_UI_QueryDelegateTextViewerFactory_extensionpoint = Registered Query Delegate Text Viewer Factories

<?xml version="1.0" encoding="UTF-8"?>

<?eclipse version="3.0"?>

<plugin>

   <extension-point id="queryDelegateTextViewerFactories" name="%_UI_QueryDelegateTextViewerFactory_extensionpoint" schema="schema/queryDelegateTextViewerFactories.exsd"/>

</plugin>

<?xml version='1.0' encoding='UTF-8'?>

<!-- Schema file written by PDE -->

<schema targetNamespace="org.eclipse.emf.edit.ui" xmlns="http://www.w3.org/2001/XMLSchema">

<annotation>

      <appInfo>

         <meta.schema plugin="org.eclipse.emf.edit.ui" id="queryDelegateTextViewerFactories" name="Query Delegate Text Viewer Factory Registry"/>

      </appInfo>

      <documentation>

         This extension point is used to register factories for query delegate text viewers whose type is identified by a URI. The global EMF query delegate text viewer factory registry, <samp>QueryDelegateTextViewer.Factory.Registry.INSTANCE</samp>, is used to record the registration.

      </documentation>

   </annotation>

   <element name="extension">

      <annotation>

         <appInfo>

            <meta.element />

         </appInfo>

      </annotation>

      <complexType>

         <sequence>

            <element ref="factory" minOccurs="1" maxOccurs="unbounded"/>

         </sequence>

         <attribute name="point" type="string" use="required">

            <annotation>

               <documentation>

                  A fully qualified identifier of the target extension point.

               </documentation>

            </annotation>

         </attribute>

         <attribute name="id" type="string">

            <annotation>

               <documentation>

                  An optional identifier of the extension instance.

               </documentation>

            </annotation>

         </attribute>

         <attribute name="name" type="string">

            <annotation>

               <documentation>

                  An optional name of the extension instance.

               </documentation>

            </annotation>

         </attribute>

      </complexType>

   </element>

   <element name="factory">

      <annotation>

         <appInfo>

            <meta.element labelAttribute="id"/>

         </appInfo>

      </annotation>

      <complexType>

         <attribute name="uri" type="string" use="required">

            <annotation>

               <documentation>

                  A URI identifying the type of query delegate text viewers that can be created by the factory.

               </documentation>

            </annotation>

         </attribute>

         <attribute name="class" type="string" use="required">

            <annotation>

               <documentation>

                  The fully qualified name of a Java class implementing <samp>org.eclipse.emf.edit.ui.util.QueryDelegateTextViewer.Factory</samp>.

               </documentation>

               <appInfo>

                  <meta.attribute kind="java" basedOn="org.eclipse.emf.edit.ui.util.QueryDelegateTextViewer.Factory"/>

               </appInfo>

            </annotation>

         </attribute>

      </complexType>

   </element>

   <annotation>

      <appInfo>

         <meta.section type="since"/>

      </appInfo>

      <documentation>

         2.7.0

      </documentation>

   </annotation>

   <annotation>

      <appInfo>

         <meta.section type="examples"/>

      </appInfo>

      <documentation>

         Following is an example of how a query delegate text viewer factory can be registered: 

<pre>

  <extension point="org.eclipse.emf.edit.ui.queryDelegateTextViewerFactories" >

    <factory uri="http://www.eclipse.org/emf/2002/Ecore/OCL" class="org.eclipse.ocl.examples.interpreter.delegate.OCLQueryDelegateTextViewerFactory"/> 

  </extension>

</pre>

      </documentation>

   </annotation>

   <annotation>

      <appInfo>

         <meta.section type="apiInfo"/>

      </appInfo>

      <documentation>

         The value of the class attribute must represent a class that implements <samp>org.eclipse.emf.edit.ui.util.QueryDelegateTextViewer.Factory</samp> and has a no argument contructor.

<p>

A query delegate text viewer factory can be also registered from the source code with the <samp>QueryDelegateTextViewer.Factory.Registry.INSTANCE</samp> as follows:

</p>

<pre>

  QueryDelegateTextViewer.Factory.Registry.INSTANCE.put("http://www.eclipse.org/emf/2002/Ecore/OCL", new OCLQueryDelegateTextViewerFactory());

</pre>

      </documentation>

   </annotation>

   <annotation>

      <appInfo>

         <meta.section type="copyright"/>

      </appInfo>

      <documentation>

         Copyright (c) 2010 Kenn Hussey and others.<br>

All rights reserved. This program and the accompanying materials are made available under the terms of the Eclipse Public License v1.0 which accompanies this distribution, and is available at <a 

href="http://www.eclipse.org/legal/epl-v10.html">http://www.eclipse.org/legal/epl-v10.html</a>

      </documentation>

   </annotation>

</schema>

import org.eclipse.emf.ecore.plugin.RegistryReader;

import org.eclipse.emf.edit.ui.util.QueryDelegateTextViewer;

import org.osgi.framework.Bundle;

import org.osgi.framework.BundleContext;

  public static final String QUERY_DELEGATE_TEXT_VIEWER_FACTORIES_PPID = "queryDelegateTextViewerFactories";

    /**

     * Starts up this plugin by reading some extensions and populating the relevant registries.

