org.jdom2
Class Verifier

java.lang.Object
  org.jdom2.Verifier

public final class Verifier
extends java.lang.Object

A utility class to handle well-formedness checks on names, data, and other verification tasks for JDOM. The class is final and may not be subclassed.

Author:

Brett McLaughlin, Elliotte Rusty Harold, Jason Hunter, Bradley S. Huffman, Rolf Lear, Wilfried Middleton

Method Summary

static java.lang.String	checkAttributeName(java.lang.String name) This will check the supplied name to see if it is legal for use as a JDOM Attribute name.
static java.lang.String	checkCDATASection(java.lang.String data) This will check the supplied data to see if it is legal for use as JDOM CDATA.
static java.lang.String	checkCharacterData(java.lang.String text) This will check the supplied string to see if it only contains characters allowed by the XML 1.0 specification.
static java.lang.String	checkCommentData(java.lang.String data) This will check the supplied data to see if it is legal for use as JDOM Comment data.
static java.lang.String	checkElementName(java.lang.String name) This will check the supplied name to see if it is legal for use as a JDOM Element name.
static java.lang.String	checkNamespaceCollision(Attribute attribute, Element element) Check if Attribute's namespace collides with a Element's namespace.
static java.lang.String	checkNamespaceCollision(Attribute attribute, Element element, int ignoreatt) Check if Attribute's namespace collides with a Element's namespace.
static java.lang.String	checkNamespaceCollision(Namespace namespace, Attribute attribute) Check if a Namespace collides with a Attribute's namespace.
static java.lang.String	checkNamespaceCollision(Namespace namespace, Element element) Check if a Namespace collides with a Element's namespace.
static java.lang.String	checkNamespaceCollision(Namespace namespace, Element element, int ignoreatt) Check if a Namespace collides with a Element's namespace.
static java.lang.String	checkNamespaceCollision(Namespace namespace, java.util.List<?> list) Check if a Namespace collides with any namespace from a list of objects.
static java.lang.String	checkNamespaceCollision(Namespace namespace, java.util.List<?> list, int ignoreatt) Check if a Namespace collides with any namespace from a list of objects.
static java.lang.String	checkNamespaceCollision(Namespace namespace, Namespace other) Check if two namespaces collide.
static java.lang.String	checkNamespacePrefix(java.lang.String prefix) This will check the supplied name to see if it is legal for use as a JDOM Namespace prefix.
static java.lang.String	checkNamespaceURI(java.lang.String uri) This will check the supplied name to see if it is legal for use as a JDOM Namespace URI.
static java.lang.String	checkProcessingInstructionData(java.lang.String data) This will check the supplied data to see if it is legal for use as ProcessingInstruction data.
static java.lang.String	checkProcessingInstructionTarget(java.lang.String target) This will check the supplied data to see if it is legal for use as a JDOM ProcessingInstruction target.
static java.lang.String	checkPublicID(java.lang.String publicID) This will ensure that the data for a public identifier is legal.
static java.lang.String	checkSystemLiteral(java.lang.String systemLiteral) This will ensure that the data for a system literal is legal.
static java.lang.String	checkURI(java.lang.String uri) Checks a string to see if it is a legal RFC 2396 URI.
static java.lang.String	checkXMLName(java.lang.String name) This is a utility function for sharing the base process of checking any XML name.
static int	decodeSurrogatePair(char high, char low) This is a utility function to decode a non-BMP UTF-16 surrogate pair.
static boolean	isAllXMLWhitespace(java.lang.String value) This is a utility function for determining whether a specified String is a whitespace character according to production 3 of the XML 1.0 specification.
static boolean	isHexDigit(char c) This is a utility function for determining whether a specified Unicode character is a hexadecimal digit as defined in RFC 2396; that is, one of the ASCII characters 0-9, a-f, or A-F.
static boolean	isHighSurrogate(char ch) This is a function for determining whether the specified character is the high 16 bits in a UTF-16 surrogate pair.
static boolean	isLowSurrogate(char ch) This is a function for determining whether the specified character is the low 16 bits in a UTF-16 surrogate pair.
static boolean	isURICharacter(char c) This is a utility function for determining whether a specified Unicode character is legal in URI references as determined by RFC 2396.
static boolean	isXMLCharacter(int c) This is a utility function for determining whether a specified character is a character according to production 2 of the XML 1.0 specification.
static boolean	isXMLCombiningChar(char c) This is a utility function for determining whether a specified character is a combining character according to production 87 of the XML 1.0 specification.
static boolean	isXMLDigit(char c) This is a utility function for determining whether a specified Unicode character is a digit according to production 88 of the XML 1.0 specification.
static boolean	isXMLExtender(char c) This is a utility function for determining whether a specified character is an extender according to production 88 of the XML 1.0 specification.
static boolean	isXMLLetter(char c) This is a utility function for determining whether a specified character is a letter according to production 84 of the XML 1.0 specification.
static boolean	isXMLLetterOrDigit(char c) This is a utility function for determining whether a specified character is a letter or digit according to productions 84 and 88 of the XML 1.0 specification.
static boolean	isXMLNameCharacter(char c) This is a utility function for determining whether a specified character is a name character according to production 4 of the XML 1.0 specification.
static boolean	isXMLNameStartCharacter(char c) This is a utility function for determining whether a specified character is a legal name start character according to production 5 of the XML 1.0 specification.
static boolean	isXMLPublicIDCharacter(char c) This will check the supplied data to see if it is legal for use as PublicID (in a DocType or EntityRef).
static boolean	isXMLWhitespace(char c) This is a utility function for determining whether a specified Unicode character is a whitespace character according to production 3 of the XML 1.0 specification.

