uk.ac.sheffield.jast.xml

Class Markup

java.lang.Object

uk.ac.sheffield.jast.xml.Content

uk.ac.sheffield.jast.xml.Markup

All Implemented Interfaces:

java.lang.Cloneable, java.lang.Iterable<Content>

Direct Known Subclasses:

Attribute, Descriptor

public abstract class Markup
extends Content

Markup is the abstract ancestor of any named or tagged XML content. The different kinds of Markup include the obvious Element, Declaration, Instruction and Doctype nodes, but also include the Attribute node. All Markup-nodes are created with a distinguishing identifier, whose syntax is checked at creation. This identifier may be a single name token, or it may be split into a name and an optional namespace prefix, where the full identifier is formed by the concatenation: prefix:name. If present, the prefix is a short mnemonic referring to an XML namespace, and denotes the XML namespace to which this Markup belongs. Markup interns all three prefix, name and identifier symbols, since these may be used in various forms of search, which are optimised for identity-comparison.

Markup is distinguished from other kinds of Content, in that Markup nodes are identified by name, rather than by their content-type. It is possible to search for Markup either by name, by the full identifier, or by content-type. Markup offers the ability to search for the XML Namespace defining the Markup. This triggers a search in the document either for xmlns:abc attributes matching the prefix abc of this Markup, or for the default xmlns attribute, if no prefix is defined. If no given Namespace, or default Namespace is defined, this Markup formally belongs to the empty Namespace.

Version:

2.5

Author:

Anthony J H Simons

Field Summary

Fields

Modifier and Type	Field and Description
private java.lang.String	identifier The unique identifier of this Markup content.
private java.lang.String	name The short name of this Markup content.
private java.lang.String	prefix The namespace prefix of this Markup content.

Fields inherited from class uk.ac.sheffield.jast.xml.Content

ATTRIBUTE, COMMENT, DATA, DECLARATION, DOCTYPE, DOCUMENT, ELEMENT, INSTRUCTION, TEXT, UNDEFINED

Constructor Summary

Constructors

Constructor and Description
Markup(java.lang.String identifier) Creates a new Markup content with the given identifier or short name.
Markup(java.lang.String prefix, java.lang.String name) Creates a new Markup content with the given prefix and name.

Method Summary

Modifier and Type	Method and Description
java.lang.String	getIdentifier() Returns the identifier of this Markup content.
java.lang.String	getName() Returns the name of this Markup content.
Namespace	getNamespace() Returns the namespace associated with this Markup.
java.lang.String	getPrefix() Returns the prefix of this Markup content.
private void	invalidID(java.lang.String message, java.lang.String identifier) Throws a SyntaxError reporting a malformed or illegal identifier.
private void	setName(java.lang.String name) Secret method to validate XML name identifiers.
private void	setPrefix(java.lang.String prefix) Secret method to validate XML prefix identifiers.

Methods inherited from class uk.ac.sheffield.jast.xml.Content

addAttribute, addContent, addContent, clone, descendants, descendants, detach, getAttributes, getComment, getContent, getContent, getContent, getContents, getContents, getDocument, getParent, getText, getType, hasContents, iterator, iterator, removeContent, removeContent, removeContents, setParent, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

identifier

private java.lang.String identifier

The unique identifier of this Markup content. This is always initialised at construction and may not be null. If this Markup content has a namespace prefix, the identifier consists of the prefix, a colon and the name. Otherwise, the identifier is identical to the name. The identifier is an interned symbol.

prefix

private java.lang.String prefix

The namespace prefix of this Markup content. This is optional and may be provided if this Markup content is defined in a namespace. The prefix is an interned symbol.

name

private java.lang.String name

The short name of this Markup content. This is always initialised at construction and may not be null. The name is an interned symbol.

Constructor Detail

Markup

public Markup(java.lang.String identifier)
       throws SyntaxError

Creates a new Markup content with the given identifier or short name. The identifier may be a fully-qualified name (including the prefix), or a short name. If the identifier supplied contains a colon character ':', the part preceding the colon is treated as the prefix, and the part following as the short name. The identifier may not be null. If the identifier starts with a colon, the namespace is anonymous (the empty string).

Parameters:

identifier - the full identifier, or short name.

Throws:

SyntaxError - if the identifier is not a valid XML name token.

Markup

public Markup(java.lang.String prefix,
              java.lang.String name)
       throws SyntaxError

Creates a new Markup content with the given prefix and name. The identifier for this Markup content is formed by concatenating the symbols: prefix + ":" + name. Neither the prefix nor the name may be null.

Parameters:

prefix - the prefix relating to a namespace.

name - the local name of this Markup content.

Throws:

SyntaxError - if either the prefix or the name are not valid XML name tokens.

Method Detail

invalidID

private void invalidID(java.lang.String message,
                       java.lang.String identifier)
                throws SyntaxError

Throws a SyntaxError reporting a malformed or illegal identifier.

Parameters:

message - the error message.

identifier - the identifier, or null if empty.

Throws:

SyntaxError - deliberately.

setName

private void setName(java.lang.String name)
              throws SyntaxError

Secret method to validate XML name identifiers. The name must not be null, nor the empty string. It must start with a legal Unicode (letter) character and must continue with legal Unicode alphanumeric characters, or the underscore, or a hyphen character (allowed in the W3C recommendations). JAST is stricter than W3C, in that it excludes underscore as an identifier start, and excludes dot as an identifier part.

Parameters:

name - the name.

Throws:

SyntaxError - if the identifier is invalid.

setPrefix

private void setPrefix(java.lang.String prefix)
                throws SyntaxError

Secret method to validate XML prefix identifiers. The prefix must not be null, nor the empty string. It must start with a legal Unicode (letter) character and must continue with legal Unicode alphanumeric characters or the underscore. No other characters are allowed, in particular, hyphen and dot are illegal.

Parameters:

prefix - the prefix.

Throws:

SyntaxError - if the prefix is invalid.

getIdentifier

public java.lang.String getIdentifier()

Returns the identifier of this Markup content. The identifier is an interned symbol and may be compared with other identifiers using "==" for speed. If this Markup content has no prefix, the identifier is equivalent to the name. Otherwise, it is the concatenation of the symbols prefix + ":" + name.

Overrides:

getIdentifier in class Content

Returns:

the identifier.

getPrefix

public java.lang.String getPrefix()

Returns the prefix of this Markup content. The prefix is an interned symbol and may be compared with other prefixes using "==" for speed.

Returns:

the prefix, or null if none exists.

getName

public java.lang.String getName()

Returns the name of this Markup content. The name is an interned symbol and may be compared with other names using "==" for speed. The name is the short name of the Markup content, disregarding any prefix.

Returns:

the name.

getNamespace

public Namespace getNamespace()

Returns the namespace associated with this Markup. If this Markup has no prefix, searches up the parent Element tree for a default "xmlns" attribute. If this Markup has a prefix "abc", searches up the parent Element tree for an attribute named "xmlns:abc". If found, wraps the attribute in a Namespace. If no attribute is found, returns the empty Namespace, in which 'xmlns' maps to the empty string. Always returns a unique Namespace object for each namespace attribute.

Returns:

the Namespace associated with this Markup.