     * <p>

     * @throws Exception if there is a show stopping problem.

     */

    @Override

    public void start(BundleContext context) throws Exception

    {

      super.start(context);

      Bundle bundle = Platform.getBundle("org.eclipse.jface.text");

      if (bundle != null && (bundle.getState() & (Bundle.ACTIVE | Bundle.STARTING | Bundle.RESOLVED)) != 0)

      {

        new RegistryReader(

          Platform.getExtensionRegistry(),

          EMFEditUIPlugin.getPlugin().getBundle().getSymbolicName(),

          QUERY_DELEGATE_TEXT_VIEWER_FACTORIES_PPID)

          {

            @Override

            protected boolean readElement(IConfigurationElement element, boolean add)

            {

              if (element.getName().equals("factory"))

              {

                String uri = element.getAttribute("uri");

                if (uri == null)

                {

                  logMissingAttribute(element, "uri");

                }

                else if (element.getAttribute("class") == null)

                {

                  logMissingAttribute(element, "class");

                }

                class FactoryDescriptor extends PluginClassDescriptor implements QueryDelegateTextViewer.Factory.Descriptor

                {

                  protected QueryDelegateTextViewer.Factory factory;

                  public FactoryDescriptor(IConfigurationElement e, String attrName)

                  {

                    super(e, attrName);

                  }

                  public QueryDelegateTextViewer.Factory getFactory()

                  {

                    if (factory == null)

                    {

                      factory = (QueryDelegateTextViewer.Factory)createInstance();

                    }

                    return factory;

                  }

                  public IConfigurationElement getElement()

                  {

                    return element;

                  }

                }

                if (add)

                {

                  Object previous = QueryDelegateTextViewer.Factory.Registry.INSTANCE.put(uri, new FactoryDescriptor(element, "class"));

                  if (previous instanceof FactoryDescriptor)

                  {

                    FactoryDescriptor descriptor = (FactoryDescriptor)previous;

                    EMFEditUIPlugin.INSTANCE.log("Both '" + descriptor.getElement().getContributor().getName() + "' and '"

                      + element.getContributor().getName() + "' register a query delegate text viewer factory for '" + uri + "'");

                  }

                  return true;

                }

                else

                {

                  QueryDelegateTextViewer.Factory.Registry.INSTANCE.remove(uri);

                  return true;

                }

              }

              return false;

            }

          }.readRegistry();

      }

    }

/**

 * <copyright>

 *

 * Copyright (c) 2010 Kenn Hussey and others.

 * All rights reserved.   This program and the accompanying materials

 * are made available under the terms of the Common Public License v1.0

 * which accompanies this distribution, and is available at

 * http://www.eclipse.org/legal/cpl-v10.html

 * 

 * Contributors: 

 *   Kenn Hussey - Initial API and implementation

 *

 * </copyright>

 *

 * $Id$

 */

package org.eclipse.emf.edit.ui.util;

import java.util.HashMap;

import java.util.Map;

import org.eclipse.emf.ecore.EClassifier;

import org.eclipse.jface.text.ITextViewer;

import org.eclipse.swt.widgets.Composite;

/**

 * An interface for text viewers of query delegate expressions.

 * 

 * @since 2.7

 */

public interface QueryDelegateTextViewer extends ITextViewer

{

  /**

   * A factory for creating query delegate source viewers.

   */

  interface Factory

  {

    /**

     * Creates a query delegate for the specified <tt>parent</tt>.

     * 

     * @param parent the parent container for the text viewer

     * @param styles the styles to apply to the text viewer

     * @return a query delegate text viewer

     */

    QueryDelegateTextViewer createTextViewer(Composite parent, int styles);

    /**

     * A <code>Factory</code> wrapper that is used by the {@link Factory.Registry}.

     */

    interface Descriptor

    {

      Factory getFactory();

    }

    /**

     * A registry of query delegate text viewer factories.

     */

    interface Registry extends Map<String, Object>

    {

      Registry INSTANCE = new Impl();

      Factory getFactory(String uri);

      class Impl extends HashMap<String, Object> implements Registry

      {

        private static final long serialVersionUID = 1L;

        @Override

        public Object get(Object key)

        {

          Object factory = super.get(key);

          if (factory instanceof Descriptor)

          {

            Descriptor factoryDescriptor = (Descriptor)factory;

            factory = factoryDescriptor.getFactory();

            put((String)key, factory);

            return factory;

          }

          else

          {

            return factory;

          }

        }

        public Factory getFactory(String uri)

        {

          return (Factory)get(uri);

        }

      }

    }

  }

  /**

   * Sets the context for the text viewer's query.

   * 

   * @param context the type of object against which the query will be executed

   */

  void setContext(EClassifier context);

  /**

   * Sets the parameters for the text viewer's query.

   * 

   * @param parameters a map of parameter names to types

   */

  void setParameters(Map<String, EClassifier> parameters);

}