Class ContextSupport

java.lang.Object
com.werken.xpath.ContextSupport

public class ContextSupport extends Object

ContextSupport maintains information to aid in the execution of the XPath against a context node.

It separates the knowledge of functions, variables and namespace-bindings from the context node to be walked.

Author:
bob mcwhirter (bob @ werken.com)
  • Constructor Details

    • ContextSupport

      public ContextSupport()
      Construct a semantically empty ContextSupport
    • ContextSupport

      public ContextSupport(NamespaceContext nsContext, FunctionContext functionContext, VariableContext variableContext)
      Construct a semantically initialized ContextSupport
      Parameters:
      nsContext - The NamespaceContext implementation
      functionContext - The FunctionContext implementation
      variableContext - The VariableContext implementation
  • Method Details

    • setNamespaceContext

      public void setNamespaceContext(NamespaceContext nsContext)
      Set the NamespaceContext implementation
      Parameters:
      nsContext - The NamespaceContext implementation
    • setFunctionContext

      public void setFunctionContext(FunctionContext functionContext)
      Set the FunctionContext implementation
      Parameters:
      functionContext - The FunctionContext implementation
    • setVariableContext

      public void setVariableContext(VariableContext variableContext)
      Set the VariableContext implementation
      Parameters:
      variableContext - The FunctionContext implementation
    • translateNamespacePrefix

      public String translateNamespacePrefix(String prefix)
      Translate a namespace prefix into a URI

      Using the NamespaceContext implementation, translate the prefix used in a component of an XPath into its expanded namespace URI.

      Parameters:
      prefix - The namespace prefix
      Returns:
      The URI matching the prefix
      See Also:
    • getFunction

      public Function getFunction(String name)
      Retrieve a named function

      Retrieve the named function object, or null if no such function exists. Delegates to the FunctionContext implementation provided, if any.

      Parameters:
      name - The name of the function sought.
      Returns:
      The Function matching the specified name.
      See Also:
    • getVariableValue

      public Object getVariableValue(String name)
      Resolve a variable binding

      Retrieve the currently bound value of the named variable, or null if no such binding exists. Delegates to the VariableContext implementation provided, if any.

      Parameters:
      name - The name of the variable sought.
      Returns:
      The currently bound value of the variable, or null.
      See Also: