Package net.sf.saxon.expr.instruct

Class IterateInstr

    • Constructor Detail

      • IterateInstr

        public IterateInstr​(Expression select,
                    LocalParamBlock initiallyExp,
                    Expression action,
                    Expression onCompletion)
        Create an xsl:iterate instruction
        Parameters:
        select - the select expression
        initiallyExp - the initialization of the xsl:param elements
        action - the body of the xsl:iterate loop
        onCompletion - the expression to be evaluated before final completion, may be null

    • Method Detail

      • setSelect

        public void setSelect​(Expression select)

      • setInitiallyExp

        public void setInitiallyExp​(LocalParamBlock initiallyExp)

      • setAction

        public void setAction​(Expression action)

      • getOnCompletion

        public Expression getOnCompletion()

      • setOnCompletion

        public void setOnCompletion​(Expression onCompletion)

      • operands

        public java.lang.Iterable<Operand> operands()
        Description copied from class: Expression
        Get the immediate sub-expressions of this expression, with information about the relationship of each expression to its parent expression.

        If the expression is a Callable, then it is required that the order of the operands returned by this function is the same as the order of arguments supplied to the corresponding call() method.

        Specified by:
        operands in class Instruction
        Returns:
        an iterator containing the sub-expressions of this expression

      • getInstructionNameCode

        public int getInstructionNameCode()
        Get the namecode of the instruction for use in diagnostics
        Overrides:
        getInstructionNameCode in class Instruction
        Returns:
        a code identifying the instruction: typically but not always the fingerprint of a name in the XSLT namespace

      • typeCheck

        public Expression typeCheck​(ExpressionVisitor visitor,
                            ContextItemStaticInfo contextInfo)
                     throws XPathException
        Type-check the expression
        Overrides:
        typeCheck in class Expression
        Parameters:
        visitor - an expression visitor
        contextInfo - Information available statically about the context item: whether it is (possibly) absent; its static type; its streaming posture.
        Returns:
        the original expression, rewritten to perform necessary run-time type checks, and to perform other type-related optimizations
        Throws:
        XPathException - if an error is discovered during this phase (typically a type error)

      • optimize

        public Expression optimize​(ExpressionVisitor visitor,
                           ContextItemStaticInfo contextInfo)
                    throws XPathException
        Description copied from class: Expression
        Perform optimisation of an expression and its subexpressions. This is the third and final phase of static optimization.

        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 Expression
        Parameters:
        visitor - an expression visitor
        contextInfo - 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)

      • isCompilable

        public boolean isCompilable()
        Test whether it is possible to generate byte-code for the instruction. This is not possible unless any xsl:break or xsl:next-iteration instructions are part of the same compilation unit, which is not the case if they appear within a try-catch.
        Returns:
        true if the instruction does not contain an xsl:break or xsl:next-iteration instruction within a try/catch block

      • getItemType

        public final ItemType getItemType()
        Determine the data type of the items returned by this expression
        Overrides:
        getItemType in class Instruction
        Returns:
        the data type

      • mayCreateNewNodes

        public final boolean mayCreateNewNodes()
        Determine whether this instruction creates new nodes. This implementation returns true if the "action" creates new nodes. (Nodes created by the condition can't contribute to the result).
        Overrides:
        mayCreateNewNodes in class Instruction
        Returns:
        true if the instruction creates new nodes under some input conditions (or if it can't be proved that it doesn't)

      • hasVariableBinding

        public boolean hasVariableBinding​(Binding binding)
        Ask whether this expression is, or contains, the binding of a given variable
        Overrides:
        hasVariableBinding in class Expression
        Parameters:
        binding - the variable binding
        Returns:
        true if this expression is the variable binding (for example a ForExpression or LetExpression) or if it is a FLWOR expression that binds the variable in one of its clauses.

      • getStreamerName

        public java.lang.String getStreamerName()
        Get the (partial) name of a class that supports streaming of this kind of expression
        Overrides:
        getStreamerName in class Expression
        Returns:
        the partial name of a class that can be instantiated to provide streaming support in Saxon-EE, or null if there is no such class

      • checkPermittedContents

        public void checkPermittedContents​(SchemaType parentType,
                                   boolean whole)
                            throws XPathException
        Check that any elements and attributes constructed or returned by this expression are acceptable in the content model of a given complex type. It's always OK to say yes, since the check will be repeated at run-time. The process of checking element and attribute constructors against the content model of a complex type also registers the type of content expected of those constructors, so the static validation can continue recursively.
        Overrides:
        checkPermittedContents in class Expression
        Parameters:
        parentType - the "given complex type": the method is checking that the nodes returned by this expression are acceptable members of the content model of this type
        whole - if true, we want to check that the value of this expression satisfies the content model as a whole; if false we want to check that the value of the expression is acceptable as one part of the content
        Throws:
        XPathException - if the value delivered by this expression cannot be part of the content model of the given type

      • copy

        public Expression copy​(RebindingMap rebindings)
        Copy an expression. This makes a deep copy.
        Specified by:
        copy in class Expression
        Parameters:
        rebindings - a mutable list of (old binding, new binding) pairs that is used to update the bindings held in any local variable references that are copied.
        Returns:
        the copy of the original expression

      • export

        public void export​(ExpressionPresenter out)
            throws XPathException
        Diagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.
        Specified by:
        export in interface ExportAgent
        Specified by:
        export in class Expression
        Parameters:
        out - the expression presenter used to display the structure
        Throws:
        XPathException - if the export fails, for example if an expression is found that won't work in the target environment.