rule for make tag, java object etc.

How this document organize

Need it?

Leaflet support the following type of operations

Shell and slot concept (like parameter)

1/ don't use slot (two way to abstractize)

<p>News: Nov 19, 1999 -- Vancouver ....</p>

2/ use slot

</Content>

3/ selector, shell, and slot

</Department>

</Content>

</CompanyPage>

3/ Working with data

Branch and Bough

ForEach

different style, different color for second line.

set limit

Exist

Swtich

Swtich – Name Card vs. Table – that’s why you need switch and need it a lot

<Name><First>Thomas</First><Middle>Tat-Man</Middle><Last>Yip</Last></Name>

<Email><Primary>tyip@leafosft</Primary></Email>

</NameCard>

<Param name=”FirstName”>Thomas</Param>

</Record>

SortList

DelimitorList

Overall example:

University schedule

4/ Output predecate

HttpString, Replace character

5/ External predecate (eval)

6/ Create Transtor

Cerating translator

adding shell into translator

Understand ResultInfo

Note: Thread safe

Setting ResultHandler

Start translating (into ResultHolder)

Result in Tree structure

7/ option of Handling the result

sax-style result handler

creating Java GUI widget

Using Reflection to create

Displaying tag to browser

special handling of <br>&lthr&gt etc

8/ Some possible use of Translator

[list whetever in my idea book]

Part 2 -- Advanced topic

9/ Defining your own predcate

In javascript

In Java

adding new predecate into translator

10/ Dynamic Data model

creating custom data model

CoureInfo example

11/ Working with servlet thin layer

need javascript which sent in xml data, instead of just key and value pair

Index of examples

Create a new tag for the existing application. For example, add an Tag to Html

Use a tag to represent another tag to help separation different text logically for example, use Indent to replace BackQuote

Use a tag to represent multiple tags, like company

[do reflection]

While XSLT can do [something], it lack of the functionality of [some other things]. And, XSLT's pattern driven design make something impossible/hard to do. for example,

[complicate table].

[do site management]