BaseUIComponent.java

/*
 * 
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU General Public License, version 2 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/gpl-2.0.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 General Public License for more details.
 *
 *
 * Copyright 2005 - 2008 Pentaho Corporation.  All rights reserved. 
 * 
 * @created  Jul 22, 2005 
 * @author James Dixon
 * 
 */

package org.pentaho.platform.uifoundation.component;

import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.List;

import org.apache.commons.logging.Log;
import org.pentaho.platform.api.engine.IActionRequestHandler;
import org.pentaho.platform.api.engine.IParameterProvider;
import org.pentaho.platform.api.engine.IPentahoSession;
import org.pentaho.platform.api.engine.IPentahoUrlFactory;
import org.pentaho.platform.api.ui.IUIComponent;
import org.pentaho.platform.engine.core.system.PentahoSystem;
import org.pentaho.platform.engine.services.PentahoMessenger;
import org.pentaho.platform.uifoundation.messages.Messages;
import org.pentaho.platform.util.messages.LocaleHelper;

/**
 * @author James Dixon
 * 
 * TODO To change the template for this generated type comment go to Window -
 * Preferences - Java - Code Style - Code Templates
 */
public abstract class BaseUIComponent extends PentahoMessenger implements IUIComponent {

  private static final long serialVersionUID = -6768653568134000758L;

  public static final boolean debug = PentahoSystem.debug;

  protected HashMap xslProperties;

  protected HashMap contentTypes;

  private IActionRequestHandler requestHandler;

  private IPentahoSession userSession;

  @Override
  public abstract Log getLogger();

  private HashMap parameterProviders;

  protected IPentahoUrlFactory urlFactory;

  private String sourcePath;

  public void handleRequest(final OutputStream outputStream, final IActionRequestHandler actionRequestHandler,
      final String contentType, final HashMap requestParameterProviders) throws IOException {

    this.parameterProviders = requestParameterProviders;
    this.requestHandler = actionRequestHandler;
    String content = getContent(contentType);
    if (content != null) {
      outputStream.write(content.getBytes(LocaleHelper.getSystemEncoding()));
    } else {
      error(Messages.getInstance().getString("BaseUI.ERROR_0001_NO_CONTENT")); //$NON-NLS-1$
    }
  }

  protected void setSourcePath(final String sourcePath) {
    this.sourcePath = sourcePath;
  }

  protected String getSourcePath() {
    return sourcePath;
  }

  public void setUrlFactory(final IPentahoUrlFactory urlFactory) {
    this.urlFactory = urlFactory;
  }

  public void setRequestHandler(final IActionRequestHandler actionRequestHandler) {
    this.requestHandler = actionRequestHandler;
  }

  public BaseUIComponent(final IPentahoUrlFactory urlFactory, final List messages, final String sourcePath) {
    super();
    this.urlFactory = urlFactory;
    xslProperties = new HashMap();
    contentTypes = new HashMap();
    setMessages(messages);
    parameterProviders = new HashMap();
    this.sourcePath = sourcePath;
  }

  public void setParameterProvider(final String name, final IParameterProvider parameterProvider) {
    if (parameterProviders == null) {
      parameterProviders = new HashMap();
    }
    parameterProviders.put(name, parameterProvider);
  }

  public void setParameterProviders(final HashMap parameterProviders) {
    this.parameterProviders = parameterProviders;
  }

  protected IPentahoUrlFactory getUrlFactory() {
    return urlFactory;
  }

  protected IActionRequestHandler getRequestHandler() {
    return requestHandler;
  }

  public HashMap getParameterProviders() {
    return parameterProviders;
  }

  public String getParameter(final String name, final String defaultValue) {
    IParameterProvider parameterProvider = (IParameterProvider) parameterProviders.get("options"); //$NON-NLS-1$
    String value = null;
    if (parameterProvider != null) {
      value = parameterProvider.getStringParameter(name, null);
      if (value != null) {
        return value;
      }
    }
    parameterProvider = (IParameterProvider) parameterProviders.get(IParameterProvider.SCOPE_REQUEST);
    if (parameterProvider != null) {
      value = parameterProvider.getStringParameter(name, null);
      if (value != null) {
        return value;
      }
    }
    if (parameterProvider != null) {
      value = parameterProvider.getStringParameter(name, null);
      if (value != null) {
        return value;
      }
    }
    return defaultValue;
  }

  public Object getObjectParameter(final String name, final Object defaultValue) {
    IParameterProvider parameterProvider = (IParameterProvider) parameterProviders.get("options"); //$NON-NLS-1$
    Object value = null;
    if (parameterProvider != null) {
      value = parameterProvider.getParameter(name);
      if (value != null) {
        return value;
      }
    }
    parameterProvider = (IParameterProvider) parameterProviders.get(IParameterProvider.SCOPE_REQUEST);
    if (parameterProvider != null) {
      value = parameterProvider.getParameter(name);
      if (value != null) {
        return value;
      }
    }
    if (parameterProvider != null) {
      value = parameterProvider.getParameter(name);
      if (value != null) {
        return value;
      }
    }
    return defaultValue;
  }
  
  public String[] getParameterAsArray(final String name) {
    IParameterProvider parameterProvider = (IParameterProvider) parameterProviders.get("options"); //$NON-NLS-1$
    Object value;
    if (parameterProvider != null) {
      value = parameterProvider.getParameter(name);
      if (value != null) {
        return toStringArray(value);
      }
    }
    parameterProvider = (IParameterProvider) parameterProviders.get(IParameterProvider.SCOPE_REQUEST);
    if (parameterProvider != null) {
      value = parameterProvider.getParameter(name);
      if (value != null) {
        return toStringArray(value);
      }
    }
    parameterProvider = (IParameterProvider) parameterProviders.get(IParameterProvider.SCOPE_SESSION);
    if (parameterProvider != null) {
      value = parameterProvider.getParameter(name);
      if (value != null) {
        return toStringArray(value);
      }
    }
    return (new String[] {});
  }

  private String[] toStringArray(final Object value) {
    if (value == null) {
      return (new String[] {});
    }

    if (value instanceof String[]) {
      return ((String[]) value);
    }

    return (new String[] { value.toString() });
  }

  protected IPentahoSession getSession() {
    return userSession;
  }

  public void setXsl(final String mimeType, final String xslName) {
    contentTypes.put(mimeType, xslName);
  }

  public String getXsl(final String mimeType) {
    return (String) contentTypes.get(mimeType);
  }

  public abstract boolean validate();

  /**
   * Set the userSession member, generate a Log Id, set the requestHandler, and validate 
   * the component's configuration.
   * NOTE: this method has several side effects not related to validation. could
   * probably use some refactoring
   * 
   * @param session
   * @param actionRequestHandler
   * @return boolean true if component configuration is valid, else false
   */
  public boolean validate(final IPentahoSession session, final IActionRequestHandler actionRequestHandler) {
    this.userSession = session;
    this.genLogIdFromSession(session);
    this.requestHandler = actionRequestHandler;
    return validate();
  }

  public void setXslProperty(final String name, final String value) {
    xslProperties.put(name, value);
  }

  public HashMap getXslProperties() {
    return xslProperties;
  }

  public abstract String getContent(String mimeType);

  public void done() {

  }

}