org.apache.xml.utils
Class XMLChar

java.lang.Object
  org.apache.xml.utils.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.

Field Summary

private static byte[]	CHARS Character flags.
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.

Constructor Summary

XMLChar()

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	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	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	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(java.lang.String ianaEncoding) Returns true if the encoding name is a valid IANA encoding.
static boolean	isValidJavaEncoding(java.lang.String javaEncoding) Returns true if the encoding name is a valid Java encoding.
static boolean	isValidName(java.lang.String name) Check to see if a string is a valid Name according to [5] in the XML 1.0 Recommendation
static boolean	isValidNCName(java.lang.String ncName) Check to see if a string is a valid NCName according to [4] from the XML Namespaces 1.0 Recommendation
static boolean	isValidNmtoken(java.lang.String nmtoken) Check to see if a string is a valid Nmtoken according to [7] in the XML 1.0 Recommendation
static boolean	isValidQName(java.lang.String str) Simple check to determine if qname is legal.
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.

Methods inherited from class java.lang.Object

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

Field Detail

CHARS

private static final byte[] CHARS

Character flags.

MASK_VALID

public static final int MASK_VALID

Valid character mask.

See Also:

Constant Field Values

MASK_SPACE

public static final int MASK_SPACE

Space character mask.

See Also:

Constant Field Values

MASK_NAME_START

public static final int MASK_NAME_START

Name start character mask.

See Also:

Constant Field Values

MASK_NAME

public static final int MASK_NAME

Name character mask.

See Also:

Constant Field Values

MASK_PUBID

public static final int MASK_PUBID

Pubid character mask.

See Also:

Constant Field Values

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.

See Also:

Constant Field Values

MASK_NCNAME_START

public static final int MASK_NCNAME_START

NCName start character mask.

See Also:

Constant Field Values

MASK_NCNAME

public static final int MASK_NCNAME

NCName character mask.

See Also:

Constant Field Values

Constructor Detail

XMLChar

public XMLChar()

Method Detail

isSupplemental

public static boolean isSupplemental(int c)

Returns true if the specified character is a supplemental character.

Parameters:

c - The character to check.

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.

highSurrogate

public static char highSurrogate(int c)

Returns the high surrogate of a supplemental character

Parameters:

c - The supplemental character to "split".

lowSurrogate

public static char lowSurrogate(int c)

Returns the low surrogate of a supplemental character

Parameters:

c - The supplemental character to "split".

isHighSurrogate

public static boolean isHighSurrogate(int c)

Returns whether the given character is a high surrogate

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.

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.

isInvalid

public static boolean isInvalid(int c)

Returns true if the specified character is invalid.

Parameters:

c - The character to check.

isContent

public static boolean isContent(int c)

Returns true if the specified character can be considered content.

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.

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.

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.

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.

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.

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.

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.

isValidName

public static boolean isValidName(java.lang.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

isValidNCName

public static boolean isValidNCName(java.lang.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

isValidNmtoken

public static boolean isValidNmtoken(java.lang.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

isValidIANAEncoding

public static boolean isValidIANAEncoding(java.lang.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(java.lang.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.

isValidQName

public static boolean isValidQName(java.lang.String str)

Simple check to determine if qname is legal. If it returns false then str is illegal; if it returns true then str is legal.