Package net.sf.saxon.sxpath

Class IndependentContext

java.lang.Object
net.sf.saxon.sxpath.AbstractStaticContext
net.sf.saxon.sxpath.IndependentContext
All Implemented Interfaces:
Serializable, SourceLocator, Container, StaticContext, NamespaceResolver, XPathStaticContext
public class IndependentContext extends AbstractStaticContext implements XPathStaticContext, NamespaceResolver, Serializable, Container
An IndependentContext provides a context for parsing an XPath expression appearing in a context other than a stylesheet.

This class is used in a number of places where freestanding XPath expressions occur. These include the native Saxon XPath API, the .NET XPath API, XPath expressions used in XML Schema identity constraints, and XPath expressions supplied to saxon:evaluate(). It is not used by the JAXP XPath API (though it shares code with that API through the common superclass AbstractStaticContext).

This class currently provides no mechanism for binding user-defined functions.

See Also:

  • Constructor Details

    • IndependentContext

      public IndependentContext()
      Create an IndependentContext along with a new (non-schema-aware) Saxon Configuration

    • IndependentContext

      public IndependentContext(Configuration config)
      Create an IndependentContext using a specific Configuration
      Parameters:
      config - the Saxon configuration to be used

  • Method Details

    • copy

      public IndependentContext copy()
      Create a copy of this IndependentContext. All aspects of the context are copied except for declared variables.
      Returns:
      the new copy

    • declareNamespace

      public void declareNamespace(String prefix, String uri)
      Declare a namespace whose prefix can be used in expressions
      Parameters:
      prefix - The namespace prefix. Must not be null. Supplying "" sets the default element namespace.
      uri - The namespace URI. Must not be null.

    • clearNamespaces

      public void clearNamespaces()
      Clear all the declared namespaces, except for the standard ones (xml, xslt, saxon, xdt). This also resets the default element namespace to the "null" namespace

    • clearAllNamespaces

      public void clearAllNamespaces()
      Clear all the declared namespaces, including the standard ones (xml, xslt, saxon). Leave only the XML namespace and the default namespace (xmlns=""). This also resets the default element namespace to the "null" namespace.

    • setNamespaces

      public void setNamespaces(NodeInfo node)
      Declares all the namespaces that are in-scope for a given node, removing all previous namespace declarations. In addition, the standard namespaces (xml, xslt, saxon) are declared. This method also sets the default element namespace to be the same as the default namespace for this node.
      Parameters:
      node - The node whose in-scope namespaces are to be used as the context namespaces. If the node is an attribute, text node, etc, then the namespaces of its parent element are used.

    • setNamespaceResolver

      public void setNamespaceResolver(NamespaceResolver resolver)
      Set an external namespace resolver. If this is set, then all resolution of namespace prefixes is delegated to the external namespace resolver, and namespaces declared individually on this IndependentContext object are ignored.
      Specified by:
      setNamespaceResolver in interface XPathStaticContext
      Parameters:
      resolver - the external NamespaceResolver

    • declareVariable

      public XPathVariable declareVariable(QNameValue qname)
      Declare a variable. A variable must be declared before an expression referring to it is compiled. The initial value of the variable will be the empty sequence
      Specified by:
      declareVariable in interface XPathStaticContext
      Parameters:
      qname - The name of the variable
      Returns:
      an XPathVariable object representing information about the variable that has been declared.

    • declareVariable

      public XPathVariable declareVariable(String namespaceURI, String localName)
      Declare a variable. A variable must be declared before an expression referring to it is compiled. The initial value of the variable will be the empty sequence
      Specified by:
      declareVariable in interface XPathStaticContext
      Parameters:
      namespaceURI - The namespace URI of the name of the variable. Supply "" to represent names in no namespace (null is also accepted)
      localName - The local part of the name of the variable (an NCName)
      Returns:
      an XPathVariable object representing information about the variable that has been declared.

    • getSlotNumber

      public int getSlotNumber(QNameValue qname)
      Get the slot number allocated to a particular variable
      Parameters:
      qname - the name of the variable
      Returns:
      the slot number, or -1 if the variable has not been declared

    • getURIForPrefix

      public String getURIForPrefix(String prefix) throws XPathException
      Get the URI for a prefix, using the declared namespaces as the context for namespace resolution. The default namespace is NOT used when the prefix is empty. This method is provided for use by the XPath parser.
      Specified by:
      getURIForPrefix in interface StaticContext
      Parameters:
      prefix - The prefix
      Returns:
      the corresponding namespace URI
      Throws:
      XPathException - if the prefix is not declared

    • getNamespaceResolver

      public NamespaceResolver getNamespaceResolver()
      Description copied from interface: StaticContext
      Get a namespace resolver to resolve the namespaces declared in this static context.
      Specified by:
      getNamespaceResolver in interface StaticContext
      Returns:
      a namespace resolver.

    • getURIForPrefix

      public String getURIForPrefix(String prefix, boolean useDefault)
      Get the namespace URI corresponding to a given prefix. Return null if the prefix is not in scope.
      Specified by:
      getURIForPrefix in interface NamespaceResolver
      Parameters:
      prefix - the namespace prefix
      useDefault - true if the default namespace is to be used when the prefix is ""
      Returns:
      the uri for the namespace, or null if the prefix is not in scope. Return "" if the prefix maps to the null namespace.

    • iteratePrefixes

      public Iterator iteratePrefixes()
      Get an iterator over all the prefixes declared in this namespace context. This will include the default namespace (prefix="") and the XML namespace where appropriate
      Specified by:
      iteratePrefixes in interface NamespaceResolver

    • bindVariable

      public VariableReference bindVariable(StructuredQName qName) throws XPathException
      Bind a variable used in an XPath Expression to the XSLVariable element in which it is declared. This method is provided for use by the XPath parser, and it should not be called by the user of the API, or overridden, unless variables are to be declared using a mechanism other than the declareVariable method of this class.
      Specified by:
      bindVariable in interface StaticContext
      Parameters:
      qName - the name of the variable
      Returns:
      the resulting variable reference
      Throws:
      XPathException

    • getStackFrameMap

      public SlotManager getStackFrameMap()
      Get a Stack Frame Map containing definitions of all the declared variables. This will return a newly created object that the caller is free to modify by adding additional variables, without affecting the static context itself.
      Specified by:
      getStackFrameMap in interface XPathStaticContext
      Returns:
      a SlotManager object holding details of the allocation of variables on the stack frame.

    • isImportedSchema

      public boolean isImportedSchema(String namespace)
      Description copied from interface: StaticContext
      Determine whether a Schema for a given target namespace has been imported. Note that the in-scope element declarations, attribute declarations and schema types are the types registered with the (schema-aware) configuration, provided that their namespace URI is registered in the static context as being an imported schema namespace. (A consequence of this is that within a Configuration, there can only be one schema for any given namespace, including the null namespace).
      Specified by:
      isImportedSchema in interface StaticContext
      Parameters:
      namespace - the target namespace in question
      Returns:
      true if the given namespace has been imported

    • getImportedSchemaNamespaces

      public Set getImportedSchemaNamespaces()
      Get the set of imported schemas
      Specified by:
      getImportedSchemaNamespaces in interface StaticContext
      Returns:
      a Set, the set of URIs representing the names of imported schemas

    • setImportedSchemaNamespaces

      public void setImportedSchemaNamespaces(Set namespaces)
      Register the set of imported schema namespaces
      Parameters:
      namespaces - the set of namespaces for which schema components are available in the static context