HQLBaseComponent.java

/*
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html 
 * or from the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * Copyright 2006 - 2009 Pentaho Corporation.  All rights reserved.
 *
 *
 * Created Dec 27, 2006
 * @author mdamour
 */
package org.pentaho.platform.plugin.action.hql;

import java.io.File;
import java.util.ArrayList;
import java.util.Map;
import java.util.StringTokenizer;

import org.apache.commons.logging.Log;
import org.pentaho.actionsequence.dom.ActionInputConstant;
import org.pentaho.actionsequence.dom.IActionOutput;
import org.pentaho.actionsequence.dom.IActionResource;
import org.pentaho.actionsequence.dom.actions.HQLConnectionAction;
import org.pentaho.actionsequence.dom.actions.HQLQueryAction;
import org.pentaho.commons.connection.IPentahoConnection;
import org.pentaho.commons.connection.IPentahoResultSet;
import org.pentaho.platform.api.data.IPreparedComponent;
import org.pentaho.platform.api.engine.IActionSequenceResource;
import org.pentaho.platform.engine.core.system.PentahoSystem;
import org.pentaho.platform.engine.services.connection.PentahoConnectionFactory;
import org.pentaho.platform.engine.services.runtime.MapParameterResolver;
import org.pentaho.platform.engine.services.runtime.TemplateUtil;
import org.pentaho.platform.engine.services.solution.ComponentBase;
import org.pentaho.platform.plugin.action.messages.Messages;
import org.pentaho.platform.plugin.services.connections.hql.HQLConnection;

public abstract class HQLBaseComponent extends ComponentBase implements IPreparedComponent {

  private static final long serialVersionUID = 5949258346877934670L;

  private IPentahoResultSet rSet;

  /** reference to connection object */
  private IPentahoConnection connection;

  /** specifies whether component owns connection or not */
  private boolean connectionOwner = true;

  /** holds the query string for ipreparedcomponent functionality */
  private String preparedQuery = null;

  @Override
  public abstract boolean validateSystemSettings();

  public abstract String getResultOutputName();

  @Override
  public abstract Log getLogger();

  public IPentahoResultSet getResultSet() {
    return rSet;
  }

  @Override
  protected boolean validateAction() {
    HQLConnectionAction connAction = null;
    HQLQueryAction queryAction = null;
    boolean actionValidated = true;

    try {
      if (getActionDefinition() instanceof HQLQueryAction) {
        queryAction = (HQLQueryAction) getActionDefinition();

        actionValidated = isConnectionInfoSpecified(queryAction);

        // Check if the query is defined.
        if (actionValidated && (queryAction.getQuery() == ActionInputConstant.NULL_INPUT)) {
          actionValidated = false;
          error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0004_QUERY_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$
        }

        // Check if output for the query is correctly defined.                  
        if (actionValidated && (queryAction.getOutputResultSetName() == null)
            && (queryAction.getOutputPreparedStatementName() == null)) {
          actionValidated = false;
          error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0005_OUTPUT_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$
        }
      } else if (getActionDefinition() instanceof HQLConnectionAction) {
        connAction = (HQLConnectionAction) getActionDefinition();
        actionValidated = isConnectionInfoSpecified(connAction);
      } else {
        actionValidated = false;
        error(Messages.getInstance().getErrorString(
            "ComponentBase.ERROR_0001_UNKNOWN_ACTION_TYPE", getActionDefinition().getElement().asXML())); //$NON-NLS-1$      
      }
    } catch (Exception e) {
      actionValidated = false;
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0006_VALIDATION_FAILED", getActionName()), e); //$NON-NLS-1$     
    }

    return actionValidated;
  }

  private boolean isConnectionInfoSpecified(final HQLConnectionAction connAction) {
    boolean value = true;

    if (connAction instanceof HQLQueryAction) {
      if ((((HQLQueryAction) connAction).getInputSharedConnection() == ActionInputConstant.NULL_INPUT)
          && !isBasicConnectionInfoSpecified(connAction)) {
        value = false;
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0003_CONNECTION_INFO_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$        
      }
    } else {
      if (!isBasicConnectionInfoSpecified(connAction)) {
        value = false;
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0003_CONNECTION_INFO_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$        
      }
    }
    return value;
  }

  private boolean isBasicConnectionInfoSpecified(final HQLConnectionAction connAction) {
    boolean value = true;

