Package net.enilink.commons.util.extensions

Class RegistryReader

  • All Implemented Interfaces:
    EventListener, org.eclipse.core.runtime.IRegistryChangeListener
    public abstract class RegistryReader
extends Object
implements org.eclipse.core.runtime.IRegistryChangeListener
    Template implementation of a registry reader that creates objects representing registry contents. Typically, an extension contains one element, but this reader handles multiple elements per extension. To start reading the extensions from the registry for an extension point, call the method readRegistry. To read children of an IConfigurationElement, call the method readElementChildren from your implementation of the method readElement, as it will not be done by default.

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      protected RegistryReader​(String pluginId, String extensionPoint)
      The constructor.
      protected RegistryReader​(org.eclipse.core.runtime.IExtensionRegistry registry, String pluginId, String extensionPoint)
      The constructor.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected String getDescription​(org.eclipse.core.runtime.IConfigurationElement config)
      This method extracts description as a subelement of the given element.
      protected static void logError​(org.eclipse.core.runtime.IConfigurationElement element, String text)
      Logs the error in the workbench log using the provided text and the information in the configuration element.
      protected static void logMissingAttribute​(org.eclipse.core.runtime.IConfigurationElement element, String attributeName)
      Logs a very common registry error when a required attribute is missing.
      protected static void logMissingElement​(org.eclipse.core.runtime.IConfigurationElement element, String elementName)
      Logs a very common registry error when a required child is missing.
      protected static void logUnknownElement​(org.eclipse.core.runtime.IConfigurationElement element)
      Logs a registry error when the configuration element is unknown.
      protected org.eclipse.core.runtime.IExtension[] orderExtensions​(org.eclipse.core.runtime.IExtension[] extensions)
      Apply a reproducable order to the list of extensions provided, such that the order will not change as extensions are added or removed.
      protected boolean readElement​(org.eclipse.core.runtime.IConfigurationElement element)
      Implement this method to read element's attributes.
      protected boolean readElement​(org.eclipse.core.runtime.IConfigurationElement element, boolean add)
      Implement this method to read element attributes for the purpose of adding or removing their registrations.
      protected void readElementChildren​(org.eclipse.core.runtime.IConfigurationElement element, boolean add)
      Read the element's children.
      protected void readElements​(org.eclipse.core.runtime.IConfigurationElement[] elements, boolean add)
      Read each element one at a time by calling the subclass implementation of readElement.
      protected void readExtension​(org.eclipse.core.runtime.IExtension extension, boolean add)
      Read one extension by looping through its configuration elements.
      void readRegistry()
      Start the registry reading process using the supplied plugin ID and extension point.
      void registerListener()
      Registers change listener to extension registry
      void registryChanged​(org.eclipse.core.runtime.IRegistryChangeEvent event)  
      void unregisterListener()
      Unregisters change listener from extension registry

    • Constructor Detail

      • RegistryReader

        protected RegistryReader​(org.eclipse.core.runtime.IExtensionRegistry registry,
                         String pluginId,
                         String extensionPoint)
        The constructor.

      • RegistryReader

        protected RegistryReader​(String pluginId,
                         String extensionPoint)
        The constructor.

    • Method Detail

      • getDescription

        protected String getDescription​(org.eclipse.core.runtime.IConfigurationElement config)
        This method extracts description as a subelement of the given element.
        Returns:
        description string if defined, or empty string if not.

      • logError

        protected static void logError​(org.eclipse.core.runtime.IConfigurationElement element,
                               String text)
        Logs the error in the workbench log using the provided text and the information in the configuration element.

      • logMissingAttribute

        protected static void logMissingAttribute​(org.eclipse.core.runtime.IConfigurationElement element,
                                          String attributeName)
        Logs a very common registry error when a required attribute is missing.

      • logMissingElement

        protected static void logMissingElement​(org.eclipse.core.runtime.IConfigurationElement element,
                                        String elementName)
        Logs a very common registry error when a required child is missing.

      • logUnknownElement

        protected static void logUnknownElement​(org.eclipse.core.runtime.IConfigurationElement element)
        Logs a registry error when the configuration element is unknown.

      • orderExtensions

        protected org.eclipse.core.runtime.IExtension[] orderExtensions​(org.eclipse.core.runtime.IExtension[] extensions)
        Apply a reproducable order to the list of extensions provided, such that the order will not change as extensions are added or removed.

      • readElement

        protected boolean readElement​(org.eclipse.core.runtime.IConfigurationElement element)
        Implement this method to read element's attributes. If children should also be read, then implementor is responsible for calling readElementChildren. Implementor is also responsible for logging missing attributes.
        Returns:
        true if element was recognized, false if not.

      • readElement

        protected boolean readElement​(org.eclipse.core.runtime.IConfigurationElement element,
                              boolean add)
        Implement this method to read element attributes for the purpose of adding or removing their registrations. If this element has child elements, the reader will recursively cycle through them and will call this method, so don't do it here.

      • readElementChildren

        protected void readElementChildren​(org.eclipse.core.runtime.IConfigurationElement element,
                                   boolean add)
        Read the element's children. This is called by the subclass' readElement method when it wants to read the children of the element.

      • readElements

        protected void readElements​(org.eclipse.core.runtime.IConfigurationElement[] elements,
                            boolean add)
        Read each element one at a time by calling the subclass implementation of readElement. Logs an error if the element was not recognized.

      • readExtension

        protected void readExtension​(org.eclipse.core.runtime.IExtension extension,
                             boolean add)
        Read one extension by looping through its configuration elements.

      • readRegistry

        public void readRegistry()
        Start the registry reading process using the supplied plugin ID and extension point.

      • registerListener

        public void registerListener()
        Registers change listener to extension registry

      • unregisterListener

        public void unregisterListener()
        Unregisters change listener from extension registry

      • registryChanged

        public void registryChanged​(org.eclipse.core.runtime.IRegistryChangeEvent event)
        Specified by:
        registryChanged in interface org.eclipse.core.runtime.IRegistryChangeListener