Class XMLChar


  • public class XMLChar
    extends 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:
    $Id$
    Author:
    Glenn Marcy, IBM, Andy Clark, IBM, Eric Ye, IBM, Arnaud Le Hors, IBM, Michael Glavassevich, IBM, Rahul Srivastava, Sun Microsystems Inc.
    • Constructor Summary

      Constructors 
      Constructor Description
      XMLChar()  
    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      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​(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 isValidName​(String name)
      Check to see if a string is a valid Name according to [5] in the XML 1.0 Recommendation
      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 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.
      static String trim​(String value)
      Trims space characters as defined by production [3] in the XML 1.0 specification from both ends of the given string.
    • Field Detail

      • MASK_NAME_START

        public static final int MASK_NAME_START
        Name start 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​(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​(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​(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​(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.
      • trim

        public static String trim​(String value)
        Trims space characters as defined by production [3] in the XML 1.0 specification from both ends of the given string.
        Parameters:
        value - the string to be trimmed
        Returns:
        the given string with the space characters trimmed from both ends