Class Variable

java.lang.Object
net.sf.saxon.trans.Variable
All Implemented Interfaces:
Serializable, Binding, VariableDeclaration

public final class Variable extends Object implements VariableDeclaration, Binding, Serializable
An object representing an XPath variable for use in the standalone XPath API. The object can only be created by calling the declareVariable method of class StandaloneContext.
See Also:
  • Method Details

    • make

      public static Variable make(QNameValue name, Configuration config)
      Factory method, for use by the declareVariable method of class StandaloneContext
    • setUseStack

      public void setUseStack(boolean useStack)
      Indicate that values of variables are to be found on the stack, not in the Variable object itself
    • isGlobal

      public boolean isGlobal()
      Indicate whether the binding is local or global. A global binding is one that has a fixed value for the life of a query or transformation; any other binding is local.
      Specified by:
      isGlobal in interface Binding
    • isAssignable

      public final boolean isAssignable()
      Test whether it is permitted to assign to the variable using the saxon:assign extension element. This will only be for an XSLT global variable where the extra attribute saxon:assignable="yes" is present.
      Specified by:
      isAssignable in interface Binding
    • setSlotNumber

      public void setSlotNumber(int slotNumber)
      Set the slot number allocated to this variable
      Parameters:
      slotNumber -
    • getLocalSlotNumber

      public int getLocalSlotNumber()
      If this is a local variable held on the local stack frame, return the corresponding slot number. In other cases, return -1.
      Specified by:
      getLocalSlotNumber in interface Binding
    • getVariableName

      public String getVariableName()
      Get the name of the variable. Used for diagnostic purposes only.
      Specified by:
      getVariableName in interface VariableDeclaration
      Returns:
      the name of the variable, as a string (containing the raw QName)
    • getNameCode

      public int getNameCode()
      Establish the nameCode of the name of this variable.
      Specified by:
      getNameCode in interface VariableDeclaration
      Returns:
      the nameCode
    • setValue

      public void setValue(Object value) throws XPathException
      Assign a value to the variable. This value may be changed between successive evaluations of a compiled XPath expression that references the variable. If this method is called, the value will be set directly within the Variable object. This is only workable if compilation and execution happen in the same thread. The preferred approach is to set the variable in the stack frame of the XPathContext object.
      Parameters:
      value - the value of the variable, as a Java object. This is converted to the "best fit" XPath data type.
      Throws:
      XPathException - if the Java value cannot be converted to an XPath type
    • setXPathValue

      public void setXPathValue(ValueRepresentation value)
      Assign a value to the variable. This value may be changed between successive evaluations of a compiled XPath expression that references the variable. If this method is called, the value will be set directly within the Variable object. This is only workable if compilation and execution happen in the same thread. The preferred approach is to set the variable in the stack frame of the XPathContext object.
      Parameters:
      value - the value of the variable, which must be an instance of a class representing a value in the XPath model.
    • registerReference

      public void registerReference(BindingReference ref)
      Method called by the XPath expression parser to register a reference to this variable. This method should not be called by users of the API.
      Specified by:
      registerReference in interface VariableDeclaration
    • evaluateVariable

      public ValueRepresentation evaluateVariable(XPathContext context)
      Get the value of the variable. This method is used by the XPath execution engine to retrieve the value.
      Specified by:
      evaluateVariable in interface Binding
      Parameters:
      context - The dynamic evaluation context
      Returns:
      The value of the variable