org.cdlib.xtf.lazyTree
Class LazyProfilingListener

Object
  LazyProfilingListener

All Implemented Interfaces:

EventListener, TraceListener

public class LazyProfilingListener
extends Object
implements TraceListener

Used to keep track of the current instruction being executed, and to keep track of counts for each one.

Author:

Martin Haye

Nested Class Summary

static class

LazyProfilingListener.ProfileCount Simple data structure to keep track of counts.

Field Summary

private static LazyProfilingListener.ProfileCount	emptyInstr Dummy used for counting nodes when no instruction is specified
private ThreadLocal	tlCountMap Keeps a count of how many nodes are accessed by each instruction.
private ThreadLocal	tlInstructionStack Stack of instructions, used to keep track of what XSLT instruction is being processed.

Constructor Summary

LazyProfilingListener()

Method Summary

void	bumpCount(int nodeNum) Increases the count by one for the current instruction.
void	close() Unused
void	endCurrentItem(Item currentItem) Unused
void	enter(InstructionInfo instruction, XPathContext context) Record the instruction being entered, so that subsequent counts can be attributed to it.
private HashMap	getCountMap() Get a thread-local count map
LazyProfilingListener.ProfileCount[]	getCounts() Gets a list of all the counts, sorted by ascending count.
private LinkedList	getInstructionStack() Get a thread-local instruction stack
void	leave(InstructionInfo instruction) Called when an instruction is exited.
void	open() Unused
void	printProfile() Prints the results of a trace run, to Trace.info().
void	startCurrentItem(Item currentItem) Unused

Methods inherited from class Object

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

Field Detail

tlInstructionStack

private ThreadLocal tlInstructionStack

Stack of instructions, used to keep track of what XSLT instruction is being processed. Must be thread-local, since the same stylesheet may be in use by multiple threads at one time.

emptyInstr

private static final LazyProfilingListener.ProfileCount emptyInstr

Dummy used for counting nodes when no instruction is specified

tlCountMap

private ThreadLocal tlCountMap

Keeps a count of how many nodes are accessed by each instruction. Must be thread-local, since the same stylesheet may be in use by multiple threads at one time.

Constructor Detail

LazyProfilingListener

public LazyProfilingListener()

Method Detail

open

public void open()

Unused

Specified by:

open in interface TraceListener

close

public void close()

Unused

Specified by:

close in interface TraceListener

getInstructionStack

private LinkedList getInstructionStack()

Get a thread-local instruction stack

getCountMap

private HashMap getCountMap()

Get a thread-local count map

enter

public void enter(InstructionInfo instruction,
                  XPathContext context)

Record the instruction being entered, so that subsequent counts can be attributed to it.

Specified by:

enter in interface TraceListener

leave

public void leave(InstructionInfo instruction)

Called when an instruction is exited. Subsequent counts get applied to the instruction that was previously active.

Specified by:

leave in interface TraceListener

startCurrentItem

public void startCurrentItem(Item currentItem)

Unused

Specified by:

startCurrentItem in interface TraceListener

endCurrentItem

public void endCurrentItem(Item currentItem)

Unused

Specified by:

endCurrentItem in interface TraceListener

bumpCount

public void bumpCount(int nodeNum)

Increases the count by one for the current instruction.

getCounts

public LazyProfilingListener.ProfileCount[] getCounts()

Gets a list of all the counts, sorted by ascending count. The act of getting the counts clears out the table, so that a fresh profile can be made of the next run.

printProfile

public void printProfile()
                  throws IOException

Prints the results of a trace run, to Trace.info().

Throws:

IOException