Class GeneralComparison10

  • All Implemented Interfaces:
    java.io.Serializable, javax.xml.transform.SourceLocator, Container, Expression, InstructionInfoProvider

    public class GeneralComparison10
    extends BinaryExpression
    GeneralComparison10: a boolean expression that compares two expressions for equals, not-equals, greater-than or less-than. This implements the operators =, !=, <, >, etc. This version of the class implements general comparisons in XPath 1.0 backwards compatibility mode, as defined in the Oct 2004 revision of the specifications.
    See Also:
    Serialized Form
    • Field Detail

      • singletonOperator

        protected int singletonOperator
    • Constructor Detail

      • GeneralComparison10

        public GeneralComparison10​(Expression p0,
                                   int op,
                                   Expression p1)
        Create a general comparison identifying the two operands and the operator
        Parameters:
        p0 - the left-hand operand
        op - the operator, as a token returned by the Tokenizer (e.g. Token.LT)
        p1 - the right-hand operand
    • Method Detail

      • typeCheck

        public Expression typeCheck​(StaticContext env,
                                    ItemType contextItemType)
                             throws XPathException
        Type-check the expression
        Specified by:
        typeCheck in interface Expression
        Overrides:
        typeCheck in class BinaryExpression
        Parameters:
        env - the static context of the expression
        contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
        Returns:
        the checked expression
        Throws:
        StaticError - if an error is discovered during this phase (typically a type error)
        XPathException
      • optimize

        public Expression optimize​(Optimizer opt,
                                   StaticContext env,
                                   ItemType contextItemType)
                            throws XPathException
        Optimize the expression
        Specified by:
        optimize in interface Expression
        Overrides:
        optimize in class BinaryExpression
        Parameters:
        opt - the optimizer in use. This provides access to supporting functions; it also allows different optimization strategies to be used in different circumstances.
        env - the static context of the expression
        contextItemType - the static type of "." at the point where this expression is invoked. The parameter is set to null if it is known statically that the context item will be undefined. If the type of the context item is not known statically, the argument is set to Type.ITEM_TYPE
        Returns:
        the checked expression
        Throws:
        net.sf.saxon.trans.StaticError - if an error is discovered during this phase (typically a type error)
        XPathException
      • getItemType

        public ItemType getItemType​(TypeHierarchy th)
        Determine the data type of the expression
        Parameters:
        th -
        Returns:
        Type.BOOLEAN