net.sf.saxon.expr

Class XPathContextMajor

java.lang.Object

net.sf.saxon.expr.XPathContextMinor

net.sf.saxon.expr.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.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	XPathContextMajor.ThreadManager The ThreadManager is used to manage asynchronous execution of xsl:result-document instructions in Saxon-EE.

Nested classes/interfaces inherited from class net.sf.saxon.expr.XPathContextMinor

XPathContextMinor.LastValue

Field Summary

Fields inherited from class net.sf.saxon.expr.XPathContextMinor

currentDestination, stackFrame, temporaryOutputState

Constructor Summary

Constructors

Constructor and Description
XPathContextMajor(Controller controller) Constructor should only be called by the Controller, which acts as a XPathContext factory.
XPathContextMajor(Item item, Executable exec) Constructor for use in free-standing Java applications.

Method Summary

Methods

Modifier and Type	Method and Description
void	createThreadManager() Create a new thread manager.
Sequence[]	getAllVariableValues() Get a all the variables in the stack frame
Component	getCurrentComponent() Get the current component
XPathException	getCurrentException() Get the current exception (in saxon:catch)
GroupIterator	getCurrentGroupIterator() Get the current group iterator.
GroupIterator	getCurrentMergeGroupIterator() Get the current merge group iterator.
Component<? extends Mode>	getCurrentMode() Get the current mode.
RegexIterator	getCurrentRegexIterator() Get the current regex iterator.
Rule	getCurrentTemplateRule() Get the current template.
UnfailingErrorListener	getErrorListener() Get the error listener.
ParameterSet	getLocalParameters() Get the local parameters for the current template call.
ContextOriginator	getOrigin() Get information about the creating expression or other construct.
UserFunction	getTailCallFunction() Determine whether the body of a function is to be repeated, due to tail-recursive function calls
Component	getTargetComponent(int bindingSlot) Bind a component reference to a component.
XPathContextMajor.ThreadManager	getThreadManager() Get the thread manager in use for this context.
ParameterSet	getTunnelParameters() Get the tunnel parameters for the current template call.
URIResolver	getURIResolver() Get the URI resolver.
XPathContextMajor	newContext() Construct a new context as a copy of another.
static XPathContextMajor	newContext(XPathContextMinor prev) Create a new "major" context (one that is capable of holding a stack frame with local variables
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
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.
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
void	requestTailCall(UserFunction fn, Sequence[] variables) Reset the local stack frame.
void	resetAllVariableValues(Sequence[] values) Overwrite all the variables in the stack frame
void	resetParameterValues(Sequence[] values) Overwrite all the parameters in the stack frame.
void	resetStackFrameMap(SlotManager map, int numberOfParams) Reset the stack frame variable map, while reusing the StackFrame object itself.
void	setCurrentComponent(Component component) Set the current component, that is, the component being evaluated.
void	setCurrentException(XPathException exception) Set the current exception (in saxon:catch)
void	setCurrentGroupIterator(GroupIterator iterator) Set the current grouping iterator.
void	setCurrentMergeGroupIterator(GroupIterator iterator) Set the current merge group iterator.
void	setCurrentMode(Component<? extends Mode> mode) Set the current mode.
void	setCurrentRegexIterator(RegexIterator currentRegexIterator) Set the current regex iterator.
void	setCurrentTemplateRule(Rule rule) Set the current template.
void	setErrorListener(ErrorListener listener) Set the error listener.
void	setLocalParameters(ParameterSet localParameters) Set the local parameters for the current template call.
void	setOrigin(ContextOriginator expr) Set the creating expression (for use in diagnostics).
void	setStackFrame(SlotManager map, Sequence[] variables) Set the local stack frame.
void	setTunnelParameters(ParameterSet tunnelParameters) Set the tunnel parameters for the current template call.
void	setURIResolver(URIResolver resolver) Set an object that will be used to resolve URIs used in document(), etc.
int	useLocalParameter(StructuredQName paramName, int slotNumber, boolean isTunnel) Use local parameter.
void	waitForChildThreads() Wait for child threads started under the control of this context to finish.

