ImportRulePluginType.java

/*! ******************************************************************************
 *
 * Pentaho Data Integration
 *
 * Copyright (C) 2002-2013 by Pentaho : http://www.pentaho.com
 *
 *******************************************************************************
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
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package org.pentaho.di.core.plugins;

import java.io.InputStream;
import java.lang.annotation.Annotation;
import java.util.List;
import java.util.Map;

import org.pentaho.di.core.Const;
import org.pentaho.di.core.annotations.ImportRulePlugin;
import org.pentaho.di.core.exception.KettlePluginException;
import org.pentaho.di.core.exception.KettleXMLException;
import org.pentaho.di.core.xml.XMLHandler;
import org.pentaho.di.imp.rule.ImportRuleInterface;
import org.w3c.dom.Document;
import org.w3c.dom.Node;

/**
 * This is the import rule plugin type.
 *
 * @author matt
 *
 */
@PluginMainClassType( ImportRuleInterface.class )
@PluginAnnotationType( ImportRulePlugin.class )
public class ImportRulePluginType extends BasePluginType implements PluginTypeInterface {

  private static ImportRulePluginType pluginType;

  private ImportRulePluginType() {
    super( ImportRulePlugin.class, "IMPORT_RULE", "Import rule" );
    populateFolders( "rules" );
  }

  public static ImportRulePluginType getInstance() {
    if ( pluginType == null ) {
      pluginType = new ImportRulePluginType();
    }
    return pluginType;
  }

  /**
   * Scan & register internal step plugins
   */
  protected void registerNatives() throws KettlePluginException {
    // Scan the native steps...
    //
    String kettleImportRulesXmlFile = Const.XML_FILE_KETTLE_IMPORT_RULES;

    // Load the plugins for this file...
    //
    try {
      InputStream inputStream = getClass().getResourceAsStream( kettleImportRulesXmlFile );
      if ( inputStream == null ) {
        inputStream = getClass().getResourceAsStream( "/" + kettleImportRulesXmlFile );
      }
      if ( inputStream == null ) {
        throw new KettlePluginException( "Unable to find native import rules definition file: "
          + Const.XML_FILE_KETTLE_IMPORT_RULES );
      }
      Document document = XMLHandler.loadXMLFile( inputStream, null, true, false );

      // Document document = XMLHandler.loadXMLFile(kettleStepsXmlFile);

      Node stepsNode = XMLHandler.getSubNode( document, "rules" );
      List<Node> stepNodes = XMLHandler.getNodes( stepsNode, "rule" );
      for ( Node stepNode : stepNodes ) {
        registerPluginFromXmlResource( stepNode, null, this.getClass(), true, null );
      }

    } catch ( KettleXMLException e ) {
      throw new KettlePluginException( "Unable to read the kettle steps XML config file: "
        + kettleImportRulesXmlFile, e );
    }
  }

  /**
   * Scan & register internal step plugins
   */
  protected void registerAnnotations() throws KettlePluginException {
    // This is no longer done because it was deemed too slow. Only jar files in the plugins/ folders are scanned for
    // annotations.
  }

  protected void registerXmlPlugins() throws KettlePluginException {
    // Not supported, ignored
  }

  @Override
  protected String extractCategory( Annotation annotation ) {
    return "";
  }

  @Override
  protected String extractDesc( Annotation annotation ) {
    return ( (ImportRulePlugin) annotation ).description();
  }

  @Override
  protected String extractID( Annotation annotation ) {
    return ( (ImportRulePlugin) annotation ).id();
  }

  @Override
  protected String extractName( Annotation annotation ) {
    return ( (ImportRulePlugin) annotation ).name();
  }

  @Override
  protected String extractImageFile( Annotation annotation ) {
    return null;
  }

  @Override
  protected boolean extractSeparateClassLoader( Annotation annotation ) {
    return false;
  }

  @Override
  protected String extractI18nPackageName( Annotation annotation ) {
    return ( (ImportRulePlugin) annotation ).i18nPackageName();
  }

  @Override
  protected void addExtraClasses( Map<Class<?>, String> classMap, Class<?> clazz, Annotation annotation ) {
  }

  @Override
  protected String extractDocumentationUrl( Annotation annotation ) {
    return null;
  }

  @Override
  protected String extractCasesUrl( Annotation annotation ) {
    return null;
  }

  @Override
  protected String extractForumUrl( Annotation annotation ) {
    return null;
  }

  @Override
  protected String extractClassLoaderGroup( Annotation annotation ) {
    return ( (ImportRulePlugin) annotation ).classLoaderGroup();
  }
}