org.apache.xerces.util

Class XMLChar


public class XMLChar
extends java.lang.Object

This class defines the basic XML character properties. The data in this class can be used to verify that a character is a valid XML character or if the character is a space, name start, or name character.

A series of convenience methods are supplied to ease the burden of the developer. Because inlining the checks can improve per character performance, the tables of character properties are public. Using the character as an index into the CHARS array and applying the appropriate mask flag (e.g. MASK_VALID), yields the same results as calling the convenience methods. There is one exception: check the comments for the isValid method for details.

Version:
$Id: XMLChar.java 319864 2004-03-25 04:03:23Z mrglavas $
Authors:
Glenn Marcy, IBM
Andy Clark, IBM
Eric Ye, IBM
Arnaud Le Hors, IBM
Michael Glavassevich, IBM
Rahul Srivastava, Sun Microsystems Inc.

Field Summary

static int
MASK_CONTENT
Content character mask.
static int
MASK_NAME
Name character mask.
static int
MASK_NAME_START
Name start character mask.
static int
MASK_NCNAME
NCName character mask.
static int
MASK_NCNAME_START
NCName start character mask.
static int
MASK_PUBID
Pubid character mask.
static int
MASK_SPACE
Space character mask.
static int
MASK_VALID
Valid character mask.

Method Summary

static char
highSurrogate(int c)
Returns the high surrogate of a supplemental character
static boolean
isContent(int c)
Returns true if the specified character can be considered content.
static boolean
isHighSurrogate(int c)
Returns whether the given character is a high surrogate
static boolean
isInvalid(int c)
Returns true if the specified character is invalid.
static boolean
isLowSurrogate(int c)
Returns whether the given character is a low surrogate
static boolean
isMarkup(int c)
Returns true if the specified character can be considered markup.
static boolean
isNCName(int c)
Returns true if the specified character is a valid NCName character as defined by production [5] in Namespaces in XML recommendation.
static boolean
isNCNameStart(int c)
Returns true if the specified character is a valid NCName start character as defined by production [4] in Namespaces in XML recommendation.
static boolean
isName(int c)
Returns true if the specified character is a valid name character as defined by production [4] in the XML 1.0 specification.
static boolean
isNameStart(int c)
Returns true if the specified character is a valid name start character as defined by production [5] in the XML 1.0 specification.
static boolean
isPubid(int c)
Returns true if the specified character is a valid Pubid character as defined by production [13] in the XML 1.0 specification.
static boolean
isSpace(int c)
Returns true if the specified character is a space character as defined by production [3] in the XML 1.0 specification.
static boolean
isSupplemental(int c)
Returns true if the specified character is a supplemental character.
static boolean
isValid(int c)
Returns true if the specified character is valid.
static boolean
isValidIANAEncoding(String ianaEncoding)
Returns true if the encoding name is a valid IANA encoding.
static boolean
isValidJavaEncoding(String javaEncoding)
Returns true if the encoding name is a valid Java encoding.
static boolean
isValidNCName(String ncName)
Check to see if a string is a valid NCName according to [4] from the XML Namespaces 1.0 Recommendation
static boolean
isValidName(String name)
Check to see if a string is a valid Name according to [5] in the XML 1.0 Recommendation
static boolean
isValidNmtoken(String nmtoken)
Check to see if a string is a valid Nmtoken according to [7] in the XML 1.0 Recommendation
static char
lowSurrogate(int c)
Returns the low surrogate of a supplemental character
static int
supplemental(char h, char l)
Returns true the supplemental character corresponding to the given surrogates.

Field Details

MASK_CONTENT

public static final int MASK_CONTENT
Content character mask. Special characters are those that can be considered the start of markup, such as '<' and '&'. The various newline characters are considered special as well. All other valid XML characters can be considered content.

This is an optimization for the inner loop of character scanning.

