/*
* Copyright 2011 VZ Netzwerke Ltd
* Copyright 2014 devbliss GmbH
*
* 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.mongojack.internal.util;
import java.io.IOException;
import org.mongojack.internal.object.BsonObjectGenerator;
import org.mongojack.internal.object.BsonObjectTraversingParser;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.mongodb.MongoException;
/**
* Handler for ids. Converts them between the objects type and the database type
*
* @author James Roper
* @since 1.0
*/
public interface IdHandler<K, D> {
/**
* Convert the given database id to the java objects id
*
* @param dbId
* The database id to convert from
* @return The converted id
*/
K fromDbId(D dbId);
/**
* Convert the given java object id to the databases id
*
* @param id
* The java object id to convert from
* @return The converted database id
*/
D toDbId(K id);
public static class NoopIdHandler<K> implements IdHandler<K, K> {
@Override
public K fromDbId(K dbId) {
return dbId;
}
@Override
public K toDbId(K id) {
return id;
}
}
public static class JacksonIdHandler<K, D> implements IdHandler<K, D> {
private final JsonSerializer<K> jsonSerializer;
private final JsonDeserializer<K> jsonDeserializer;
private final ObjectMapper objectMapper;
public JacksonIdHandler(JsonSerializer<K> jsonSerializer,
JsonDeserializer<K> jsonDeserializer, ObjectMapper objectMapper) {
this.jsonSerializer = jsonSerializer;
this.jsonDeserializer = jsonDeserializer;
this.objectMapper = objectMapper;
}
/**
* Convert the given database id to the java objects id
*
* @param dbId
* The database id to convert from
* @return The converted id
*/
@Override
public K fromDbId(D dbId) {
try {
return jsonDeserializer
.deserialize(new BsonObjectTraversingParser(null, dbId,
objectMapper), null);
} catch (IOException e) {
throw new MongoException("Error deserializing ID", e);
}
}
/**
* Convert the given java object id to the databases id
*
* @param id
* The java object id to convert from
* @return The converted database id
*/
@Override
public D toDbId(K id) {
BsonObjectGenerator generator = new BsonObjectGenerator();
try {
jsonSerializer.serialize(id, generator, null);
} catch (IOException e) {
throw new MongoException("Error serializing ID", e);
}
return (D) generator.getValue();
}
}
}