uk.ac.sheffield.jast.valid

Class TextContentRule

java.lang.Object

uk.ac.sheffield.jast.valid.GrammarRule

uk.ac.sheffield.jast.valid.SimpleRule

uk.ac.sheffield.jast.valid.TextContentRule

public class TextContentRule
extends SimpleRule

TextContentRule is a GrammarRule that accepts Elements with text content. A TextContentRule accepts Elements that have only textual content and no other Element children. Legal textual content includes both PCDATA and CDATA (though DTDs only specify '#PCDATA' in XML 1.0) Since text may also include the empty String, this TextContentRule succeeds if the Element is empty. If a Filter restriction is added, this is also applied to any text found under the Element.

A TextContentRule is created for each PCDATA term found in a DTD grammar rule production. A TextContentRule is created for the XSD simple type xs:simpleType.

Version:

2.5

Author:

Anthony J H Simons

Field Summary

Fields

Modifier and Type	Field and Description
private static Filter	textFilter The TextFilter used by this TextContentRule.
private Filter	valueFilter The ValueFilter used by this TextContentRule.

Fields inherited from class uk.ac.sheffield.jast.valid.GrammarRule

identifier, parent

Constructor Summary

Constructors

Constructor and Description
TextContentRule() Creates a TextContentRule testing for the exclusive presence of textual content.

Method Summary

Modifier and Type	Method and Description
boolean	accept(Element node) Reports whether this TextContentRule accepts a given Element node, having textual content.
void	restrict(Filter filter) Restricts this TextContentRule by adding a further Filter.
java.lang.String	toString() Returns a pretty representation of this TextContentRule.

Methods inherited from class uk.ac.sheffield.jast.valid.SimpleRule

isNestingRule

Methods inherited from class uk.ac.sheffield.jast.valid.GrammarRule

addChildRule, clearError, getChildIndex, getIdentifier, getRuleChildren, isAttributeRule, isElementRule, setChildIndex, setError, setParent, validate

Methods inherited from class java.lang.Object

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

Field Detail

textFilter

private static Filter textFilter

The TextFilter used by this TextContentRule. This is used to filter the contents of an Element to determine that at least some textual content is present.

valueFilter

private Filter valueFilter

The ValueFilter used by this TextContentRule. This is initially set to a NodeFilter accepting any Element, but may be further restricted to accept Elements with specific kinds of textual content.

Constructor Detail

TextContentRule

public TextContentRule()

Creates a TextContentRule testing for the exclusive presence of textual content. The identifier of a TextContentRule is the symbol "PCDATA". Installs default filters accepting any kind of textual content.

Method Detail

accept

public boolean accept(Element node)

Reports whether this TextContentRule accepts a given Element node, having textual content. If the node has further Element children (which is disallowed for text-only grammar rule productions), returns false immediately and reports a mismatch. Otherwise, if the node has no textual content, or unsuitable textual content, returns false and reports a mismatch; otherwise returns true.

Overrides:

accept in class GrammarRule

Parameters:

node - an Element.

Returns:

true, if the node contains suitable textual content.

restrict

public void restrict(Filter filter)

Restricts this TextContentRule by adding a further Filter. The kind of restriction depends on the kind of Filter that is added. A ValueFilter will accept elements having a specific value; while a RangeFilter will accept elements having one from a range of values; and a TypeFilter will accept elements having a value of a given type. Replaces the current valueFilter by the logical conjunction of the current valueFilter and the new filter.

Overrides:

restrict in class GrammarRule

Parameters:

filter - the extra restriction to apply.

toString

public java.lang.String toString()

Returns a pretty representation of this TextContentRule. Returns the distinguished symbol "$TextContent".

Overrides:

toString in class java.lang.Object