/*
* 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) 2001 - 2009 Object Refinery Ltd, Pentaho Corporation and Contributors.. All rights reserved.
*/
package org.pentaho.reporting.engine.classic.core.metadata.parser;
import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.util.ArrayList;
import java.util.HashMap;
import org.pentaho.reporting.engine.classic.core.function.Expression;
import org.pentaho.reporting.engine.classic.core.metadata.DefaultExpressionMetaData;
import org.pentaho.reporting.libraries.base.util.ObjectUtilities;
import org.pentaho.reporting.libraries.xmlns.parser.AbstractXmlReadHandler;
import org.pentaho.reporting.libraries.xmlns.parser.ParseException;
import org.pentaho.reporting.libraries.xmlns.parser.XmlReadHandler;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
/**
* Todo: Document Me
*
* @author Thomas Morgner
*/
public class ExpressionReadHandler extends AbstractXmlReadHandler
{
private String bundleName;
private Class expressionClass;
private Class resultType;
private String prefix;
private boolean expert;
private boolean hidden;
private boolean preferred;
private boolean deprecated;
private ArrayList attributeHandlers;
private BeanInfo beanInfo;
private HashMap properties;
private int layoutComputation;
public ExpressionReadHandler()
{
attributeHandlers = new ArrayList();
properties = new HashMap();
}
/**
* Starts parsing.
*
* @param attrs the attributes.
* @throws SAXException if there is a parsing error.
*/
protected void startParsing(final Attributes attrs) throws SAXException
{
bundleName = attrs.getValue(getUri(), "bundle-name");
expert = "true".equals(attrs.getValue(getUri(), "expert"));
hidden = "true".equals(attrs.getValue(getUri(), "hidden"));
preferred = "true".equals(attrs.getValue(getUri(), "preferred"));
deprecated = "true".equals(attrs.getValue(getUri(), "deprecated"));
final String layoutProcessorMode = attrs.getValue(getUri(), "layout-processor-mode");
if ("global".equals(layoutProcessorMode))
{
layoutComputation = DefaultExpressionMetaData.GLOBAL_LAYOUT_PROCESSOR;
}
else if ("element".equals(layoutProcessorMode))
{
layoutComputation = DefaultExpressionMetaData.ELEMENT_LAYOUT_PROCESSOR;
}
else
{
layoutComputation = DefaultExpressionMetaData.NO_LAYOUT_PROCESSOR;
}
final String valueTypeText = attrs.getValue(getUri(), "class");
if (valueTypeText == null)
{
throw new ParseException("Attribute 'class' is undefined", getLocator());
}
try
{
final ClassLoader loader = ObjectUtilities.getClassLoader(ExpressionReadHandler.class);
expressionClass = Class.forName(valueTypeText, false, loader);
if (Expression.class.isAssignableFrom(expressionClass) == false)
{
throw new ParseException("Attribute 'class' is not valid", getLocator());
}
}
catch (ParseException pe)
{
throw pe;
}
catch (Exception e)
{
throw new ParseException("Attribute 'class' is not valid", e, getLocator());
}
try
{
beanInfo = Introspector.getBeanInfo(expressionClass);
}
catch (IntrospectionException e)
{
throw new ParseException("Cannot introspect specified " + expressionClass, getLocator());
}
prefix = "expression." + expressionClass.getName();
final String resultType = attrs.getValue(getUri(), "result");
if (resultType == null)
{
throw new ParseException("Attribute 'result' is undefined", getLocator());
}
try
{
final ClassLoader loader = ObjectUtilities.getClassLoader(ExpressionReadHandler.class);
this.resultType = Class.forName(resultType, false, loader);
}
catch (Exception e)
{
throw new ParseException("Attribute 'result' is not valid", e, getLocator());
}
}
/**
* Returns the handler for a child element.
*
* @param uri the URI of the namespace of the current element.
* @param tagName the tag name.
* @param atts the attributes.
* @return the handler or null, if the tagname is invalid.
* @throws SAXException if there is a parsing error.
*/
protected XmlReadHandler getHandlerForChild(final String uri,
final String tagName,
final Attributes atts) throws SAXException
{
if (getUri().equals(uri) == false)
{
return null;
}
if ("property".equals(tagName))
{
final ExpressionPropertyReadHandler readHandler =
new ExpressionPropertyReadHandler(beanInfo, bundleName, prefix + ".property.");
attributeHandlers.add(readHandler);
return readHandler;
}
return null;
}
/**
* Done parsing.
*
* @throws SAXException if there is a parsing error.
*/
protected void doneParsing() throws SAXException
{
for (int i = 0; i < attributeHandlers.size(); i++)
{
final ExpressionPropertyReadHandler handler = (ExpressionPropertyReadHandler) attributeHandlers.get(i);
final String attrName = handler.getName();
properties.put(attrName, handler.getObject());
}
}
/**
* Returns the object for this element or null, if this element does not create an object.
*
* @return the object.
* @throws SAXException if an parser error occured.
*/
public Object getObject() throws SAXException
{
return new DefaultExpressionMetaData(bundleName, "expression.", expert, preferred, hidden, deprecated,
expressionClass, resultType, properties, beanInfo, layoutComputation);
}
}