Methods inherited from class java.lang.Object

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

Method Detail

checkElementName

public static java.lang.String checkElementName(java.lang.String name)

This will check the supplied name to see if it is legal for use as a JDOM Element name.

Parameters:

name - String name to check.

Returns:

String reason name is illegal, or null if name is OK.

checkAttributeName

public static java.lang.String checkAttributeName(java.lang.String name)

This will check the supplied name to see if it is legal for use as a JDOM Attribute name.

Parameters:

name - String name to check.

Returns:

String reason name is illegal, or null if name is OK.

checkCharacterData

public static java.lang.String checkCharacterData(java.lang.String text)

This will check the supplied string to see if it only contains characters allowed by the XML 1.0 specification. The C0 controls (e.g. null, vertical tab, form-feed, etc.) are specifically excluded except for carriage return, line-feed, and the horizontal tab. Surrogates are also excluded.

This method is useful for checking element content and attribute values. Note that characters like " and < are allowed in attribute values and element content. They will simply be escaped as " or < when the value is serialized.

Parameters:

text - String value to check.

Returns:

String reason name is illegal, or null if name is OK.

checkCDATASection

public static java.lang.String checkCDATASection(java.lang.String data)

This will check the supplied data to see if it is legal for use as JDOM CDATA.

Parameters:

data - String data to check.

Returns:

String reason data is illegal, or null is name is OK.

checkNamespacePrefix

public static java.lang.String checkNamespacePrefix(java.lang.String prefix)

This will check the supplied name to see if it is legal for use as a JDOM Namespace prefix.

Parameters:

prefix - String prefix to check.

Returns:

String reason name is illegal, or null if name is OK.

checkNamespaceURI

public static java.lang.String checkNamespaceURI(java.lang.String uri)

This will check the supplied name to see if it is legal for use as a JDOM Namespace URI.

This is a 'light' test of URI's designed to filter out only the worst illegal URIs. It tests only to ensure the first character is valid. A comprehensive URI validation process would be impractical.

Parameters:

uri - String URI to check.

Returns:

String reason name is illegal, or null if name is OK.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Namespace namespace,
                                                       Namespace other)

Check if two namespaces collide.

Parameters:

namespace - Namespace to check.

other - Namespace to check against.

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Attribute attribute,
                                                       Element element)

Check if Attribute's namespace collides with a Element's namespace.

Parameters:

attribute - Attribute to check.

element - Element to check against.

