/*
* Copyright 2004-2006 the original author or authors.
*
* 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.
*/
package org.compass.core.converter.xsem;
import org.compass.core.Property;
import org.compass.core.Resource;
import org.compass.core.converter.ConversionException;
import org.compass.core.converter.Converter;
import org.compass.core.engine.naming.PropertyPath;
import org.compass.core.mapping.Mapping;
import org.compass.core.mapping.ResourcePropertyMapping;
import org.compass.core.mapping.xsem.XmlPropertyMapping;
import org.compass.core.marshall.MarshallingContext;
import org.compass.core.xml.XmlObject;
/**
* A simple converter which uses the String value of {@link org.compass.core.xml.XmlObject#getValue()}.
* It is the deafult converter associated with the value converter of {@link XmlPropertyMapping} if none
* is specified. It can also be used as a base class for more specialized converters.
*
* @author kimchy
*/
public class SimpleXmlValueConverter implements Converter {
public boolean marshall(Resource resource, Object root, Mapping mapping, MarshallingContext context) throws ConversionException {
XmlPropertyMapping xmlPropertyMapping = (XmlPropertyMapping) mapping;
// don't save a null value if the context does not states so
if (root == null && !handleNulls(xmlPropertyMapping, context)) {
return false;
}
XmlObject xmlObject = (XmlObject) root;
String sValue = getNullValue(xmlPropertyMapping, context);
if (root != null) {
sValue = toString(xmlObject, xmlPropertyMapping);
}
PropertyPath path = xmlPropertyMapping.getPath();
String propertyName = path == null ? null : path.getPath();
if (propertyName == null) {
if (xmlObject == null) {
// nothing we can do here, no name, no nothing...
return false;
}
propertyName = xmlObject.getName();
}
Property p = context.getResourceFactory().createProperty(propertyName, sValue, xmlPropertyMapping);
doSetBoost(p, root, xmlPropertyMapping, context);
resource.addProperty(p);
return xmlPropertyMapping.getStore() != Property.Store.NO;
}
/**
* <p>Should the converter handle nulls? Handling nulls means should the
* converter process nulls or not. Usually the converter will not
* persist null values, but sometimes it might be needed
* ({@link org.compass.core.marshall.MarshallingContext#handleNulls()}).
*
* <p>If a specific null value is configured with the {@link org.compass.core.mapping.ResourcePropertyMapping}
* then the converter will always handle nulls and write it.
*
* @param context The marshalling context
* @return <code>true</code> if the converter should handle null values
*/
protected boolean handleNulls(ResourcePropertyMapping resourcePropertyMapping, MarshallingContext context) {
return resourcePropertyMapping.hasNullValue() || context.handleNulls();
}
/**
* If the converter handle nulls, the value that will be stored in the
* search engine for <code>null</code> values (during the marshall process). Uses
* {@link org.compass.core.mapping.ResourcePropertyMapping#getNullValue()}.
*
* @param resourcePropertyMapping The resource proeprty mapping to get the null value from
* @param context The marshalling context
* @return Null value that will be inserted for <code>null</code>s.
*/
protected String getNullValue(ResourcePropertyMapping resourcePropertyMapping, MarshallingContext context) {
return resourcePropertyMapping.getNullValue();
}
/**
* A simple extension point that allows to set the boost value for the created {@link Property}.
* <p/>
* The default implemenation uses the statically defined boost value in the mapping definition
* ({@link org.compass.core.mapping.ResourcePropertyMapping#getBoost()}) to set the boost level
* using {@link Property#setBoost(float)}
*
* @param property The property to set the boost on
* @param root The object that is marshalled into a property
* @param resourcePropertyMapping The Resource Property Mapping definition
* @throws ConversionException
*/
protected void doSetBoost(Property property, Object root, ResourcePropertyMapping resourcePropertyMapping,
MarshallingContext context) throws ConversionException {
property.setBoost(resourcePropertyMapping.getBoost());
}
/**
* Default implementation of toString, simply calls {@link org.compass.core.xml.XmlObject#getValue()}.
*/
public String toString(XmlObject xmlObject, ResourcePropertyMapping resourcePropertyMapping) {
return xmlObject.getValue();
}
/**
* Not supported operation.
*/
public Object unmarshall(Resource resource, Mapping mapping, MarshallingContext context) throws ConversionException {
return new ConversionException("Not supported");
}
}
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