io.telicent.smart.cache.sources.kafka.serializers.GraphDeserializer Maven / Gradle / Ivy
/**
* Copyright (C) Telicent Ltd
*
* 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 io.telicent.smart.cache.sources.kafka.serializers;
import org.apache.jena.graph.Graph;
import org.apache.jena.riot.Lang;
import org.apache.jena.riot.RDFParser;
import org.apache.jena.sparql.graph.GraphFactory;
/**
* A Kafka deserializer that deserializes RDF Graphs represented using Jena's {@link Graph} class
*
* This will use either the default language ({@link Lang#NTRIPLES}, or the language identified by the
* {@code Content-Type} header from the event headers, to try and parse the event key/value as an RDF graph.
*
*/
public class GraphDeserializer extends AbstractRdfDeserializer {
/**
* Creates a new deserializer that defaults to {@link Lang#NTRIPLES}
*/
public GraphDeserializer() {
this(Lang.NTRIPLES);
}
/**
* Creates a new deserializer with the given default language
*
* This is declared as package private so that the default language can only be changed by explicitly deriving a
* sub-class from this implementation, or in unit test cases.
*
*
* @param defaultLang Default language
*/
GraphDeserializer(Lang defaultLang) {
super(defaultLang);
}
@Override
protected Graph deserializeInternal(RDFParser parser) {
Graph g = GraphFactory.createDefaultGraph();
parser.parse(g);
return g;
}
}