org.apache.wiki.util

Class PropertyReader

java.lang.Object

org.apache.wiki.util.PropertyReader

public final class PropertyReader
extends Object

Property Reader for the WikiEngine. Reads the properties for the WikiEngine and implements the feature of cascading properties and variable substitution, which come in handy in a multi wiki installation environment: It reduces the need for (shell) scripting in order to generate different jspwiki.properties to a minimum.

Since:

2.5.x

Field Summary

Fields

Modifier and Type	Field and Description
static String	CUSTOM_JSPWIKI_CONFIG
static String	DEFAULT_JSPWIKI_CONFIG Path to the base property file, usually overridden by values provided in a jspwiki-custom.properties file "/ini/jspwiki.properties"
static String	PARAM_CUSTOMCONFIG The servlet context parameter (from web.xml) that defines where the config file is to be found.
static String	PARAM_CUSTOMCONFIG_CASCADEPREFIX The prefix when you are cascading properties.

Method Summary

Modifier and Type	Method and Description
static void	expandVars(Properties properties) You define a property variable by using the prefix "var.x" as a property.
static Properties	getCombinedProperties(String fileName) Returns a property set consisting of the default Property Set overlaid with a custom property set
static Properties	getDefaultProperties() Returns the property set as a Properties object.
static Properties	loadWebAppProps(javax.servlet.ServletContext context) Loads the webapp properties based on servlet context information, or (if absent) based on the Java System Property PARAM_CUSTOMCONFIG .
static InputStream	locateClassPathResource(javax.servlet.ServletContext context, String resourceName) Locate a resource stored in the class path.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_JSPWIKI_CONFIG

public static final String DEFAULT_JSPWIKI_CONFIG

Path to the base property file, usually overridden by values provided in a jspwiki-custom.properties file "/ini/jspwiki.properties"

See Also:

Constant Field Values

PARAM_CUSTOMCONFIG

public static final String PARAM_CUSTOMCONFIG

The servlet context parameter (from web.xml) that defines where the config file is to be found. If it is not defined, checks the Java System Property, if that is not defined either, uses the default as defined by DEFAULT_PROPERTYFILE. "/ini/jspwiki.properties"

See Also:

Constant Field Values

PARAM_CUSTOMCONFIG_CASCADEPREFIX

public static final String PARAM_CUSTOMCONFIG_CASCADEPREFIX

The prefix when you are cascading properties.

See Also:

loadWebAppProps(ServletContext), Constant Field Values

CUSTOM_JSPWIKI_CONFIG

public static final String CUSTOM_JSPWIKI_CONFIG

See Also:

Constant Field Values

Method Detail

loadWebAppProps

public static Properties loadWebAppProps(javax.servlet.ServletContext context)

Loads the webapp properties based on servlet context information, or (if absent) based on the Java System Property PARAM_CUSTOMCONFIG . Returns a Properties object containing the settings, or null if unable to load it. (The default file is ini/jspwiki.properties, and can be customized by setting PARAM_CUSTOMCONFIG in the server or webapp configuration.)

Cascading Properties

You can define additional property files and merge them into the default properties file in a similar process to how you define cascading style sheets; hence we call this cascading property files. This way you can overwrite the default values and only specify the properties you need to change in a multiple wiki environment.

You define a cascade in the context mapping of your servlet container.

  jspwiki.custom.cascade.1
  jspwiki.custom.cascade.2
  jspwiki.custom.cascade.3
  

and so on. You have to number your cascade in a descending way starting with "1". This means you cannot leave out numbers in your cascade. This method is based on an idea by Olaf Kaus, see [JSPWiki:MultipleWikis].

Parameters:

context - A Servlet Context which is used to find the properties

Returns:

A filled Properties object with all the cascaded properties in place

getDefaultProperties

public static Properties getDefaultProperties()

Returns the property set as a Properties object.

Returns:

A property set.

getCombinedProperties

public static Properties getCombinedProperties(String fileName)

Returns a property set consisting of the default Property Set overlaid with a custom property set

Parameters:

fileName - Reference to the custom override file

Returns:

A property set consisting of the default property set and custom property set, with the latter's properties replacing the former for any common values

expandVars

public static void expandVars(Properties properties)

You define a property variable by using the prefix "var.x" as a property. In property values you can then use the "$x" identifier to use this variable. For example you could declare a base directory for all your files like this and use it in all your other property definitions with a "$basedir". Note that it does not matter if you define the variable before its usage.

  var.basedir = /p/mywiki;
  jspwiki.fileSystemProvider.pageDir =         $basedir/www/
  jspwiki.basicAttachmentProvider.storageDir = $basedir/www/
  jspwiki.workDir =                            $basedir/wrk/
  

Parameters:

properties - - properties to expand;

locateClassPathResource

public static InputStream locateClassPathResource(javax.servlet.ServletContext context,
                                                  String resourceName)

Locate a resource stored in the class path. Try first with "WEB-INF/classes" from the web app and fallback to "resourceName".

Parameters:

context - the servlet context

resourceName - the name of the resource

Returns:

the input stream of the resource or null if the resource was not found