    if (connAction.getClassNames() == ActionInputConstant.NULL_INPUT) {
      value = false;
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0001_CLASS_NAMES_INFO_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$  
    }
    if (connAction.getHibernateConfigResource() == null) {
      value = false;
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0002_HIBERNATE_CONFIG_INFO_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$        
    }

    return value;
  }

  @Override
  public void done() {
    // TODO Auto-generated method stub
  }

  @Override
  protected boolean executeAction() {
    boolean returnValue = true;

    try {
      if (getActionDefinition() instanceof HQLQueryAction) {
        HQLQueryAction queryAction = (HQLQueryAction) getActionDefinition();
        String classNames[] = null;
        String query = queryAction.getQuery().getStringValue();

        if (queryAction.getInputSharedConnection() != ActionInputConstant.NULL_INPUT) {
          connectionOwner = false;
          IPreparedComponent component = (IPreparedComponent) queryAction.getInputSharedConnection().getValue();
          IPentahoConnection conn = component.shareConnection();
          if (IPentahoConnection.HQL_DATASOURCE.equals(conn.getDatasourceType())) {
            connection = conn;
          } else {
            connection = null;
            returnValue = false;
            error(Messages.getInstance().getErrorString("IPreparedComponent.ERROR_0001_INVALID_CONNECTION_TYPE", getActionName())); //$NON-NLS-1$            
          }
        } else {
          createBasicConnection(queryAction, classNames);
        }

        if (connection != null) {
          IActionOutput actionOutput = queryAction.getOutputPreparedStatementParam();
          if (actionOutput != null) {
            // prepare the query for execution, but don't execute quite yet.
            prepareQuery(query);

            // set the output as self, which will be used later by another component.
            actionOutput.setValue(this);
          } else {
            return runQuery(connection, classNames, query);
          }
        }
      } else if (getActionDefinition() instanceof HQLConnectionAction) {
        HQLConnectionAction connAction = (HQLConnectionAction) getActionDefinition();
        String classNames[] = null;
        createBasicConnection(connAction, classNames);
        if (connection != null) {
          IActionOutput outputConnection = connAction.getOutputConnectionParam();
          if (outputConnection != null) {
            outputConnection.setValue(this);
          }
        }
      } else {
        returnValue = false;
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00011_INVALID_HQL_COMPONENT", getActionName())); //$NON-NLS-1$
      }
    } catch (Exception e) {
      returnValue = false;
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00012_EXECUTE_FAILED", getActionName()), e); //$NON-NLS-1$
    }
    return returnValue;
  }

  /*
   * Create the basic connection. This requires retrieving class names and catalog info. 
   */
  private void createBasicConnection(final HQLConnectionAction connAction, String[] classNames) {
    boolean proceed = true;
    String catalog = null;

    if (connAction.getClassNames() != ActionInputConstant.NULL_INPUT) {
      classNames = getClassNames(connAction);
    } else {
      proceed = false;
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0001_CLASS_NAMES_INFO_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$ 
    }

    if (proceed) {
      catalog = getCatalog();

      if ((null == catalog) || (catalog.trim().length() <= 0)) {
        proceed = false;
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00010_CATALOG_INFO_NOT_SPECIFIED", getActionName())); //$NON-NLS-1$
      }
    }

    if (proceed) {
      connection = getConnection(new File(catalog), classNames);

      if (connection == null) {
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0009_COULD_NOT_ESTABLISH_CONNECTION", getActionName())); //$NON-NLS-1$
      }
    }
  }

  /*
   * Utitlity function to get the class names from the XML.
   */
  private String[] getClassNames(final HQLConnectionAction connAction) {
    ArrayList classNamesList = new ArrayList();
    String classNames[] = null;
    try {
      String classes = connAction.getClassNames().getStringValue();
      StringTokenizer st = new StringTokenizer(classes, ",");//getInputStringValue(CLASSNAMES), ","); //$NON-NLS-1$
      while (st.hasMoreTokens()) {
        String token = st.nextToken();
        classNamesList.add(token.trim());
      }

      classNames = (String[]) classNamesList.toArray(new String[0]);

    } catch (Exception e) {
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0008_COULD_NOT_RETRIEVE_CLASS_NAMES", getActionName()), e); //$NON-NLS-1$
    }

    return classNames;
  }

  /*
   * Utility function to get the catalog info from hibernate config.
   */
  private String getCatalog() {
    IActionResource hibernateConfigRes = ((HQLConnectionAction) getActionDefinition()).getHibernateConfigResource();
    String catalog = null;
    String resAddress = null;
    
    if (hibernateConfigRes != null) {
      String resName = this.applyInputsToFormat(hibernateConfigRes.getName());
      IActionSequenceResource resource = getResource(resName);
      resAddress = resource.getAddress();
      if (resAddress != null) {
        catalog = this.applyInputsToFormat(resAddress);
      }
      if (resource.getSourceType() == IActionSequenceResource.SOLUTION_FILE_RESOURCE) {
        catalog = PentahoSystem.getApplicationContext().getSolutionPath(catalog);
      }
    }
    return catalog;
  }