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Attribute attribute,
                                                       Element element,
                                                       int ignoreatt)

Check if Attribute's namespace collides with a Element's namespace.

Parameters:

attribute - Attribute to check.

element - Element to check against.

ignoreatt - Ignore a specific Attribute (if it exists) when calculating any collisions (used when replacing one attribute with another).

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Namespace namespace,
                                                       Element element)

Check if a Namespace collides with a Element's namespace.

Parameters:

namespace - Namespace to check.

element - Element to check against.

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Namespace namespace,
                                                       Element element,
                                                       int ignoreatt)

Check if a Namespace collides with a Element's namespace.

Parameters:

namespace - Namespace to check.

element - Element to check against.

ignoreatt - Ignore a specific Attribute (if it exists) when calculating any collisions (used when replacing one attribute with another).

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Namespace namespace,
                                                       Attribute attribute)

Check if a Namespace collides with a Attribute's namespace.

Parameters:

namespace - Namespace to check.

attribute - Attribute to check against.

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Namespace namespace,
                                                       java.util.List<?> list)

Check if a Namespace collides with any namespace from a list of objects.

Parameters:

namespace - Namespace to check.

list - List to check against.

Returns:

String reason for collision, or null if no collision.

checkNamespaceCollision

public static java.lang.String checkNamespaceCollision(Namespace namespace,
                                                       java.util.List<?> list,
                                                       int ignoreatt)

Check if a Namespace collides with any namespace from a list of objects.

Parameters:

namespace - Namespace to check.

list - List to check against.

ignoreatt - Ignore a specific Attribute (if it exists) when calculating any collisions (used when replacing one attribute with another).

Returns:

String reason for collision, or null if no collision.

checkProcessingInstructionTarget

public static java.lang.String checkProcessingInstructionTarget(java.lang.String target)

This will check the supplied data to see if it is legal for use as a JDOM ProcessingInstruction target.

Parameters:

target - String target to check.

Returns:

String reason target is illegal, or null if target is OK.

checkProcessingInstructionData

public static java.lang.String checkProcessingInstructionData(java.lang.String data)

This will check the supplied data to see if it is legal for use as ProcessingInstruction data. Besides checking that all the characters are allowed in XML, this also checks that the data does not contain the PI end-string "?>".

Parameters:

data - String data to check.

Returns:

String reason data is illegal, or null if data is OK.

checkCommentData

public static java.lang.String checkCommentData(java.lang.String data)

This will check the supplied data to see if it is legal for use as JDOM Comment data.

Parameters:

data - String data to check.

Returns:

String reason data is illegal, or null if data is OK.

decodeSurrogatePair

public static int decodeSurrogatePair(char high,
                                      char low)

This is a utility function to decode a non-BMP UTF-16 surrogate pair.

Parameters:

high - high 16 bits

low - low 16 bits

Returns:

decoded character

isXMLPublicIDCharacter

public static boolean isXMLPublicIDCharacter(char c)

This will check the supplied data to see if it is legal for use as PublicID (in a DocType or EntityRef).

Parameters:

c - the character to validate

Returns:

String reason c is illegal, or null if c is OK.

checkPublicID

public static java.lang.String checkPublicID(java.lang.String publicID)

This will ensure that the data for a public identifier is legal.

Parameters:

publicID - String public ID to check.

Returns:

String reason public ID is illegal, or null if public ID is OK.

checkSystemLiteral

public static java.lang.String checkSystemLiteral(java.lang.String systemLiteral)

This will ensure that the data for a system literal is legal.

Parameters:

systemLiteral - String system literal to check.

Returns:

String reason system literal is illegal, or null if system literal is OK.

checkXMLName

public static java.lang.String checkXMLName(java.lang.String name)

This is a utility function for sharing the base process of checking any XML name.

Parameters:

name - String to check for XML name compliance.

Returns:

String reason the name is illegal, or null if OK.

checkURI

public static java.lang.String checkURI(java.lang.String uri)

Checks a string to see if it is a legal RFC 2396 URI. Both absolute and relative URIs are supported.

Parameters:

uri - String to check.

