Class StringJoin

    • Constructor Detail

      • StringJoin

        public StringJoin()
    • Method Detail

      • setReturnEmptyIfEmpty

        public void setReturnEmptyIfEmpty​(boolean option)
        Indicate that when the input sequence (first argument) is empty, the function should return an empty sequence rather than an empty string
        Parameters:
        option - true if an empty sequence should be returned when the input is an empty sequence.
      • isReturnEmptyIfEmpty

        public boolean isReturnEmptyIfEmpty()
      • copy

        public Expression copy()
        Description copied from class: SystemFunction
        Copy an expression. This makes a deep copy.
        Overrides:
        copy in class SystemFunction
        Returns:
        the copy of the original expression
      • equals

        public boolean equals​(java.lang.Object o)
        Determine whether two expressions are equivalent
        Overrides:
        equals in class SystemFunction
      • optimize

        public Expression optimize​(ExpressionVisitor visitor,
                                   ExpressionVisitor.ContextItemType contextItemType)
                            throws XPathException
        Description copied from class: SystemFunction
        Perform optimisation of an expression and its subexpressions.

        This method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.

        Overrides:
        optimize in class SystemFunction
        Parameters:
        visitor - an expression visitor
        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 original expression, rewritten if appropriate to optimize execution
        Throws:
        XPathException - if an error is discovered during this phase (typically a type error)
      • evaluateItem

        public Item evaluateItem​(XPathContext c)
                          throws XPathException
        Description copied from class: Expression
        Evaluate an expression as a single item. This always returns either a single Item or null (denoting the empty sequence). No conversion is done. This method should not be used unless the static type of the expression is a subtype of "item" or "item?": that is, it should not be called if the expression may return a sequence. There is no guarantee that this condition will be detected.
        Overrides:
        evaluateItem in class Expression
        Parameters:
        c - The context in which the expression is to be evaluated
        Returns:
        the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
        Throws:
        XPathException - if any dynamic error occurs evaluating the expression
      • process

        public void process​(XPathContext context)
                     throws XPathException
        Process the instruction in push mode. This avoids constructing the concatenated string in memory, instead its parts can be sent straight to the serializer.
        Overrides:
        process in class Expression
        Parameters:
        context - The dynamic context, giving access to the current node, the current variables, etc.
        Throws:
        XPathException - if a dynamic error occurs