Package org.eclipse.emf.compare.rcp.extension

Class AbstractRegistryEventListener

java.lang.Object
org.eclipse.emf.compare.rcp.extension.AbstractRegistryEventListener
All Implemented Interfaces:
EventListener, org.eclipse.core.runtime.IRegistryEventListener
Direct Known Subclasses:
AccessorFactoryExtensionRegistryListener, ConfigurationUIRegistryEventListener, ContentMergeViewerCustomizationRegistryListener, DescriptorRegistryEventListener, DifferenceFilterExtensionRegistryListener, DifferenceGroupExtenderRegistryListener, DifferenceGroupProviderExtensionRegistryListener, EqualityHelperExtensionProviderDescriptorRegistryListener, LoadOnDemandPolicyRegistryListener, LogicalModelViewHandlerRegistryListener, MatchEngineFactoryRegistryListener, MergeResolutionListenerRegistryListener, MergerExtensionRegistryListener, ModelDependencyProviderRegistryListener, ModelMinimizerRegistryListener, ModelResolverRegistryListener, PostProcessorFactoryRegistryListener, ResourceSetHookRegistryListener, SubscriberProviderRegistryListener, WeightProviderDescriptorRegistryListener
public abstract class AbstractRegistryEventListener extends Object implements org.eclipse.core.runtime.IRegistryEventListener
Abstract utility class to listen to the IExtensionRegistry. It provides base implementation to added(IExtension[]) and removed(IExtension[]). Users must implement readElement(IConfigurationElement, Action) according to their extension schema.

The helper method #readRegistry() is browsing already registered extension to the extension registry making it easy to read the registry after having added the listener to it.

#readRegistry() is delegating to readElement(IConfigurationElement, Action).

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    protected static enum 
    AbstractRegistryEventListener.Action
    Enumeration that says if the IConfigurationElement is to be added or removed from the IExtensionRegistry.

  • Constructor Summary

    Constructors
    Constructor
    Description
    AbstractRegistryEventListener(String namespace, String extensionPointID, org.eclipse.core.runtime.ILog log)
    Creates a new registry event listener.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    added(org.eclipse.core.runtime.IExtension[] extensions)
    void
    added(org.eclipse.core.runtime.IExtensionPoint[] extensionPoints)
    protected abstract boolean
    addedValid(org.eclipse.core.runtime.IConfigurationElement element)
    Process the given element as the addition of a valid element extension.
    protected void
    log(int severity, org.eclipse.core.runtime.IConfigurationElement element, String message)
    Log the error to the current plugin logger.
    protected void
    log(org.eclipse.core.runtime.IConfigurationElement element, String errorMessage, Throwable cause)
    Logs the given error with a human-readable error message.
    protected void
    log(org.eclipse.core.runtime.IConfigurationElement element, Throwable t)
    Log the error to the current plugin logger.
    protected void
    logMissingAttribute(org.eclipse.core.runtime.IConfigurationElement element, String attributeName)
    Delegates the logging of a missing attribute to #log(IConfigurationElement, String) with a proper message.
    protected boolean
    readElement(org.eclipse.core.runtime.IConfigurationElement element, AbstractRegistryEventListener.Action action)
    Reads the given element.
    void
    readRegistry(org.eclipse.core.runtime.IExtensionRegistry extensionRegistry)
    Reads the given registry and call readElement(IConfigurationElement, Action) as the read IConfigurationElement were just added to it.
    void
    removed(org.eclipse.core.runtime.IExtension[] extensions)
    void
    removed(org.eclipse.core.runtime.IExtensionPoint[] extensionPoints)
    protected abstract boolean
    removedValid(org.eclipse.core.runtime.IConfigurationElement element)
    Process the given element as the removal of a valid element extension.
    protected abstract boolean
    validateExtensionElement(org.eclipse.core.runtime.IConfigurationElement element)
    Validates if the given element is an element for the given extension and is well constructed.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • AbstractRegistryEventListener

      public AbstractRegistryEventListener(String namespace, String extensionPointID, org.eclipse.core.runtime.ILog log)
      Creates a new registry event listener.
      Parameters:
      namespace - The namespace of the extension point to be monitored.
      extensionPointID - The extension point ID to be monitored
      log - The log object to be used to log error and/or warning.