Returns:

String reason the URI is illegal, or null if OK.

isHexDigit

public static boolean isHexDigit(char c)

This is a utility function for determining whether a specified Unicode character is a hexadecimal digit as defined in RFC 2396; that is, one of the ASCII characters 0-9, a-f, or A-F.

Parameters:

c - to check for hex digit.

Returns:

true if it's allowed, false otherwise.

isHighSurrogate

public static boolean isHighSurrogate(char ch)

This is a function for determining whether the specified character is the high 16 bits in a UTF-16 surrogate pair.

Parameters:

ch - character to check

Returns:

true if the character is a high surrogate, false otherwise

isLowSurrogate

public static boolean isLowSurrogate(char ch)

This is a function for determining whether the specified character is the low 16 bits in a UTF-16 surrogate pair.

Parameters:

ch - character to check

Returns:

true if the character is a low surrogate, false otherwise.

isURICharacter

public static boolean isURICharacter(char c)

This is a utility function for determining whether a specified Unicode character is legal in URI references as determined by RFC 2396.

Parameters:

c - char to check for URI reference compliance.

Returns:

true if it's allowed, false otherwise.

isXMLCharacter

public static boolean isXMLCharacter(int c)

This is a utility function for determining whether a specified character is a character according to production 2 of the XML 1.0 specification.

Parameters:

c - char to check for XML compliance

Returns:

boolean true if it's a character, false otherwise

isXMLNameCharacter

public static boolean isXMLNameCharacter(char c)

This is a utility function for determining whether a specified character is a name character according to production 4 of the XML 1.0 specification.

Parameters:

c - char to check for XML name compliance.

Returns:

boolean true if it's a name character, false otherwise.

isXMLNameStartCharacter

public static boolean isXMLNameStartCharacter(char c)

This is a utility function for determining whether a specified character is a legal name start character according to production 5 of the XML 1.0 specification. This production does allow names to begin with colons which the Namespaces in XML Recommendation disallows.

Parameters:

c - char to check for XML name start compliance.

Returns:

boolean true if it's a name start character, false otherwise.

isXMLLetterOrDigit

public static boolean isXMLLetterOrDigit(char c)

This is a utility function for determining whether a specified character is a letter or digit according to productions 84 and 88 of the XML 1.0 specification.

Parameters:

c - char to check.

Returns:

boolean true if it's letter or digit, false otherwise.

isXMLLetter

public static boolean isXMLLetter(char c)

This is a utility function for determining whether a specified character is a letter according to production 84 of the XML 1.0 specification.

Parameters:

c - char to check for XML name compliance.

Returns:

String true if it's a letter, false otherwise.

isXMLCombiningChar

public static boolean isXMLCombiningChar(char c)

This is a utility function for determining whether a specified character is a combining character according to production 87 of the XML 1.0 specification.

Parameters:

c - char to check.

Returns:

boolean true if it's a combining character, false otherwise.

isXMLExtender

public static boolean isXMLExtender(char c)

This is a utility function for determining whether a specified character is an extender according to production 88 of the XML 1.0 specification.

Parameters:

c - char to check.

Returns:

String true if it's an extender, false otherwise.

isXMLDigit

public static boolean isXMLDigit(char c)

This is a utility function for determining whether a specified Unicode character is a digit according to production 88 of the XML 1.0 specification.

Parameters:

c - char to check for XML digit compliance

Returns:

boolean true if it's a digit, false otherwise

isXMLWhitespace

public static boolean isXMLWhitespace(char c)

This is a utility function for determining whether a specified Unicode character is a whitespace character according to production 3 of the XML 1.0 specification.

Parameters:

c - char to check for XML whitespace compliance

Returns:

boolean true if it's a whitespace, false otherwise

isAllXMLWhitespace

public static final boolean isAllXMLWhitespace(java.lang.String value)

This is a utility function for determining whether a specified String is a whitespace character according to production 3 of the XML 1.0 specification.

This method delegates the individual calls for each character to isXMLWhitespace(char).

Parameters:

value - The value to inspect

Returns:

true if all characters in the input value are all whitespace (or the string is the empty-string).

Since:

JDOM2