Class XMLChar

java.lang.Object
org.apache.jena.util.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: XMLChar.java 674378 2008-07-07 00:52:45Z mrglavas $
Author:
Glenn Marcy, IBM, Andy Clark, IBM, Eric Ye, IBM, Arnaud Le Hors, IBM, Michael Glavassevich, IBM, Rahul Srivastava, Sun Microsystems Inc.
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    Content character mask.
    static final int
    Name character mask.
    static final int
    Name start character mask.
    static final int
    NCName character mask.
    static final int
    NCName start character mask.
    static final int
    Pubid character mask.
    static final int
    Space character mask.
    static final int
    Valid character mask.
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    static char
    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
    Returns whether the given character is a high surrogate
    static boolean
    isInvalid(int c)
    Returns true if the specified character is invalid.
    static boolean
    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
    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
    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
    Returns true if the encoding name is a valid IANA encoding.
    static boolean
    Returns true if the encoding name is a valid Java encoding.
    static boolean
    Check to see if a string is a valid Name according to [5] in the XML 1.0 Recommendation
    static boolean
    Check to see if a string is a valid NCName according to [4] from the XML Namespaces 1.0 Recommendation
    static boolean
    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.

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Field Details

    • MASK_VALID

      public static final int MASK_VALID
      Valid character mask.
      See Also:
    • MASK_SPACE

      public static final int MASK_SPACE
      Space character mask.
      See Also:
    • MASK_NAME_START

      public static final int MASK_NAME_START
      Name start character mask.
      See Also:
    • MASK_NAME

      public static final int MASK_NAME
      Name character mask.
      See Also:
    • MASK_PUBID

      public static final int MASK_PUBID
      Pubid character mask.
      See Also:
    • 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:
    • MASK_NCNAME_START

      public static final int MASK_NCNAME_START
      NCName start character mask.
      See Also:
    • MASK_NCNAME

      public static final int MASK_NCNAME
      NCName character mask.
      See Also:
  • Constructor Details

    • XMLChar

      public XMLChar()
  • Method Details

    • 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