com.nwalsh.saxon

Class NumberLinesEmitter


public class NumberLinesEmitter
extends CopyEmitter

Saxon extension to decorate a result tree fragment with line numbers.

$Id: NumberLinesEmitter.java 5907 2006-04-27 08:26:47Z xmldoc $

Copyright (C) 2000 Norman Walsh.

This class provides the guts of a Saxon 6.* implementation of line numbering for verbatim environments. (It is used by the Verbatim class.)

The general design is this: the stylesheets construct a result tree fragment for some verbatim environment. The Verbatim class initializes a NumberLinesEmitter with information about what lines should be numbered and how. Then the result tree fragment is "replayed" through the NumberLinesEmitter; the NumberLinesEmitter builds a new result tree fragment from this event stream, decorated with line numbers, and that is returned.

Change Log:

See Also:
Verbatim

Field Summary

protected Stack
elementStack
A stack for the preserving information about open elements.
protected boolean
firstElement
Is the next element absolutely the first element in the fragment?
protected boolean
foStylesheet
Is the stylesheet currently running an FO stylesheet?
protected static String
foURI
The FO namespace name.
protected int
lineNumber
The current line number.
protected int
modulus
Every modulus line will be numbered.
protected String
separator
Line numbers are separated from the listing by separator.
protected int
startinglinenumber
The first line number will be startinglinenumber.
protected int
width
Line numbers are width characters wide.
protected static String
xhURI
The XHTML namespace name.

Fields inherited from class com.nwalsh.saxon.CopyEmitter

namePool, rtf, rtfEmitter

Constructor Summary

NumberLinesEmitter(Controller controller, NamePool namePool, int startingLineNumber, int modulus, int width, String separator, boolean foStylesheet)
Constructor for the NumberLinesEmitter.

Method Summary

void
characters(char[] chars, int start, int len)
Process characters.
void
endElement(int nameCode)
Process end element events.
protected void
formatLineNumber(int lineNumber)
Add a formatted line number to the result tree fragment.
protected boolean
skipThisElement(int nameCode)
Protect the outer-most block wrapper.
void
startElement(int nameCode, org.xml.sax.Attributes attributes, int[] namespaces, int nscount)
Process start element events.

Methods inherited from class com.nwalsh.saxon.CopyEmitter

characters, comment, endDocument, endElement, getResultTreeFragment, processingInstruction, setDocumentLocator, setEscaping, setNamePool, setUnparsedEntity, setWriter, startDocument, startElement

Field Details

elementStack

protected Stack elementStack
A stack for the preserving information about open elements.

firstElement

protected boolean firstElement
Is the next element absolutely the first element in the fragment?

foStylesheet

protected boolean foStylesheet
Is the stylesheet currently running an FO stylesheet?

foURI

protected static String foURI
The FO namespace name.

lineNumber

protected int lineNumber
The current line number.

modulus

protected int modulus
Every modulus line will be numbered.

separator

protected String separator
Line numbers are separated from the listing by separator.

startinglinenumber

protected int startinglinenumber
The first line number will be startinglinenumber.

width

protected int width
Line numbers are width characters wide.

xhURI

protected static String xhURI
The XHTML namespace name.

Constructor Details

NumberLinesEmitter

public NumberLinesEmitter(Controller controller,
                          NamePool namePool,
                          int startingLineNumber,
                          int modulus,
                          int width,
                          String separator,
                          boolean foStylesheet)
Constructor for the NumberLinesEmitter.
Parameters:
namePool - The name pool to use for constructing elements and attributes.
modulus - The modulus to use for this listing.
width - The width to use for line numbers in this listing.
separator - The separator to use for this listing.
foStylesheet - Is this an FO stylesheet?

Method Details

characters

public void characters(char[] chars,
                       int start,
                       int len)
            throws TransformerException
Process characters.
Overrides:
characters in interface CopyEmitter

endElement

public void endElement(int nameCode)
            throws TransformerException
Process end element events.
Overrides:
endElement in interface CopyEmitter

formatLineNumber

protected void formatLineNumber(int lineNumber)
            throws TransformerException
Add a formatted line number to the result tree fragment.
Parameters:
lineNumber - The number of the current line.

skipThisElement

protected boolean skipThisElement(int nameCode)
Protect the outer-most block wrapper.

Open elements in the result tree fragment are closed and reopened around callouts (so that callouts don't appear inside links or other environments). But if the result tree fragment is a single block (a div or pre in HTML, an fo:block in FO), that outer-most block is treated specially.

This method returns true if the element in question is that outermost block.

Parameters:
nameCode - The name code for the element
Returns:
True if the element is the outer-most block, false otherwise.

startElement

public void startElement(int nameCode,
                         org.xml.sax.Attributes attributes,
                         int[] namespaces,
                         int nscount)
            throws TransformerException
Process start element events.
Overrides:
startElement in interface CopyEmitter