net.sf.saxon.expr

Class XPathContextMajor

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.

Field Summary

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

stackFrame

Constructor Summary

XPathContextMajor(Controller controller)
Constructor should only be called by the Controller, which acts as a XPathContext factory.
XPathContextMajor(Item item, Configuration config)
Deprecated. since 9.0 - use XPathContextMajor(Item,Executable)
XPathContextMajor(Item item, Executable exec)
Constructor for use in free-standing Java applications.

Method Summary

GroupIterator
getCurrentGroupIterator()
Get the current group iterator.
Mode
getCurrentMode()
Get the current mode.
RegexIterator
getCurrentRegexIterator()
Get the current regex iterator.
Rule
getCurrentTemplateRule()
Get the current template.
ParameterSet
getLocalParameters()
Get the local parameters for the current template call.
UserFunction
getTailCallFunction()
Determine whether the body of a function is to be repeated, due to tail-recursive function calls
ParameterSet
getTunnelParameters()
Get the tunnel parameters for the current template call.
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
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, ValueRepresentation[] variables)
Reset the local stack frame.
void
resetStackFrameMap(SlotManager map, int numberOfParams)
Reset the stack frame variable map, while reusing the StackFrame object itself.
void
setCurrentGroupIterator(GroupIterator iterator)
Set the current grouping iterator.
void
setCurrentMode(Mode mode)
Set the current mode.
void
setCurrentRegexIterator(RegexIterator currentRegexIterator)
Set the current regex iterator.
void
setCurrentTemplateRule(Rule rule)
Set the current template.
void
setLocalParameters(ParameterSet localParameters)
Set the local parameters for the current template call.
void
setOrigin(InstructionInfoProvider expr)
Set the creating expression (for use in diagnostics).
void
setStackFrame(SlotManager map, ValueRepresentation[] variables)
Set the local stack frame.
void
setTunnelParameters(ParameterSet tunnelParameters)
Set the tunnel parameters for the current template call.
boolean
useLocalParameter(StructuredQName qName, LocalParam binding, boolean isTunnel)
Use local parameter.

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

changeOutputDestination, evaluateLocalVariable, getCaller, getCollation, getConfiguration, getContextItem, getContextPosition, getController, getCurrentDateTime, getCurrentGroupIterator, getCurrentIterator, getCurrentMode, getCurrentRegexIterator, getCurrentTemplateRule, getDefaultCollation, getImplicitTimezone, getLast, getLocalParameters, getNameChecker, getNamePool, getOrigin, getOriginatingConstructType, getReceiver, getStackFrame, getTunnelParameters, isAtLast, newCleanContext, newContext, newMinorContext, setCaller, setCurrentIterator, setLocalVariable, setOrigin, setOriginatingConstructType, setReceiver, setTemporaryReceiver, useLocalParameter

Constructor Details

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,
                         Configuration config)

Deprecated. since 9.0 - use XPathContextMajor(Item,Executable)

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).
config - the Saxon Configuration

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 Details

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 interface XPathContextMinor
Returns:
the current grouped collection

getCurrentMode

public Mode getCurrentMode()
Get the current mode.
Specified by:
getCurrentMode in interface XPathContext
Overrides:
getCurrentMode in interface XPathContextMinor
Returns:
the current mode. May return null if the current mode is the default mode.

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 interface XPathContextMinor
Returns:
the current regular expressions iterator

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 interface XPathContextMinor
Returns:
the current template

getLocalParameters

public ParameterSet getLocalParameters()
Get the local parameters for the current template call.
Specified by:
getLocalParameters in interface XPathContext
Overrides:
getLocalParameters in interface XPathContextMinor
Returns:
the supplied parameters

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

getTunnelParameters

public ParameterSet getTunnelParameters()
Get the tunnel parameters for the current template call.
Specified by:
getTunnelParameters in interface XPathContext
Overrides:
getTunnelParameters in interface XPathContextMinor
Returns:
the supplied tunnel parameters

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 interface XPathContextMinor

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

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.

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

requestTailCall

public void requestTailCall(UserFunction fn,
                            ValueRepresentation[] 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

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

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

setCurrentMode

public void setCurrentMode(Mode mode)
Set the current mode.
Parameters:
mode - the new current mode

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

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

setLocalParameters

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

setOrigin

public void setOrigin(InstructionInfoProvider 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 InstructionInfoProvider, allowing information about the calling instruction to be obtained, or null.
Specified by:
setOrigin in interface XPathContext
Overrides:
setOrigin in interface XPathContextMinor

setStackFrame

public void setStackFrame(SlotManager map,
                          ValueRepresentation[] 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

setTunnelParameters

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

useLocalParameter

public boolean useLocalParameter(StructuredQName qName,
                                 LocalParam binding,
                                 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 interface XPathContextMinor
Parameters:
qName - The fingerprint of the parameter name
binding - The XSLParam element to bind its value to
isTunnel - True if a tunnel parameter is required, else false
Returns:
true if a parameter of this name was supplied, false if not