Java in a Nutshell, 5th Edition [Electronic resources]

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Attributesorg.xml.sax

Java 1.4

This interface represents a list of attributes of an XML element and includes information about the attribute names, types, and values. If the SAX parser has read a DTD or schema for the document, this list of attributes will include attributes that are not explicitly specified in the document but which have a default value specified in the DTD or schema.

The most commonly used method is getValue( ) which returns the value of a named attribute (there is also a version of this method that returns the value of a numbered attribute; it is discussed later). If the SAX parser is not processing namespaces, you can use the one-argument version of getValue( ). Otherwise, use the two argument version to specify the URI that uniquely identifies the namespace, and the "local name" of the desired attribute within that namespace . The getType( ) methods are similar, except that they return the type of the named attribute, rather than its value. Note that getType( ) can only return useful information if the parser has read a DTD or schema for the document and knows the type of each attribute.

In XML documents the attributes of a tag can appear in any order. Attributes objects make no attempt to preserve the document source order of the tags. Nevertheless, it does impose an ordering on the attributes so that you can loop through them. getLength( ) returns the number of elements in the list. There are versions of getValue( ) and getType( ) that return the value and type of the attribute at a specified position in the list. You can also query the name of the attribute at a specified position, although the way you do this depends on whether the parser handles namespaces or not. If it does not process namespaces, use getQName( ) to get the name at a specified position. Otherwise, use getURI( ) and getLocalName( ) to obtain the URI and local name pair for the numbered attribute. Note that getQName( ) may return the empty string when namespace processing is on, and getLocalName( ) may return the empty string if namespace processing is off.

public interface

Attributes { // Public Instance Methods int

getIndex (String

qName ); int

getIndex (String

uri , String

localName ); int

getLength ( ); String

getLocalName (int

index ); String

getQName (int

index ); String

getType (String

qName ); String

getType (int

index ); String

getType (String

uri , String

localName ); String

getURI (int

index ); String

getValue (String

qName ); String

getValue (int

index ); String

getValue (String

uri , String

localName ); }

Implementations

org.xml.sax.ext.Attributes2, org.xml.sax.helpers.AttributesImpl

Passed To

org.xml.sax.ContentHandler.startElement( ), org.xml.sax.ext.Attributes2Impl.{Attributes2Impl( ), setAttributes( )}, org.xml.sax.helpers.AttributesImpl.{AttributesImpl( ), setAttributes( )}, org.xml.sax.helpers.DefaultHandler.startElement( ), org.xml.sax.helpers.XMLFilterImpl.startElement( ), org.xml.sax.helpers.XMLReaderAdapter.startElement( )