Package org.loboevolution.apache.xpath.operations

Class Operation

java.lang.Object
org.loboevolution.apache.xpath.Expression
org.loboevolution.apache.xpath.operations.Operation
All Implemented Interfaces:
SourceLocator, ExpressionNode, XPathVisitable
Direct Known Subclasses:
And, Div, Equals, Gt, Gte, Lt, Lte, Minus, Mod, Mult, NotEquals, Or, Plus
public class Operation extends Expression
The baseclass for a binary operation.

  • Field Details

    • m_left

      protected Expression m_left
      The left operand expression.

    • m_right

      protected Expression m_right
      The right operand expression.

  • Constructor Details

    • Operation

      public Operation()

  • Method Details

    • canTraverseOutsideSubtree

      public boolean canTraverseOutsideSubtree()
      Tell if this expression or it's subexpressions can traverse outside the current subtree.
      Overrides:
      canTraverseOutsideSubtree in class Expression
      Returns:
      true if traversal outside the context node's subtree can occur.

    • setLeftRight

      public void setLeftRight(Expression l, Expression r)
      Set the left and right operand expressions for this operation.
      Parameters:
      l - The left expression operand.
      r - The right expression operand.

    • execute

      public XObject execute(XPathContext xctxt) throws TransformerException
      Execute an expression in the XPath runtime context, and return the result of the expression.
      Specified by:
      execute in class Expression
      Parameters:
      xctxt - The XPath runtime context.
      Returns:
      The result of the expression in the form of a XObject.
      Throws:
      TransformerException - if a runtime exception occurs.

    • operate

      public XObject operate(XObject left, XObject right) throws TransformerException
      Apply the operation to two operands, and return the result.
      Parameters:
      left - non-null reference to the evaluated left operand.
      right - non-null reference to the evaluated right operand.
      Returns:
      non-null reference to the XObject that represents the result of the operation.
      Throws:
      TransformerException - in case of error

    • callVisitors

      public void callVisitors(XPathVisitor visitor)
      This will traverse the hierarchy, calling the visitor for each member. If the called visitor method returns false, the subtree should not be called.
      Parameters:
      visitor - The visitor whose appropriate method will be called.

    • deepEquals

      public boolean deepEquals(Expression expr)
      Compare this object with another object and see if they are equal, include the sub heararchy.
      Specified by:
      deepEquals in class Expression
      Parameters:
      expr - Another expression object.
      Returns:
      true if this objects class and the expr object's class are the same, and the data contained within both objects are considered equal.