/*
* 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 (c) 2009 Pentaho Corporation.. All rights reserved.
*/
package org.pentaho.reporting.engine.classic.core.filter.types;
import java.sql.Blob;
import java.util.Locale;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.reporting.engine.classic.core.AttributeNames;
import org.pentaho.reporting.engine.classic.core.Element;
import org.pentaho.reporting.engine.classic.core.SubReport;
import org.pentaho.reporting.engine.classic.core.function.ExpressionRuntime;
import org.pentaho.reporting.engine.classic.core.metadata.ElementMetaData;
import org.pentaho.reporting.engine.classic.core.metadata.ElementType;
import org.pentaho.reporting.engine.classic.core.metadata.ElementTypeRegistry;
import org.pentaho.reporting.libraries.base.util.IOUtils;
import org.pentaho.reporting.libraries.base.util.ObjectUtilities;
import org.pentaho.reporting.libraries.resourceloader.Resource;
import org.pentaho.reporting.libraries.resourceloader.ResourceKey;
import org.pentaho.reporting.libraries.resourceloader.ResourceManager;
/**
* Todo: Document me!
* <p/>
* Date: 01.06.2009
* Time: 13:35:08
*
* @author Thomas Morgner.
*/
public class ExternalElementType implements ElementType
{
public static final ElementType INSTANCE = new ExternalElementType();
private transient ElementMetaData elementType;
private static final Log logger = LogFactory.getLog(ExternalElementType.class);
public ExternalElementType()
{
}
public void configureDesignTimeDefaults(final Element element, final Locale locale)
{
}
public ElementMetaData getMetaData()
{
if (elementType == null)
{
elementType = ElementTypeRegistry.getInstance().getElementType("external-element-field");
}
return elementType;
}
public Object getDesignValue(final ExpressionRuntime runtime, final Element element)
{
final Object staticValue = ElementTypeUtils.queryStaticValue(element);
if (staticValue != null)
{
return staticValue;
}
return ElementTypeUtils.queryFieldName(element);
}
/**
* Returns the current value for the data source.
*
* @param runtime the expression runtime that is used to evaluate formulas and expressions when computing the value of
* this filter.
* @param element the element for which the data is computed.
* @return the value.
*/
public Object getValue(final ExpressionRuntime runtime, final Element element)
{
if (runtime == null)
{
throw new NullPointerException("Runtime must never be null.");
}
if (element == null)
{
throw new NullPointerException("Element must never be null.");
}
final Object value = ElementTypeUtils.queryFieldOrValue(runtime, element);
if (value != null)
{
final Object filteredValue = filter(runtime, element, value);
if (filteredValue != null)
{
return filteredValue;
}
}
final Object nullValue = element.getAttribute(AttributeNames.Core.NAMESPACE, AttributeNames.Core.NULL_VALUE);
return filter(runtime, element, nullValue);
}
private Object filter(final ExpressionRuntime runtime, final Element element, final Object value)
{
if (value instanceof Element)
{
return value;
}
try
{
final ResourceKey contentBase = runtime.getProcessingContext().getContentBase();
final ResourceManager resManager = runtime.getProcessingContext().getResourceManager();
final ResourceKey key;
if (value instanceof ResourceKey)
{
key = (ResourceKey) value;
}
else if (value instanceof Blob)
{
final Blob b = (Blob) value;
final byte[] data = IOUtils.getInstance().readBlob(b);
key = resManager.createKey(data);
}
else if (value instanceof String)
{
final Object baseURL = element.getAttribute(AttributeNames.Core.NAMESPACE, AttributeNames.Core.CONTENT_BASE);
if (baseURL != null)
{
final ResourceKey baseKey = resManager.createKey(baseURL);
key = resManager.deriveKey(baseKey, (String) value);
}
else
{
key = resManager.deriveKey(contentBase, (String) value);
}
}
else
{
key = resManager.createKey(value);
}
if (key == null)
{
return null;
}
Class target;
Object targetRaw = element.getAttribute(AttributeNames.Core.NAMESPACE, AttributeNames.Core.TARGET_TYPE);
if (targetRaw instanceof String)
{
final ClassLoader loader = ObjectUtilities.getClassLoader(ExternalElementType.class);
target = Class.forName((String) targetRaw, false, loader);
if (target == null)
{
return null;
}
}
else
{
target = SubReport.class;
}
final Resource resource = resManager.create(key, contentBase, target);
final Object resourceContent = resource.getResource();
if (resourceContent instanceof Element)
{
return resourceContent;
}
}
catch (Exception e)
{
logger.warn("Failed to load content using value " + value, e);
}
return null;
}
/**
* Clones this <code>DataSource</code>.
*
* @return the clone.
* @throws CloneNotSupportedException this should never happen.
*/
public Object clone() throws CloneNotSupportedException
{
return super.clone();
}
}