  • Method Details

    • readRegistry

      public void readRegistry(org.eclipse.core.runtime.IExtensionRegistry extensionRegistry)
      Reads the given registry and call readElement(IConfigurationElement, Action) as the read IConfigurationElement were just added to it.
      Parameters:
      extensionRegistry - the registry to read.

    • readElement

      protected boolean readElement(org.eclipse.core.runtime.IConfigurationElement element, AbstractRegistryEventListener.Action action)
      Reads the given element. This method can be call when the element is added or remove. The action reflect it. It returns true if the element is recognized as valid regarding the monitored extension point. It will be call on sub elements recursively for all recognized ones.
      Parameters:
      element - the element to be read.
      action - is the element added or removed.
      Returns:
      true if the element is recognized as valid regarding the monitored extension point.

    • validateExtensionElement

      protected abstract boolean validateExtensionElement(org.eclipse.core.runtime.IConfigurationElement element)
      Validates if the given element is an element for the given extension and is well constructed. Returns true if the element should be further parsed for addition or removal.
      Parameters:
      element - the element to validate.
      Returns:
      true if the element should be further parsed for addition or removal, else otherwise.

    • addedValid

      protected abstract boolean addedValid(org.eclipse.core.runtime.IConfigurationElement element)
      Process the given element as the addition of a valid element extension.
      Parameters:
      element - the element to be added.
      Returns:
      true if the given element has been added and if its children should be processed, false otherwise.

    • removedValid

      protected abstract boolean removedValid(org.eclipse.core.runtime.IConfigurationElement element)
      Process the given element as the removal of a valid element extension.
      Parameters:
      element - the element to be removed.
      Returns:
      true if the given element has been removed and if its children should be processed, false otherwise.

    • logMissingAttribute

      protected void logMissingAttribute(org.eclipse.core.runtime.IConfigurationElement element, String attributeName)
      Delegates the logging of a missing attribute to #log(IConfigurationElement, String) with a proper message.
      Parameters:
      element - the element to which an attribute is missing.
      attributeName - the name of the missing attribute.

    • log

      protected void log(int severity, org.eclipse.core.runtime.IConfigurationElement element, String message)
      Log the error to the current plugin logger.
      Parameters:
      severity - Severity of this message. One of IStatus.OK, IStatus.ERROR, IStatus.INFO, IStatus.WARNING, or IStatus.CANCEL
      element - the element from which comes to the error.
      message - the message to be logged.

    • log

      protected void log(org.eclipse.core.runtime.IConfigurationElement element, Throwable t)
      Log the error to the current plugin logger.
      Parameters:
      element - the element from which comes to the error.
      t - the exception to be logged.

    • log

      protected void log(org.eclipse.core.runtime.IConfigurationElement element, String errorMessage, Throwable cause)
      Logs the given error with a human-readable error message.
      Parameters:
      element - The element from which originates the error.
      errorMessage - Human-readable cause of this exception.
      cause - Actual exception that is to be logged.
      Since:
      2.2

    • added

      public void added(org.eclipse.core.runtime.IExtension[] extensions)
      Specified by:
      added in interface org.eclipse.core.runtime.IRegistryEventListener
      See Also:
      • IRegistryEventListener.added(org.eclipse.core.runtime.IExtension[])

    • removed

      public void removed(org.eclipse.core.runtime.IExtension[] extensions)
      Specified by:
      removed in interface org.eclipse.core.runtime.IRegistryEventListener
      See Also:
      • IRegistryEventListener.removed(org.eclipse.core.runtime.IExtension[])

    • added

      public void added(org.eclipse.core.runtime.IExtensionPoint[] extensionPoints)
      Specified by:
      added in interface org.eclipse.core.runtime.IRegistryEventListener
      See Also:
      • IRegistryEventListener.added(org.eclipse.core.runtime.IExtensionPoint[])

    • removed

      public void removed(org.eclipse.core.runtime.IExtensionPoint[] extensionPoints)
      Specified by:
      removed in interface org.eclipse.core.runtime.IRegistryEventListener
      See Also:
      • IRegistryEventListener.removed(org.eclipse.core.runtime.IExtensionPoint[])