Field Value:
32

MASK_NAME

public static final int MASK_NAME
Name character mask.
Field Value:
8

MASK_NAME_START

public static final int MASK_NAME_START
Name start character mask.
Field Value:
4

MASK_NCNAME

public static final int MASK_NCNAME
NCName character mask.
Field Value:
128

MASK_NCNAME_START

public static final int MASK_NCNAME_START
NCName start character mask.
Field Value:
64

MASK_PUBID

public static final int MASK_PUBID
Pubid character mask.
Field Value:
16

MASK_SPACE

public static final int MASK_SPACE
Space character mask.
Field Value:
2

MASK_VALID

public static final int MASK_VALID
Valid character mask.
Field Value:
1

Method Details

highSurrogate

public static char highSurrogate(int c)
Returns the high surrogate of a supplemental character
Parameters:
c - The supplemental character to "split".

isContent

public static boolean isContent(int c)
Returns true if the specified character can be considered content.
Parameters:
c - The character to check.

isHighSurrogate

public static boolean isHighSurrogate(int c)
Returns whether the given character is a high surrogate
Parameters:
c - The character to check.

isInvalid

public static boolean isInvalid(int c)
Returns true if the specified character is invalid.
Parameters:
c - The character to check.

isLowSurrogate

public static boolean isLowSurrogate(int c)
Returns whether the given character is a low surrogate
Parameters:
c - The character to check.

isMarkup

public static boolean isMarkup(int c)
Returns true if the specified character can be considered markup. Markup characters include '<', '&', and '%'.
Parameters:
c - The character to check.

isNCName

public static boolean isNCName(int c)
Returns true if the specified character is a valid NCName character as defined by production [5] in Namespaces in XML recommendation.
Parameters:
c - The character to check.

isNCNameStart

public static boolean isNCNameStart(int c)
Returns true if the specified character is a valid NCName start character as defined by production [4] in Namespaces in XML recommendation.
Parameters:
c - The character to check.

isName

public static boolean isName(int c)
Returns true if the specified character is a valid name character as defined by production [4] in the XML 1.0 specification.
Parameters:
c - The character to check.

isNameStart

public static boolean isNameStart(int c)
Returns true if the specified character is a valid name start character as defined by production [5] in the XML 1.0 specification.
Parameters:
c - The character to check.

isPubid

public static boolean isPubid(int c)
Returns true if the specified character is a valid Pubid character as defined by production [13] in the XML 1.0 specification.
Parameters:
c - The character to check.

isSpace

public static boolean isSpace(int c)
Returns true if the specified character is a space character as defined by production [3] in the XML 1.0 specification.
Parameters:
c - The character to check.

isSupplemental

public static boolean isSupplemental(int c)
Returns true if the specified character is a supplemental character.
Parameters:
c - The character to check.

isValid

public static boolean isValid(int c)
Returns true if the specified character is valid. This method also checks the surrogate character range from 0x10000 to 0x10FFFF.

If the program chooses to apply the mask directly to the CHARS array, then they are responsible for checking the surrogate character range.

Parameters:
c - The character to check.

isValidIANAEncoding

public static boolean isValidIANAEncoding(String ianaEncoding)
Returns true if the encoding name is a valid IANA encoding. This method does not verify that there is a decoder available for this encoding, only that the characters are valid for an IANA encoding name.
Parameters:
ianaEncoding - The IANA encoding name.

isValidJavaEncoding

public static boolean isValidJavaEncoding(String javaEncoding)
Returns true if the encoding name is a valid Java encoding. This method does not verify that there is a decoder available for this encoding, only that the characters are valid for an Java encoding name.
Parameters:
javaEncoding - The Java encoding name.

isValidNCName

public static boolean isValidNCName(String ncName)
Check to see if a string is a valid NCName according to [4] from the XML Namespaces 1.0 Recommendation
Parameters:
ncName - string to check
Returns:
true if name is a valid NCName

isValidName

public static boolean isValidName(String name)
Check to see if a string is a valid Name according to [5] in the XML 1.0 Recommendation
Parameters:
name - string to check
Returns:
true if name is a valid Name

isValidNmtoken

public static boolean isValidNmtoken(String nmtoken)
Check to see if a string is a valid Nmtoken according to [7] in the XML 1.0 Recommendation
Parameters:
nmtoken - string to check
Returns:
true if nmtoken is a valid Nmtoken

lowSurrogate

public static char lowSurrogate(int c)
Returns the low surrogate of a supplemental character
Parameters:
c - The supplemental character to "split".

supplemental

public static int supplemental(char h,
                               char l)
Returns true the supplemental character corresponding to the given surrogates.
Parameters:
h - The high surrogate.
l - The low surrogate.

Copyright B) 1999-2006 The Apache Software Foundation. All Rights Reserved.