Package net.sf.saxon.expr

Class XPathContextMajor

  • All Implemented Interfaces:
    XPathContext
    public class XPathContextMajor
extends XPathContextMinor
    This class represents a "major context" in which an XPath expression is evaluated: a "major context" object allows all aspects of the dynamic context to change, whereas a "minor context" only allows changes to the focus and the destination for push output.

    • Constructor Detail

      • XPathContextMajor

        public XPathContextMajor​(Controller controller)
        Constructor should only be called by the Controller, which acts as a XPathContext factory.
        Parameters:
        controller - the Controller

      • XPathContextMajor

        public XPathContextMajor​(Item item,
                         Executable exec)
        Constructor for use in free-standing Java applications.
        Parameters:
        item - the item to use as the initial context item. If this is null, the comtext item is initially undefined (which will cause a dynamic error if it is referenced).
        exec - the Executable

    • Method Detail

      • newContext

        public XPathContextMajor newContext()
        Construct a new context as a copy of another. The new context is effectively added to the top of a stack, and contains a pointer to the previous context.
        Specified by:
        newContext in interface XPathContext
        Overrides:
        newContext in class XPathContextMinor
        Returns:
        a new context, created as a copy of this context

      • newContext

        public static XPathContextMajor newContext​(XPathContextMinor prev)
        Create a new "major" context (one that is capable of holding a stack frame with local variables
        Parameters:
        prev - the previous context (the one causing the new context to be created)
        Returns:
        the new major context

      • newThreadContext

        public static XPathContextMajor newThreadContext​(XPathContextMinor prev)
        Make a copy of the supplied context for use in a new thread (typically for an asynchronous xsl:result-document)
        Parameters:
        prev - the context to be copied
        Returns:
        the copy of the context

      • createThreadManager

        public void createThreadManager()
        Create a new thread manager. This is called when starting an XSLT Transformation, and also when entering a try/catch block. In Saxon-HE it does nothing.

      • waitForChildThreads

        public void waitForChildThreads()
                         throws XPathException
        Wait for child threads started under the control of this context to finish. This is called at the end of the (main thread of a) transformation, and also at the end of the "try" part of a try/catch. The threads affected are those used to implement xsl:result-document instructions.
        Specified by:
        waitForChildThreads in interface XPathContext
        Overrides:
        waitForChildThreads in class XPathContextMinor
        Throws:
        XPathException - if any of the child threads have failed with a dynamic error.

      • setLocalParameters

        public void setLocalParameters​(ParameterSet localParameters)
        Set the local parameters for the current template call.
        Parameters:
        localParameters - the supplied parameters

      • setTunnelParameters

        public void setTunnelParameters​(ParameterSet tunnelParameters)
        Set the tunnel parameters for the current template call.
        Parameters:
        tunnelParameters - the supplied tunnel parameters

      • setOrigin

        public void setOrigin​(ContextOriginator expr)
        Set the creating expression (for use in diagnostics). The origin is generally set to "this" by the object that creates the new context. It's up to the debugger to determine whether this information is useful. The object will either be an Expression, allowing information about the calling instruction to be obtained, or null.

      • getOrigin

        public ContextOriginator getOrigin()
        Get information about the creating expression or other construct.

      • setStackFrame

        public void setStackFrame​(SlotManager map,
                          Sequence[] variables)
        Set the local stack frame. This method is used when creating a Closure to support delayed evaluation of expressions. The "stack frame" is actually on the Java heap, which means it can survive function returns and the like.
        Parameters:
        map - the SlotManager, which holds static details of the allocation of variables to slots
        variables - the array of "slots" to hold the actual variable values. This array will be copied if it is too small to hold all the variables defined in the SlotManager

      • resetStackFrameMap

        public void resetStackFrameMap​(SlotManager map,
                               int numberOfParams)
        Reset the stack frame variable map, while reusing the StackFrame object itself. This is done on a tail call to a different function
        Parameters:
        map - the SlotManager representing the stack frame contents
        numberOfParams - the number of parameters required on the new stack frame

      • getAllVariableValues

        public Sequence[] getAllVariableValues()
        Get a all the variables in the stack frame
        Returns:
        an array holding all the variables, each referenceable by its slot number

      • resetAllVariableValues

        public void resetAllVariableValues​(Sequence[] values)
        Overwrite all the variables in the stack frame
        Parameters:
        values - an array holding all the variables, each referenceable by its slot number; the caller must ensure this is the correct length (and valid in other ways)

      • resetParameterValues

        public void resetParameterValues​(Sequence[] values)
        Overwrite all the parameters in the stack frame. (Used from compiled bytecode)
        Parameters:
        values - an array holding all the parameters, each referenceable by its slot number; the caller must ensure this is the correct length (and valid in other ways)

      • requestTailCall

        public void requestTailCall​(TailCallLoop.TailCallInfo targetFn,
                            Sequence[] variables)
        Reset the local stack frame. This method is used when processing a tail-recursive function. Instead of the function being called recursively, the parameters are set to new values and the function body is evaluated repeatedly
        Parameters:
        targetFn - the user function being called using tail recursion
        variables - the parameter to be supplied to the user function

      • getTailCallInfo

        public TailCallLoop.TailCallInfo getTailCallInfo()
        Determine whether the body of a function is to be repeated, due to tail-recursive function calls
        Returns:
        null if no tail call has been requested, or the name of the function to be called otherwise

      • openStackFrame

        public void openStackFrame​(SlotManager map)
        Create a new stack frame for local variables, using the supplied SlotManager to define the allocation of slots to individual variables
        Parameters:
        map - the SlotManager for the new stack frame

      • openStackFrame

        public void openStackFrame​(int numberOfVariables)
        Create a new stack frame large enough to hold a given number of local variables, for which no stack frame map is available. This is used in particular when evaluating match patterns of template rules.
        Parameters:
        numberOfVariables - The number of local variables to be accommodated.

