net.sf.saxon.trace

Interface TraceListener

public interface TraceListener extends EventListener

This interface defines methods that are called by Saxon during the execution of a stylesheet, if tracing is switched on. Tracing can be switched on by nominating an implementation of this class using the TRACE_LISTENER feature of the TransformerFactory, or using the addTraceListener() method of the Controller, which is Saxon's implementation of tyhe JAXP javax.xml.transform.Transformer interface.
Method Summary
voidclose()
Method called at the end of execution, that is, when the run-time execution ends
voidendCurrentItem(Item currentItem)
Method that is called when an instruction has finished processing a new current item and is ready to select a new current item or revert to the previous current item.
voidenter(InstructionInfo instruction, XPathContext context)
Method that is called when an instruction in the stylesheet gets processed.
voidleave(InstructionInfo instruction)
Method that is called after processing an instruction of the stylesheet, that is, after any child instructions have been processed.
voidopen()
Method called at the start of execution, that is, when the run-time transformation starts
voidstartCurrentItem(Item currentItem)
Method that is called by an instruction that changes the current item in the source document: that is, xsl:for-each, xsl:apply-templates, xsl:for-each-group.

Method Detail

close

public void close()
Method called at the end of execution, that is, when the run-time execution ends

endCurrentItem

public void endCurrentItem(Item currentItem)
Method that is called when an instruction has finished processing a new current item and is ready to select a new current item or revert to the previous current item. The method will be called before the leave() method for the instruction that made this item current.

Parameters: currentItem the item that was current, whose processing is now complete. This will represent the same underlying item as the corresponding startCurrentItem() call, though it will not necessarily be the same actual object.

enter

public void enter(InstructionInfo instruction, XPathContext context)
Method that is called when an instruction in the stylesheet gets processed.

Parameters: instruction gives information about the instruction being executed, and about the context in which it is executed. This object is mutable, so if information from the InstructionInfo is to be retained, it must be copied.

leave

public void leave(InstructionInfo instruction)
Method that is called after processing an instruction of the stylesheet, that is, after any child instructions have been processed.

Parameters: instruction gives the same information that was supplied to the enter method, though it is not necessarily the same object. Note that the line number of the instruction is that of the start tag in the source stylesheet, not the line number of the end tag.

open

public void open()
Method called at the start of execution, that is, when the run-time transformation starts

startCurrentItem

public void startCurrentItem(Item currentItem)
Method that is called by an instruction that changes the current item in the source document: that is, xsl:for-each, xsl:apply-templates, xsl:for-each-group. The method is called after the enter method for the relevant instruction, and is called once for each item processed.

Parameters: currentItem the new current item. Item objects are not mutable; it is safe to retain a reference to the Item for later use.