/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.tika.xmp.convert;
import java.util.Set;
import org.apache.tika.exception.TikaException;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.metadata.Property;
import com.adobe.xmp.XMPConst;
import com.adobe.xmp.XMPException;
import com.adobe.xmp.XMPMeta;
import com.adobe.xmp.XMPMetaFactory;
import com.adobe.xmp.XMPSchemaRegistry;
import com.adobe.xmp.XMPUtils;
import com.adobe.xmp.options.PropertyOptions;
/**
* Base class for Tika Metadata to XMP converter which provides some needed common functionality.
*/
public abstract class AbstractConverter implements ITikaToXMPConverter {
private Metadata metadata;
protected XMPMeta meta;
abstract public XMPMeta process(Metadata metadata) throws XMPException;
/**
* Every Converter has to provide information about namespaces that are used additionally to the
* core set of XMP namespaces.
*
* @return the additional namespace information
*/
abstract protected Set<Namespace> getAdditionalNamespaces();
public AbstractConverter() throws TikaException {
meta = XMPMetaFactory.create();
metadata = new Metadata();
registerNamespaces( getAdditionalNamespaces() );
}
public void setMetadata(Metadata metadata) {
this.metadata = metadata;
}
public XMPMeta getXMPMeta() {
return meta;
}
// --- utility methods used by sub-classes ---
/**
* Registers a number <code>Namespace</code> information with XMPCore. Any already registered
* namespace is not registered again.
*
* @param namespaces
* the list of namespaces to be registered
* @throws TikaException
* in case a namespace oculd not be registered
*/
protected void registerNamespaces(Set<Namespace> namespaces) throws TikaException {
XMPSchemaRegistry registry = XMPMetaFactory.getSchemaRegistry();
for (Namespace namespace : namespaces) {
// Any already registered namespace is not registered again
try {
registry.registerNamespace( namespace.uri, namespace.prefix );
}
catch (XMPException e) {
throw new TikaException(
"Namespace needed by converter could not be registiered with XMPCore", e );
}
}
}
/**
* @see AbstractConverter#createProperty(String, String, String)
*/
protected void createProperty(Property metadataProperty, String ns, String propertyName)
throws XMPException {
createProperty( metadataProperty.getName(), ns, propertyName );
}
/**
* Creates a simple property.
*
* @param tikaKey
* Key in the Tika metadata map
* @param ns
* namespace the property should be created in
* @param propertyName
* name of the property
* @throws XMPException
* if the property could not be created
*/
protected void createProperty(String tikaKey, String ns, String propertyName)
throws XMPException {
String value = metadata.get( tikaKey );
if (value != null && value.length() > 0) {
meta.setProperty( ns, propertyName, value );
}
}
/**
* @see AbstractConverter#createLangAltProperty(String, String, String)
*/
protected void createLangAltProperty(Property metadataProperty, String ns, String propertyName)
throws XMPException {
createLangAltProperty( metadataProperty.getName(), ns, propertyName );
}
/**
* Creates a language alternative property in the x-default language
*
* @param tikaKey
* Key in the Tika metadata map
* @param ns
* namespace the property should be created in
* @param propertyName
* name of the property
* @throws XMPException
* if the property could not be created
*/
protected void createLangAltProperty(String tikaKey, String ns, String propertyName)
throws XMPException {
String value = metadata.get( tikaKey );
if (value != null && value.length() > 0) {
meta.setLocalizedText( ns, propertyName, null, XMPConst.X_DEFAULT, value );
}
}
protected void createArrayProperty(Property metadataProperty, String nsDc,
String arrayProperty, int arrayType) throws XMPException {
createArrayProperty( metadataProperty.getName(), nsDc, arrayProperty, arrayType );
}
/**
* Creates an array property from a list of values.
*
* @param tikaKey
* Key in the Tika metadata map
* @param ns
* namespace the property should be created in
* @param propertyName
* name of the property
* @param arrayType
* depicts which kind of array shall be created
* @throws XMPException
* if the property could not be created
*/
protected void createArrayProperty(String tikaKey, String ns, String propertyName, int arrayType)
throws XMPException {
String[] values = metadata.getValues( tikaKey );
if (values != null) {
meta.setProperty( ns, propertyName, null, new PropertyOptions( arrayType ) );
for (String value : values) {
meta.appendArrayItem( ns, propertyName, value );
}
}
}
protected void createCommaSeparatedArray(Property metadataProperty, String nsDc,
String arrayProperty, int arrayType) throws XMPException {
createCommaSeparatedArray( metadataProperty.getName(), nsDc, arrayProperty, arrayType );
}
/**
* Creates an array property from a comma separated list.
*
* @param tikaKey
* Key in the Tika metadata map
* @param ns
* namespace the property should be created in
* @param propertyName
* name of the property
* @param arrayType
* depicts which kind of array shall be created
* @throws XMPException
* if the property could not be created
*/
protected void createCommaSeparatedArray(String tikaKey, String ns, String propertyName,
int arrayType) throws XMPException {
String value = metadata.get( tikaKey );
if (value != null && value.length() > 0) {
XMPUtils.separateArrayItems( meta, ns, propertyName, value, new PropertyOptions(
arrayType ), false );
}
}
}