Package net.sf.saxon.pattern

Class BasePatternWithPredicate

    • Constructor Detail

      • BasePatternWithPredicate

        public BasePatternWithPredicate​(Pattern basePattern,
                                Expression predicate)

    • Method Detail

      • getBasePattern

        public Pattern getBasePattern()

      • bindCurrent

        public void bindCurrent​(LocalBinding binding)
        Replace any calls on current() by a variable reference bound to the supplied binding
        Overrides:
        bindCurrent in class Pattern

      • matchesCurrentGroup

        public boolean matchesCurrentGroup()
        Ask whether the pattern is anchored on a call on current-group()
        Overrides:
        matchesCurrentGroup in class Pattern
        Returns:
        true if calls on matchesBeneathAnchor should test with all nodes in the current group as anchor nodes. If false, only the first node in a group is treated as the anchor node

      • operands

        public java.lang.Iterable<Operand> operands()
        Get the immediate sub-expressions of this expression, with information about the relationship of each expression to its parent expression. Default implementation works off the results of iterateSubExpressions()

        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.

        Overrides:
        operands in class Expression
        Returns:
        an iterator containing the sub-expressions of this expression

      • allocateSlots

        public int allocateSlots​(SlotManager slotManager,
                         int nextFree)
        Allocate slots to any variables used within the pattern
        Overrides:
        allocateSlots in class Pattern
        Parameters:
        slotManager - holds details of the allocated slots
        nextFree - the next slot that is free to be allocated @return the next slot that is free to be allocated
        Returns:
        the next slot that is free to be allocated

      • matches

        public boolean matches​(Item item,
                       XPathContext context)
                throws XPathException
        Determine whether this Pattern matches the given Node.
        Specified by:
        matches in class Pattern
        Parameters:
        item - The NodeInfo representing the Element or other node to be tested against the Pattern
        context - The dynamic context. Only relevant if the pattern uses variables, or contains calls on functions such as document() or key().
        Returns:
        true if the node matches the Pattern, false otherwise
        Throws:
        XPathException - if an error occurs while matching the pattern (the caller will usually treat this the same as a false result)

      • matchesBeneathAnchor

        public boolean matchesBeneathAnchor​(NodeInfo node,
                                    NodeInfo anchor,
                                    XPathContext context)
                             throws XPathException
        Description copied from class: Pattern
        Determine whether this pattern matches a given Node within the subtree rooted at a given anchor node. This method is used when the pattern is used for streaming.
        Overrides:
        matchesBeneathAnchor in class Pattern
        Parameters:
        node - The NodeInfo representing the Element or other node to be tested against the Pattern
        anchor - The anchor node, which must match any AnchorPattern subpattern
        context - The dynamic context. Only relevant if the pattern uses variables, or contains calls on functions such as document() or key().
        Returns:
        true if the node matches the Pattern, false otherwise
        Throws:
        XPathException - if an error occurs while matching the pattern (the caller will usually treat this the same as a false result)

      • getUType

        public UType getUType()
        Get a UType indicating which kinds of items this Pattern can match.
        Specified by:
        getUType in class Pattern
        Returns:
        a UType indicating all the primitive types of item that the pattern can match.

      • getFingerprint

        public int getFingerprint()
        Determine the name fingerprint of nodes to which this pattern applies. Used for optimisation.
        Overrides:
        getFingerprint in class Pattern
        Returns:
        A fingerprint that the nodes must match, or -1 if it can match multiple fingerprints, or it if matches atomic values

      • getItemType

        public ItemType getItemType()
        Get an ItemType that all the items matching this pattern must satisfy
        Specified by:
        getItemType in class Pattern
        Returns:
        an ItemType, as specific as possible, which all the matching items satisfy

      • getDependencies

        public int getDependencies()
        Get the dependencies of the pattern. The only possible dependency for a pattern is on local variables. This is analyzed in those patterns where local variables may appear.
        Overrides:
        getDependencies in class Pattern
        Returns:
        the dependencies, as a bit-significant mask

      • typeCheck

        public Pattern typeCheck​(ExpressionVisitor visitor,
                         ContextItemStaticInfo contextItemType)
                  throws XPathException
        Type-check the pattern.
        Overrides:
        typeCheck in class Pattern
        Parameters:
        visitor - the expression visitor
        contextItemType - the type of the context item at the point where the pattern is defined. Set to null if it is known that the context item is undefined.
        Returns:
        the optimised Pattern
        Throws:
        XPathException - if an error is discovered during this phase (typically a type error)

      • optimize

        public Pattern optimize​(ExpressionVisitor visitor,
                        ContextItemStaticInfo contextInfo)
                 throws XPathException
        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 Pattern
        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)

      • convertToTypedPattern

        public Pattern convertToTypedPattern​(java.lang.String val)
                              throws XPathException
        Convert the pattern to a typed pattern, in which an element name is treated as schema-element(N)
        Overrides:
        convertToTypedPattern in class Pattern
        Parameters:
        val - either "strict" or "lax" depending on the value of xsl:mode/@typed
        Returns:
        either the original pattern unchanged, or a new pattern as the result of the conversion
        Throws:
        XPathException - if the pattern cannot be converted

      • isMotionless

        public boolean isMotionless()
        Description copied from class: Pattern
        Test whether a pattern is motionless, that is, whether it can be evaluated against a node without repositioning the input stream. This is a necessary condition for patterns used as the match pattern of a streamed template rule.
        Overrides:
        isMotionless in class Pattern
        Returns:
        true if the pattern is motionless, that is, if it can be evaluated against a streamed node without changing the position in the streamed input file

      • reconstruct

        public java.lang.String reconstruct()
        Display the pattern for diagnostics
        Overrides:
        reconstruct in class Pattern

      • toShortString

        public java.lang.String toShortString()
        Description copied from class: Expression
        Produce a short string identifying the expression for use in error messages
        Overrides:
        toShortString in class Pattern
        Returns:
        a short string, sufficient to identify the expression

      • copy

        public Pattern copy​(RebindingMap rebindings)
        Copy a pattern. This makes a deep copy.
        Specified by:
        copy in class Pattern
        Parameters:
        rebindings - variables that need to be re-bound
        Returns:
        the copy of the original pattern

      • equals

        public boolean equals​(java.lang.Object obj)
        Description copied from class: Expression
        The equals() test for expressions returns true if it can be determined that two expressions (given their static context) will return the same result in all circumstances. The value false is returned if this is not the case or if it cannot be determined to be the case.

        During the various phases of compilation, expression objects are mutable. Changing an expression may change its hashCode, and may change the result of equals() comparisons. Expressions should therefore not be held in data structures such as maps and sets that depend on equality comparison unless they are no longer subject to such mutation.

        Overrides:
        equals in class Expression
        Parameters:
        obj - the other operand; the result is false if this is not an Expression
        Returns:
        true if the other operand is an expression and if it can be determined that the two expressions are equivalent, in the sense that they will always return the same result.

      • computeHashCode

        protected int computeHashCode()
        Description copied from class: Expression
        Compute a hash code, which will then be cached for later use
        Overrides:
        computeHashCode in class Expression
        Returns:
        a computed hash code

      • export

        public void export​(ExpressionPresenter presenter)
            throws XPathException
        Description copied from class: Expression
        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 Pattern
        Parameters:
        presenter - 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.