Class PluginCreateRule

java.lang.Object
org.apache.commons.digester.Rule
org.apache.commons.digester.plugins.PluginCreateRule
All Implemented Interfaces:
InitializableRule
public class PluginCreateRule extends Rule implements InitializableRule
Allows the original rules for parsing the configuration file to define points at which plugins are allowed, by configuring a PluginCreateRule with the appropriate pattern.
Since:
1.6

  • Constructor Details

    • PluginCreateRule

      public PluginCreateRule(Class<?> baseClass)
      Create a plugin rule where the user must specify a plugin-class or plugin-id.
      Parameters:
      baseClass - is the class which any specified plugin must be descended from.

    • PluginCreateRule

      public PluginCreateRule(Class<?> baseClass, Class<?> dfltPluginClass)
      Create a plugin rule where the user may specify a plugin. If the user doesn't specify a plugin, then the default class specified in this constructor is used.
      Parameters:
      baseClass - is the class which any specified plugin must be descended from.
      dfltPluginClass - is the class which will be used if the user doesn't specify any plugin-class or plugin-id. This class will have custom rules installed for it just like a declared plugin.

    • PluginCreateRule

      public PluginCreateRule(Class<?> baseClass, Class<?> dfltPluginClass, RuleLoader dfltPluginRuleLoader)
      Create a plugin rule where the user may specify a plugin. If the user doesn't specify a plugin, then the default class specified in this constructor is used.
      Parameters:
      baseClass - is the class which any specified plugin must be descended from.
      dfltPluginClass - is the class which will be used if the user doesn't specify any plugin-class or plugin-id. This class will have custom rules installed for it just like a declared plugin.
      dfltPluginRuleLoader - is a RuleLoader instance which knows how to load the custom rules associated with this default plugin.

  • Method Details

    • setPluginClassAttribute

      public void setPluginClassAttribute(String namespaceUri, String attrName)
      Sets the xml attribute which the input xml uses to indicate to a PluginCreateRule which class should be instantiated.

      See PluginRules.setPluginClassAttribute(String, String) for more info.

    • setPluginIdAttribute

      public void setPluginIdAttribute(String namespaceUri, String attrName)
      Sets the xml attribute which the input xml uses to indicate to a PluginCreateRule which plugin declaration is being referenced.

      See PluginRules.setPluginIdAttribute(String, String) for more info.

    • postRegisterInit

      public void postRegisterInit(String matchPattern) throws PluginConfigurationException
      Invoked after this rule has been added to the set of digester rules, associated with the specified pattern. Check all configuration data is valid and remember the pattern for later.
      Specified by:
      postRegisterInit in interface InitializableRule
      Parameters:
      matchPattern - is the digester match pattern that is associated with this rule instance, eg "root/widget".
      Throws:
      PluginConfigurationException

    • begin

      public void begin(String namespace, String name, Attributes attributes) throws Exception
      Invoked when the Digester matches this rule against an xml element.

      A new instance of the target class is created, and pushed onto the stack. A new "private" PluginRules object is then created and set as the digester's default Rules object. Any custom rules associated with the plugin class are then loaded into that new Rules object. Finally, any custom rules that are associated with the current pattern (such as SetPropertiesRules) have their begin methods executed.

      Overrides:
      begin in class Rule
      Parameters:
      namespace -
      name -
      attributes -
      Throws:
      ClassNotFoundException
      PluginInvalidInputException
      PluginConfigurationException
      Exception

    • body

      public void body(String namespace, String name, String text) throws Exception
      Process the body text of this element.
      Overrides:
      body in class Rule
      Parameters:
      namespace - the namespace URI of the matching element, or an empty string if the parser is not namespace aware or the element has no namespace
      name - the local name if the parser is namespace aware, or just the element name otherwise
      text - The body text of this element
      Throws:
      Exception

    • end

      public void end(String namespace, String name) throws Exception
      Invoked by the digester when the closing tag matching this Rule's pattern is encountered.

      Overrides:
      end in class Rule
      Parameters:
      namespace - Description of the Parameter
      name - Description of the Parameter
      Throws:
      Exception - Description of the Exception
      See Also:

    • getPattern

      public String getPattern()
      Return the pattern that this Rule is associated with.

      In general, Rule instances can be associated with multiple patterns. A PluginCreateRule, however, will only function correctly when associated with a single pattern. It is possible to fix this, but I can't be bothered just now because this feature is unlikely to be used.

      Returns:
      The pattern value

    • fireBeginMethods

      public void fireBeginMethods(List<Rule> rules, String namespace, String name, Attributes list) throws Exception
      Duplicate the processing that the Digester does when firing the begin methods of rules. It would be really nice if the Digester class provided a way for this functionality to just be invoked directly.
      Throws:
      Exception

    • fireEndMethods

      public void fireEndMethods(List<Rule> rules, String namespaceURI, String name) throws Exception
      Duplicate the processing that the Digester does when firing the end methods of rules. It would be really nice if the Digester class provided a way for this functionality to just be invoked directly.
      Throws:
      Exception