  /**
   * called when in prepared-component mode, this method populates the preparedQuery string and
   * preparedParameters object.
   * 
   * @param rawQuery
   * @return
   */
  protected boolean prepareQuery(final String rawQuery) {

    try {
      if (connection == null) {
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00013_NO_CONNECTION")); //$NON-NLS-1$
        return false;
      }
      if (!connection.initialized()) {
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00013_NO_CONNECTION")); //$NON-NLS-1$
        return false;
      }
      if (rawQuery != null) {
        preparedQuery = applyInputsToFormat(rawQuery);
      }

      return true;
    } catch (Exception e) {
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00014_COULD_NOT_PREPARE_QUERY", getActionName()), e); //$NON-NLS-1$
    }

    return false;
  }

  /**
   * executes a prepared method that returns a result set
   * executePrepared looks up any "PREPARELATER" params
   * in the preparedParams map.
   *
   * @param preparedParams a map of possible parameters.
   * @return result set
   */
  public IPentahoResultSet executePrepared(final Map preparedParams) {
    try {
      if (connection == null) {
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0009_COULD_NOT_ESTABLISH_CONNECTION")); //$NON-NLS-1$
        return null;
      }
      if (!connection.initialized()) {
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0009_COULD_NOT_ESTABLISH_CONNECTION")); //$NON-NLS-1$
        return null;
      }

      if (preparedQuery == null) {
        error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00016_QUERY_NOT_SPECIFIED")); //$NON-NLS-1$
        return null;
      }

      // parse preparedQuery, replacing any {PREPARELATER:NAME} with appropriate values 
      String query = TemplateUtil.applyTemplate(preparedQuery, getRuntimeContext(), new MapParameterResolver(
          preparedParams, IPreparedComponent.PREPARE_LATER_PREFIX, getRuntimeContext()));

      if (ComponentBase.debug) {
        debug(Messages.getInstance().getString("HQLBaseComponent.DEBUG_RUNNING_QUERY", query)); //$NON-NLS-1$
      }

      // evaluate 
      IPentahoResultSet resultSet = connection.executeQuery(query);
      rSet = resultSet;
      return resultSet;
    } catch (Exception e) {
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_00012_EXECUTE_FAILED", getActionName()), e); //$NON-NLS-1$
    }
    return null;
  }

  protected boolean runQuery(final IPentahoConnection conn, final String[] classNames, final String query) {
    try {

      if (conn == null) {
        return false;
      }

      rSet = ((HQLConnection) conn).executeQuery(query);

      IActionOutput actionOutput = ((HQLQueryAction) getActionDefinition()).getOutputResultSetParam();
      if (actionOutput != null) {
        actionOutput.setValue(rSet);
      }
      return true;
    } catch (Exception e) {
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0007_QUERY_EXECUTION_FAILED", getActionName()), e); //$NON-NLS-1$
      return false;
    }
  }

  /**
   * if the owner, dispose of the connection
   */
  public void dispose() {
    if (connectionOwner) {
      if (connection != null) {
        connection.close();
      }
    }
    connection = null;
  }

  protected IPentahoConnection getConnection(final File hbmCfgFile, final String classNames[]) {
    IPentahoConnection conn = null;
    try {
      conn = (HQLConnection) PentahoConnectionFactory.getConnection("HQL", getSession(), this); //$NON-NLS-1$
      HQLConnection hconn = (HQLConnection) conn;
      hconn.setConfigFile(hbmCfgFile);
      hconn.setClassNames(classNames);
      return conn;
    } catch (Exception e) {
      error(Messages.getInstance().getErrorString("HQLBaseComponent.ERROR_0009_COULD_NOT_ESTABLISH_CONNECTION", getActionName()), e); //$NON-NLS-1$
    }
    return null;
  }

  /**
   * return this class's connection.  This implements the IPreparedComponent
   * interface, which may share its connection with others.
   * 
   * @return connection object
   */
  public IPentahoConnection shareConnection() {
    return connection;
  }

  @Override
  public boolean init() {
    return true;
  }
}