com.opensymphony.module.sitemesh.mapper

Class ConfigLoader

java.lang.Object

com.opensymphony.module.sitemesh.mapper.ConfigLoader

public class ConfigLoader
extends java.lang.Object

The ConfigLoader reads a configuration XML file that contains Decorator definitions (name, url, init-params) and path-mappings (pattern, name).

These can then be accessed by the getDecoratorByName() methods and getMappedName() methods respectively.

The DTD for the configuration file in old (deprecated) format is located at http://www.opensymphony.com/dtds/sitemesh_1_0_decorators.dtd .

The DTD for the configuration file in new format is located at http://www.opensymphony.com/dtds/sitemesh_1_5_decorators.dtd .

Editing the config file will cause it to be auto-reloaded.

This class is used by ConfigDecoratorMapper, and uses PathMapper for pattern matching.

Version:

$Revision: 1.8 $

Author:

Joe Walnes, Mathias Bogaert

See Also:

ConfigDecoratorMapper, PathMapper

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	ConfigLoader.State State visibile across threads stored in a single container so that we can efficiently atomically access it with the guarantee that we wont see a partially loaded configuration in the face of one thread reloading the configuration while others are trying to read it.

Field Summary

Fields

Modifier and Type	Field and Description
private Config	config
private java.io.File	configFile
private java.lang.String	configFileName
private ConfigLoader.State	state Mark volatile so that the installation of new versions is guaranteed to be visible across threads.

Constructor Summary

Constructors

Constructor and Description
ConfigLoader(java.io.File configFile) Create new ConfigLoader using supplied File.
ConfigLoader(java.lang.String configFileName, Config config) Create new ConfigLoader using supplied filename and config.

Method Summary

Modifier and Type	Method and Description
private static java.lang.String	getAttribute(org.w3c.dom.Element element, java.lang.String name)
private static java.lang.String	getContainedText(org.w3c.dom.Node parent, java.lang.String childTagName)
Decorator	getDecoratorByName(java.lang.String name) Retrieve Decorator based on name specified in configuration file.
java.lang.String	getMappedName(java.lang.String path) Get name of Decorator mapped to given path.
private ConfigLoader.State	loadConfig() Load configuration from file.
private void	parseConfig(ConfigLoader.State newState, org.w3c.dom.Document document)
private void	populatePathMapper(ConfigLoader.State newState, org.w3c.dom.NodeList patternNodes, java.lang.String role, java.lang.String name)
private ConfigLoader.State	refresh() Check if configuration file has been updated, and if so, reload.
private void	storeDecorator(ConfigLoader.State newState, Decorator d)

Methods inherited from class java.lang.Object

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

Field Detail

state

private volatile ConfigLoader.State state

Mark volatile so that the installation of new versions is guaranteed to be visible across threads.

configFile

private java.io.File configFile

configFileName

private java.lang.String configFileName

config

private Config config

Constructor Detail

ConfigLoader

public ConfigLoader(java.io.File configFile)
             throws javax.servlet.ServletException

Create new ConfigLoader using supplied File.

Throws:

javax.servlet.ServletException

ConfigLoader

public ConfigLoader(java.lang.String configFileName,
                    Config config)
             throws javax.servlet.ServletException

Create new ConfigLoader using supplied filename and config.

Throws:

javax.servlet.ServletException

Method Detail

getDecoratorByName

public Decorator getDecoratorByName(java.lang.String name)
                             throws javax.servlet.ServletException

Retrieve Decorator based on name specified in configuration file.

Throws:

javax.servlet.ServletException

getMappedName

public java.lang.String getMappedName(java.lang.String path)
                               throws javax.servlet.ServletException

Get name of Decorator mapped to given path.

Throws:

javax.servlet.ServletException

loadConfig

private ConfigLoader.State loadConfig()
                               throws javax.servlet.ServletException

Load configuration from file.

Throws:

javax.servlet.ServletException

parseConfig

private void parseConfig(ConfigLoader.State newState,
                         org.w3c.dom.Document document)

populatePathMapper

private void populatePathMapper(ConfigLoader.State newState,
                                org.w3c.dom.NodeList patternNodes,
                                java.lang.String role,
                                java.lang.String name)

getAttribute

private static java.lang.String getAttribute(org.w3c.dom.Element element,
                                             java.lang.String name)

getContainedText

private static java.lang.String getContainedText(org.w3c.dom.Node parent,
                                                 java.lang.String childTagName)

storeDecorator

private void storeDecorator(ConfigLoader.State newState,
                            Decorator d)

refresh

private ConfigLoader.State refresh()
                            throws javax.servlet.ServletException

Check if configuration file has been updated, and if so, reload.

Throws:

javax.servlet.ServletException