org.cdlib.xtf.servletBase

Class StylesheetCache

Object

Cache<K,V>

GeneratingCache

StylesheetCache

public class StylesheetCache
extends GeneratingCache

This class is used to cache stylesheets so they don't have to be reloaded each time they're used.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	StylesheetCache.DepResolver While loading a stylesheet, we record all the sub-stylesheets referenced by it, so that we can form a list of all the dependencies.
static interface	StylesheetCache.TraceListenerFactory

Nested classes/interfaces inherited from class Cache

Cache.ListEntry, Cache.NullIterator

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	dependencyChecking
private GeneratingCache	dependencyReceiver
private TransformerFactory	factory
private StylesheetCache.TraceListenerFactory	traceListenerFactory

Fields inherited from class Cache

ageList, keyMap

Constructor Summary

Constructors

Constructor and Description
StylesheetCache(int maxEntries, int maxTime, boolean dependencyChecking) Constructor.

Method Summary

Modifier and Type	Method and Description
void	enableProfiling(StylesheetCache.TraceListenerFactory tlf) Enable or disable profiling (only affects stylesheets that are not already cached).
Templates	find(String path) Locate the stylesheet for the given filesystem path.
protected Object	generate(Object key) Load and parse a stylesheet from the filesystem.
protected void	logAction(String action, Object key, Object value) Prints out useful debugging info

Methods inherited from class GeneratingCache

addDependency, find

Methods inherited from class Cache

cleanup, clear, dependenciesValid, getDependencies, has, lastSet, remove, size

Methods inherited from class Object

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

Field Detail

dependencyChecking

private boolean dependencyChecking

dependencyReceiver

private GeneratingCache dependencyReceiver

traceListenerFactory

private StylesheetCache.TraceListenerFactory traceListenerFactory

factory

private TransformerFactory factory

Constructor Detail

StylesheetCache

public StylesheetCache(int maxEntries,
                       int maxTime,
                       boolean dependencyChecking)

Constructor.

Parameters:

maxEntries - Max # of entries before old ones are flushed

maxTime - Max age (in seconds) before an entry is flushed.

dependencyChecking - Whether to keep track of dependencies and invalidate cache entries when dependents are updated.

Method Detail

find

public Templates find(String path)
               throws Exception

Locate the stylesheet for the given filesystem path. If not cached, then load it.

Parameters:

path - Filesystem path of the stylesheet to load

Returns:

The parsed stylesheet

Throws:

Exception - If the stylesheet could not be loaded.

enableProfiling

public void enableProfiling(StylesheetCache.TraceListenerFactory tlf)

Enable or disable profiling (only affects stylesheets that are not already cached). If the factory is null, profiling is disabled.

generate

protected Object generate(Object key)
                   throws Exception

Load and parse a stylesheet from the filesystem.

Specified by:

generate in class GeneratingCache

Parameters:

key - (String)Filesystem path of the stylesheet to load

Returns:

The parsed stylesheet

Throws:

Exception - If the stylesheet could not be loaded.

logAction

protected void logAction(String action,
                         Object key,
                         Object value)

Prints out useful debugging info

Overrides:

logAction in class Cache

Parameters:

action - What happened ("Added", "Removed", etc.)

key - The key involved in the action

value - The value involved in the action