Apache™ FOP Development: RTFLib (jfor)
General Information
Introduction
The RTFLib package is an open-source, independent package suitable for writing RTF files in a java environment. By independent we mean:
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Although it is used by Apache™ FOP to generate FOP's RTF output, it is not dependent on FOP for any of its functionality.
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It does not require FOP as a front-end, nor does it even require XSL-FO for input. It essentially exposes an API of relatively high-level RTF construction routines to a host program. This means it can be used anywhere RTF output is required and java is available.
The FOP development team intends to keep the RTFLib package independent so that it can be used for other purposes.
History
RTFLib was originally developed by Bertrand Delacrétaz and the jfor team. jfor was written under an Apache-style license, and the jfor team contributed the code to the Apache Software Foundation in June, 2003. RTFLib is a subset of the original jfor project, which also includes an XSL-FO parsing mechanism for a complete XSL-FO to RTF solution.
Status
Although FOP's implementation of the RTFLib package is very incomplete, the RTFLib package itself is relatively mature. RTFLib is only available in the main line of FOP development.
User Documentation
Overview
Perhaps the easiest way to see how to use RTFLib is by looking at an example. A set of test documents is part of the package, and can be viewed online. A quick look at the Abstract TestDocument class, and one of the Concrete subclasses, SimpleDocument will provide the basics of how to use the package.
There are two basic concepts you will need to understand in order to use RTFLib:
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Documents are created by filling bigger containers with successively smaller containers, and eventually with content.
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Attributes may be set for each container or content as it is created
RTFLib handles the process of converting to and writing the RTF content as the document is created. All you need to do is flush the document at the end to make sure that the last pieces get written.
Document Structure
The following table summarizes the various containers that can be created:
| Name | Class.Method where created | Attribute Set(s) | Valid children |
|---|---|---|---|
| Document Area | RtfFile.startDocumentArea() | Information Group, Document Formatting | Section |
| Section | RtfDocumentArea.newSection() | Section Formatting | Paragraph, ParagraphKeepTogether, Image, List, Before (Page Heading), After (Page Footer), JforCmd |
| Paragraph | RtfSection.newParagraph() | Paragraph Formatting, Character Formatting | Text |
| ParagraphKeepTogether | RtfSection.newParagraphKeepTogether | . | . |
| Image | RtfSection.newImage | . | . |
| Table | RtfSection.newTable | . | . |
| List | RtfSection.newList | . | . |
| Before (Page Heading) | RtfSection.newBefore | . | . |
| After (Page Footer) | RtfSection.newAfter | . | . |
| JforCmd | RtfSection.newJforCmd | . | . |
| Text | RtfParagraph.newText() | Character Formatting | N/A |
Attributes
Information Group
These attributes are set when creating a Document.
Document Formatting
These attributes are set when creating a Document.
Section Formatting
These attributes are set when creating a Section.
Paragraph Formatting
These attributes are set when creating a Paragraph.
| Description | Attribute Name | Attribute Value | RTF Control Word |
|---|---|---|---|
| . | |||
| Alignment | . | ||
| ----------- | --- | ||
| Align Left | RtfText.ALIGN_LEFT | N/A (boolean) | \ql |
| Align Right | RtfText.ALIGN_RIGHT | N/A (boolean) | \qr |
| Align Centered | RtfText.ALIGN_CENTER | N/A (boolean) | \qc |
| Align Justified | RtfText.ALIGN_JUSTIFIED | N/A (boolean) | \qj |
| Align Distributed | RtfText.ALIGN_DISTRIBUTED | N/A (boolean) | \qd |
| Kashida justification | not implemented | 0-20 (integer) | \qkN |
| Thai Distributed justification | not implemented | N/A (boolean) | \qt |
| Indentation | . | ||
| ------------- | --- | ||
| Left indent body | RtfText.LEFT_INDENT_BODY | (int) "hundredths of a character unit" (?) | \li |
| Left indent first | RtfText.LEFT_INDENT_FIRST | (int) "hundredths of a character unit" (?) | \fi |
| Borders | . | ||
| --------- | --- | ||
| Bottom single border | RtfText.BDR_BOTTOM_SINGLE | Boolean? | brdrb\brsp40\brdrs |
| Bottom double border | RtfText.BDR_BOTTOM_DOUBLE | Boolean? | brdrb\brsp40\brdrdb |
| Bottom embossed border | RtfText.BDR_BOTTOM_EMBOSS | Boolean? | brdrb\brsp40\brdremboss |
| bottom dotted border | RtfText.BDR_BOTTOM_DOTTED | Boolean? | brdrb\brsp40\brdrdot |
| bottom dashed border | RtfText.BDR_BOTTOM_DASH | Boolean? | brdrb\brsp40\brdrdash |
Character Formatting
These attributes are set when creating a Paragraph, or Text.
| Description | Attribute Name | Attribute Value | RTF Control Word |
|---|---|---|---|
| Bold | RtfText.ATTR_BOLD | N/A (boolean) | \b |
| Italic | RtfText.ATTR_ITALIC | N/A (boolean) | \i |
| Underline | RtfText.ATTR_UNDERLINE | N/A (boolean), or (int) 0 to turn underlining off | \ul |
| Font Size | RtfText.ATTR_FONT_SIZE | (int) font size in half-points | \fs |
| Font Family | RtfText.ATTR_FONT_FAMILY | (int) entry in document font-table | \f |
| Font Color | RtfText.ATTR_FONT_COLOR | (int) entry in document color-table | \cf |
| Background Color | RtfText.ATTR_BACKGROUND_COLOR | (int) entry in document color-table | \chcbpat |