fi.iki.hsivonen.xml.checker
Class NormalizationChecker

java.lang.Object
  fi.iki.hsivonen.xml.checker.Checker
      fi.iki.hsivonen.xml.checker.NormalizationChecker

All Implemented Interfaces:

ContentHandler

public final class NormalizationChecker
extends Checker

Checks that the following constructs do not start with a composing character:

• Local names of elements
• Local names of attributes
• Attribute values
• Declared namespace prefixes
• Declared namespace URIs
• PI targets
• PI data
• Concatenations of consecutive character data between element boundaries and PIs ignoring comments and CDATA section boundaries.

Checks that the following constructs are in the Unicode Normalization Form C. (It is assumed the normalization of the rest of the constructs is enforced by other means, such as checking the document source for normalization.)

• Attribute values
• PI data
• Concatenations of consecutive character data between element boundaries and PIs ignoring comments and CDATA section boundaries.

All Strings must be valid UTF-16!

This class can also be used as a source code mode where the source code of the document is fed to characters(). The mode modifies the error messages appropriately.

Version:

$Id: NormalizationChecker.java,v 1.6 2006/12/01 12:34:31 hsivonen Exp $

Author:

hsivonen

Field Summary

private boolean	alreadyComplainedAboutThisRun Indicates whether the current run has already caused an error.
private boolean	atStartOfRun Indicates whether the checker the next call to characters() is the first call in a run.
private char[]	buf A buffer for holding sequences overlap the SAX buffer boundary.
private char[]	bufHolder A holder for the original buffer (for the memory leak prevention mechanism).
private static com.ibm.icu.text.UnicodeSet	COMPOSING_CHARACTERS A thread-safe set of composing characters as per Charmod Norm.
private int	pos The current used length of the buffer, i.e.
private boolean	sourceTextMode Indicates whether error messages related to source code checking should be used.

Constructor Summary

NormalizationChecker()
Constructor for non-source mode.

NormalizationChecker(boolean sourceTextMode)
Constructor with mode selection.

Method Summary

private void	appendToBuf(char[] ch, int start, int end) Appends a slice of an UTF-16 code unit array to the internal buffer.
void	characters(char[] ch, int start, int length) In the normal mode, this method has the usual SAX semantics.
void	endElement(String uri, String localName, String qName)
private void	errAboutTextRun() Emits an error stating that the current text run or the source text is not in NFC.
void	flush() Called to indicate the end of a run of characters.
private static boolean	isComposingChar(int c) Returns true if the argument is a composing character and false otherwise.
private static boolean	isComposingCharOrSurrogate(char c) Returns true if the argument is a composing BMP character or a surrogate and false otherwise.
void	processingInstruction(String target, String data)
void	reset() Does nothing.
void	startElement(String uri, String localName, String qName, Attributes atts)
void	startPrefixMapping(String prefix, String uri)
static boolean	startsWithComposingChar(String str) Returns true if the argument starts with a composing character and false otherwise.

Methods inherited from class fi.iki.hsivonen.xml.checker.Checker

endDocument, endPrefixMapping, err, getDocumentLocator, getErrorHandler, ignorableWhitespace, setDocumentLocator, setErrorHandler, skippedEntity, startDocument, warn

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

COMPOSING_CHARACTERS

private static final com.ibm.icu.text.UnicodeSet COMPOSING_CHARACTERS

A thread-safe set of composing characters as per Charmod Norm.

buf

private char[] buf

A buffer for holding sequences overlap the SAX buffer boundary.

bufHolder

private char[] bufHolder

A holder for the original buffer (for the memory leak prevention mechanism).

pos

private int pos

The current used length of the buffer, i.e. the index of the first slot that does not hold current data.

atStartOfRun

private boolean atStartOfRun

Indicates whether the checker the next call to characters() is the first call in a run.

alreadyComplainedAboutThisRun

private boolean alreadyComplainedAboutThisRun

Indicates whether the current run has already caused an error.

sourceTextMode

private final boolean sourceTextMode

Indicates whether error messages related to source code checking should be used.

Constructor Detail

NormalizationChecker

public NormalizationChecker()

Constructor for non-source mode.

NormalizationChecker

public NormalizationChecker(boolean sourceTextMode)

Constructor with mode selection.

Parameters:

sourceTextMode - whether the source text-related messages should be enabled.

Method Detail

isComposingCharOrSurrogate

private static boolean isComposingCharOrSurrogate(char c)

Returns true if the argument is a composing BMP character or a surrogate and false otherwise.

Parameters:

c - a UTF-16 code unit

Returns:

true if the argument is a composing BMP character or a surrogate and false otherwise

isComposingChar

private static boolean isComposingChar(int c)

Returns true if the argument is a composing character and false otherwise.

Parameters:

c - a Unicode code point

Returns:

true if the argument is a composing character false otherwise

startsWithComposingChar

public static boolean startsWithComposingChar(String str)
                                       throws SAXException

Returns true if the argument starts with a composing character and false otherwise.

Parameters:

str - a string

Returns:

true if the argument starts with a composing character and false otherwise.

Throws:

SAXException - on malformed UTF-16

reset

public void reset()

Description copied from class: Checker

Does nothing. Subclasses are expected to override this method with an implementation that clears the state of the checker and releases objects the checker might hold references to.

Overrides:

reset in class Checker

See Also:

Checker.reset()

characters

public void characters(char[] ch,
                       int start,
                       int length)
                throws SAXException

In the normal mode, this method has the usual SAX semantics. In the source text mode, this method is used for reporting the source text.

Specified by:

characters in interface ContentHandler

Overrides:

characters in class Checker

Throws:

SAXException

See Also:

Checker.characters(char[], int, int)

errAboutTextRun

private void errAboutTextRun()
                      throws SAXException

Emits an error stating that the current text run or the source text is not in NFC.

Throws:

SAXException - if the ErrorHandler throws

appendToBuf

private void appendToBuf(char[] ch,
                         int start,
                         int end)

Appends a slice of an UTF-16 code unit array to the internal buffer.

Parameters:

ch - the array from which to copy

start - the index of the first element that is copied

end - the index of the first element that is not copied

endElement

public void endElement(String uri,
                       String localName,
                       String qName)
                throws SAXException

Specified by:

endElement in interface ContentHandler

Overrides:

endElement in class Checker

Throws:

SAXException

See Also:

Checker.endElement(java.lang.String, java.lang.String, java.lang.String)

processingInstruction

public void processingInstruction(String target,
                                  String data)
                           throws SAXException

Specified by:

processingInstruction in interface ContentHandler

Overrides:

processingInstruction in class Checker

Throws:

SAXException

See Also:

Checker.processingInstruction(java.lang.String, java.lang.String)

startElement

public void startElement(String uri,
                         String localName,
                         String qName,
                         Attributes atts)
                  throws SAXException

Specified by:

startElement in interface ContentHandler

Overrides:

startElement in class Checker

Throws:

SAXException

See Also:

Checker.startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)

startPrefixMapping

public void startPrefixMapping(String prefix,
                               String uri)
                        throws SAXException

Specified by:

startPrefixMapping in interface ContentHandler

Overrides:

startPrefixMapping in class Checker

Throws:

SAXException

See Also:

Checker.startPrefixMapping(java.lang.String, java.lang.String)

flush

public void flush()
           throws SAXException

Called to indicate the end of a run of characters. When this class is used for checking source text, this method should be called after all the calls to characters().

Throws:

SAXException - if the ErrorHandler throws.