      • setCurrentMode

        public void setCurrentMode​(Component.M mode)
        Set the current mode.
        Parameters:
        mode - the new current mode

      • setCurrentTemplateRule

        public void setCurrentTemplateRule​(Rule rule)
        Set the current template. This is used to support xsl:apply-imports. The caller is responsible for remembering the previous current template and resetting it after use.
        Parameters:
        rule - the current template rule, or null to indicate that there is no current template rule

      • setCurrentGroupIterator

        public void setCurrentGroupIterator​(GroupIterator iterator)
        Set the current grouping iterator. This supports the current-group() and current-grouping-key() functions in XSLT 2.0
        Parameters:
        iterator - the new current GroupIterator

      • setCurrentMergeGroupIterator

        public void setCurrentMergeGroupIterator​(GroupIterator iterator)
        Set the current merge group iterator. This supports the current-merge-group() and current-merge-key() functions in XSLT 3.0
        Parameters:
        iterator - the new current GroupIterator

      • setCurrentRegexIterator

        public void setCurrentRegexIterator​(RegexIterator currentRegexIterator)
        Set the current regex iterator. This supports the functionality of the regex-group() function in XSLT 2.0.
        Parameters:
        currentRegexIterator - the current regex iterator

      • useLocalParameter

        public int useLocalParameter​(StructuredQName paramName,
                             int slotNumber,
                             boolean isTunnel)
                      throws XPathException
        Use local parameter. This is called when a local xsl:param element is processed. If a parameter of the relevant name was supplied, it is bound to the xsl:param element. Otherwise the method returns false, so the xsl:param default will be evaluated
        Specified by:
        useLocalParameter in interface XPathContext
        Overrides:
        useLocalParameter in class XPathContextMinor
        Parameters:
        paramName - the name of the parameter
        slotNumber - the slot number of the parameter on the callee's stack frame
        isTunnel - True if a tunnel parameter is required, else false
        Returns:
        ParameterSet.NOT_SUPPLIED, ParameterSet.SUPPLIED, or ParameterSet.SUPPLIED_AND_CHECKED
        Throws:
        XPathException

      • setURIResolver

        public void setURIResolver​(javax.xml.transform.URIResolver resolver)
        Set an object that will be used to resolve URIs used in document(), etc. This method allows a URIResolver to be set that is local to this particular XPathContext, which is useful when local behaviour is needed, e.g. during schema validation. The URIResolver set in the Controller and in the Configuration are not affected by this call.
        Parameters:
        resolver - An object that implements the URIResolver interface, or null.
        Since:
        9.6

      • getURIResolver

        public javax.xml.transform.URIResolver getURIResolver()
        Get the URI resolver. This gets the local URIResolver set in the XPathContext if there is one; if not, it gets the URIResolver from the Controller (which itself defaults to the one set in the Configuration).
        Specified by:
        getURIResolver in interface XPathContext
        Overrides:
        getURIResolver in class XPathContextMinor
        Returns:
        the user-supplied URI resolver if there is one, or null otherwise.
        Since:
        9.6

      • setErrorReporter

        public void setErrorReporter​(ErrorReporter reporter)
        Set the error reporter. The ErrorReporter is set locally to this XPathContext object.
        Parameters:
        reporter - the ErrorReporter to be used
        Since:
        9.6. Changed in 10.0 to use the ErrorReporter interface in place of ErrorListener

      • getErrorReporter

        public ErrorReporter getErrorReporter()
        Get the error reporter. If no ErrorReporter has been set locally, the ErrorReporter in the Controller is returned; this in turn defaults to the ErrorReporter set in the Configuration.
        Specified by:
        getErrorReporter in interface XPathContext
        Overrides:
        getErrorReporter in class XPathContextMinor
        Returns:
        the ErrorReporter in use.
        Since:
        9.6. Changed in 10.0 to use an ErrorReporter rather than ErrorListener

      • setCurrentException

        public void setCurrentException​(XPathException exception)
        Set the current exception (in saxon:catch)
        Parameters:
        exception - the current exception

      • setCurrentComponent

        public void setCurrentComponent​(Component component)
        Set the current component, that is, the component being evaluated. This is used during the evaluation to determine the bindings to other components (such as global variables, functions, and templates) referenced during the evaluation
        Parameters:
        component - the current component

      • getTargetComponent

        public Component getTargetComponent​(int bindingSlot)
        Bind a component reference to a component. This is used for binding component references (such as function calls, global variable references, or xsl:call-template) across package boundaries. The binding is done dynamically because, in the presence of overridden components, the choice among different components with the same name depends on which package the caller is in.
        Specified by:
        getTargetComponent in interface XPathContext
        Overrides:
        getTargetComponent in class XPathContextMinor
        Parameters:
        bindingSlot - Binding slots are allocated statically to the external component references in every component: for example, in the case of a template, to all global variable references, named function calls, and named template calls within that template. The binding slot therefore identifies the name of the component that is required; and the selection of an actual component is done by selection from the binding vector of the component currently being executed
        Returns:
        the component to be invoked