Class QName
- All Implemented Interfaces:
- Serializable
QName represents a qualified name
 as defined in the XML specifications: XML Schema Part2:
 Datatypes specification, Namespaces
 in XML.
 
The value of a QName contains a Namespace
 URI, local part and
 prefix.
The prefix is included in QName to retain lexical
 information when present in an XML input source. The prefix is
 NOT used in QName.equals(Object) or to compute the QName.hashCode().  Equality and the hash code are defined using
 only the Namespace URI and local part.
If not specified, the Namespace URI is set to XMLConstants.NULL_NS_URI.
 If not specified, the prefix is set to XMLConstants.DEFAULT_NS_PREFIX.
QName is immutable.
- Since:
- 1.5
- See Also:
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Constructor SummaryConstructorsConstructorDescriptionQNameconstructor specifying the local part.QNameconstructor specifying the Namespace URI and local part.QNameconstructor specifying the Namespace URI, local part and prefix.
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Method SummaryModifier and TypeMethodDescriptionfinal booleanTest thisQNamefor equality with anotherObject.Get the local part of thisQName.Get the Namespace URI of thisQName.Get the prefix of thisQName.final inthashCode()Generate the hash code for thisQName.toString()Stringrepresentation of thisQName.static QNameQNamederived from parsing the formattedString.
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Constructor Details- 
QNameQNameconstructor specifying the Namespace URI and local part.If the Namespace URI is null, it is set toXMLConstants.NULL_NS_URI. This value represents no explicitly defined Namespace as defined by the Namespaces in XML specification. This action preserves compatible behavior with QName 1.0. Explicitly providing theXMLConstants.NULL_NS_URIvalue is the preferred coding style.If the local part is nullanIllegalArgumentExceptionis thrown. A local part of "" is allowed to preserve compatible behavior with QName 1.0.When using this constructor, the prefix is set to XMLConstants.DEFAULT_NS_PREFIX.The Namespace URI is not validated as a URI reference. The local part is not validated as a NCName as specified in Namespaces in XML. - Parameters:
- namespaceURI- Namespace URI of the- QName
- localPart- local part of the- QName
- Throws:
- IllegalArgumentException- When- localPartis- null
- See Also:
 
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QNameQNameconstructor specifying the Namespace URI, local part and prefix.If the Namespace URI is null, it is set toXMLConstants.NULL_NS_URI. This value represents no explicitly defined Namespace as defined by the Namespaces in XML specification. This action preserves compatible behavior with QName 1.0. Explicitly providing theXMLConstants.NULL_NS_URIvalue is the preferred coding style.If the local part is nullanIllegalArgumentExceptionis thrown. A local part of "" is allowed to preserve compatible behavior with QName 1.0.If the prefix is null, anIllegalArgumentExceptionis thrown. UseXMLConstants.DEFAULT_NS_PREFIXto explicitly indicate that no prefix is present or the prefix is not relevant.The Namespace URI is not validated as a URI reference. The local part and prefix are not validated as a NCName as specified in Namespaces in XML. - Parameters:
- namespaceURI- Namespace URI of the- QName
- localPart- local part of the- QName
- prefix- prefix of the- QName
- Throws:
- IllegalArgumentException- When- localPartor- prefixis- null
 
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QNameQNameconstructor specifying the local part.If the local part is nullanIllegalArgumentExceptionis thrown. A local part of "" is allowed to preserve compatible behavior with QName 1.0.When using this constructor, the Namespace URI is set to XMLConstants.NULL_NS_URIand the prefix is set toXMLConstants.DEFAULT_NS_PREFIX.In an XML context, all Element and Attribute names exist in the context of a Namespace. Making this explicit during the construction of a QNamehelps prevent hard to diagnosis XML validity errors. The constructorsQName(String namespaceURI, String localPart)andQName(String namespaceURI, String localPart, String prefix)are preferred.The local part is not validated as a NCName as specified in Namespaces in XML. - Parameters:
- localPart- local part of the- QName
- Throws:
- IllegalArgumentException- When- localPartis- null
- See Also:
 
 
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Method Details- 
getNamespaceURIGet the Namespace URI of this QName.- Returns:
- Namespace URI of this QName
 
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getLocalPart
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getPrefixGet the prefix of this QName.The prefix assigned to a QNamemight NOT be valid in a different context. For example, aQNamemay be assigned a prefix in the context of parsing a document but that prefix may be invalid in the context of a different document.- Returns:
- prefix of this QName
 
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equalsTest this QNamefor equality with anotherObject.If the Objectto be tested is not aQNameor isnull, then this method returnsfalse.Two QNames are considered equal if and only if both the Namespace URI and local part are equal. This method usesString.equals()to check equality of the Namespace URI and local part. The prefix is NOT used to determine equality.This method satisfies the general contract of Object.equals(Object)
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hashCodepublic final int hashCode()Generate the hash code for this QName.The hash code is calculated using both the Namespace URI and the local part of the QName. The prefix is NOT used to calculate the hash code.This method satisfies the general contract of Object.hashCode().
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toStringStringrepresentation of thisQName.The commonly accepted way of representing a QNameas aStringwas defined by James Clark. Although this is not a standard specification, it is in common use, e.g.Transformer.setParameter(String name, Object value). This implementation represents aQNameas: "{" + Namespace URI + "}" + local part. If the Namespace URI.equals(XMLConstants.NULL_NS_URI), only the local part is returned. An appropriate use of this method is for debugging or logging for human consumption.Note the prefix value is NOT returned as part of the Stringrepresentation.This method satisfies the general contract of Object.toString().
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valueOfQNamederived from parsing the formattedString.If the Stringisnullor does not conform toQName.toString()formatting, anIllegalArgumentExceptionis thrown.The StringMUST be in the form returned byQName.toString().The commonly accepted way of representing a QNameas aStringwas defined by James Clark. Although this is not a standard specification, it is in common use, e.g.Transformer.setParameter(String name, Object value). This implementation parses aStringformatted as: "{" + Namespace URI + "}" + local part. If the Namespace URI.equals(XMLConstants.NULL_NS_URI), only the local part should be provided.The prefix value CANNOT be represented in the Stringand will be set toXMLConstants.DEFAULT_NS_PREFIX.This method does not do full validation of the resulting QName.The Namespace URI is not validated as a URI reference. The local part is not validated as a NCName as specified in Namespaces in XML. - Parameters:
- qNameAsString-- Stringrepresentation of the- QName
- Returns:
- QNamecorresponding to the given- String
- Throws:
- IllegalArgumentException- When- qNameAsStringis- nullor malformed
- See Also:
 
 
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