Methods inherited from class net.sf.saxon.expr.XPathContextMinor

evaluateLocalVariable, getCaller, getConfiguration, getContextItem, getController, getCurrentDateTime, getCurrentIterator, getCurrentOutputUri, getImplicitTimezone, getLast, getNamePool, getReceiver, getStackFrame, getTemporaryOutputState, isAtLast, iterateStackFrames, newCleanContext, newMinorContext, setCaller, setCurrentIterator, setCurrentOutputUri, setLocalVariable, setReceiver, setTemporaryOutputState

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

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

getThreadManager

public XPathContextMajor.ThreadManager getThreadManager()

Get the thread manager in use for this context.

Specified by:

getThreadManager in interface XPathContext

Overrides:

getThreadManager in class XPathContextMinor

Returns:

the current thread manager. This will be null if not running XSLT under Saxon-EE

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.

getLocalParameters

public ParameterSet getLocalParameters()

Get the local parameters for the current template call.

Specified by:

getLocalParameters in interface XPathContext

Overrides:

getLocalParameters in class XPathContextMinor

Returns:

the supplied parameters

setLocalParameters

public void setLocalParameters(ParameterSet localParameters)

Set the local parameters for the current template call.

Parameters:

localParameters - the supplied parameters

getTunnelParameters

public ParameterSet getTunnelParameters()

Get the tunnel parameters for the current template call.

Specified by:

getTunnelParameters in interface XPathContext

Overrides:

getTunnelParameters in class XPathContextMinor

Returns:

the supplied tunnel 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(UserFunction fn,
                   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:

fn - the user function being called using tail recursion

variables - the parameter to be supplied to the user function

getTailCallFunction

public UserFunction getTailCallFunction()

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<? extends Mode> mode)

Set the current mode.

Parameters:

mode - the new current mode

getCurrentMode

public Component<? extends Mode> getCurrentMode()

Get the current mode.

Specified by:

getCurrentMode in interface XPathContext

Overrides:

getCurrentMode in class XPathContextMinor

Returns:

the current mode. May return null if the current mode is the default 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

getCurrentTemplateRule

public Rule getCurrentTemplateRule()

Get the current template. This is used to support xsl:apply-imports

Specified by:

getCurrentTemplateRule in interface XPathContext

Overrides:

getCurrentTemplateRule in class XPathContextMinor

Returns:

the current template

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

getCurrentGroupIterator

public GroupIterator getCurrentGroupIterator()

Get the current group iterator. This supports the current-group() and current-grouping-key() functions in XSLT 2.0

Specified by:

getCurrentGroupIterator in interface XPathContext

Overrides:

getCurrentGroupIterator in class XPathContextMinor

Returns:

the current grouped collection

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

getCurrentMergeGroupIterator

public GroupIterator getCurrentMergeGroupIterator()

Get the current merge group iterator. This supports the current-merge-group() and current-merge-key() functions in XSLT 3.0

Specified by:

getCurrentMergeGroupIterator in interface XPathContext

Overrides:

getCurrentMergeGroupIterator in class XPathContextMinor

Returns:

the current grouped collection

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

getCurrentRegexIterator

public RegexIterator getCurrentRegexIterator()

Get the current regex iterator. This supports the functionality of the regex-group() function in XSLT 2.0.

Specified by:

getCurrentRegexIterator in interface XPathContext

Overrides:

getCurrentRegexIterator in class XPathContextMinor

Returns:

the current regular expressions 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(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 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

setErrorListener

public void setErrorListener(ErrorListener listener)

Set the error listener. The ErrorListener is set locally to this XPathContext object.

Parameters:

listener - the ErrorListener to be used

Since:

9.6

getErrorListener

public UnfailingErrorListener getErrorListener()

Get the error listener. If no ErrorListener has been set locally, the ErrorListener in the Controller is returned; this in turn defaults to the ErrorListener set in the Configuration.

Specified by:

getErrorListener in interface XPathContext

Overrides:

getErrorListener in class XPathContextMinor

Returns:

the ErrorListener in use. This will always be an UnfailingErrorListener, which is a Saxon subclass of ErrorListener that throws no exceptions.

Since:

9.6

setCurrentException

public void setCurrentException(XPathException exception)

Set the current exception (in saxon:catch)

Parameters:

exception - the current exception

getCurrentException

public XPathException getCurrentException()

Get the current exception (in saxon:catch)

Specified by:

getCurrentException in interface XPathContext

Overrides:

getCurrentException in class XPathContextMinor

Returns:

the current exception, or null if there is none defined

getCurrentComponent

public Component getCurrentComponent()

Get the current component

Specified by:

getCurrentComponent in interface XPathContext

Overrides:

getCurrentComponent in class XPathContextMinor

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