/*
* 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.ivory.entity.parser;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.util.List;
import javax.xml.bind.Unmarshaller;
import org.apache.ivory.IvoryException;
import org.apache.ivory.Pair;
import org.apache.ivory.entity.store.ConfigurationStore;
import org.apache.ivory.entity.v0.Entity;
import org.apache.ivory.entity.v0.EntityType;
import org.apache.log4j.Logger;
/**
*
* Generic Abstract Entity Parser, the concrete FEED, PROCESS and CLUSTER
* Should extend this parser to implement specific parsing.
*
* @param <T>
*/
public abstract class EntityParser<T extends Entity> {
private static final Logger LOG = Logger.getLogger(EntityParser.class);
private final EntityType entityType;
/**
* Constructor
*
* @param entityType
* - can be FEED or PROCESS
*/
protected EntityParser(EntityType entityType) {
this.entityType = entityType;
}
public EntityType getEntityType() {
return this.entityType;
}
/**
* Parses a sent XML and validates it using JAXB.
*
* @param xmlString
* - Entity XML
* @return Entity - JAVA Object
* @throws IvoryException
*/
public Entity parseAndValidate(String xmlString) throws IvoryException {
InputStream inputStream = new ByteArrayInputStream(xmlString.getBytes());
Entity entity = parseAndValidate(inputStream);
return entity;
}
/**
* Parses xml stream
*
* @param xmlStream
* @return entity
* @throws IvoryException
*/
public T parse(InputStream xmlStream) throws IvoryException {
try {
// parse against schema
Unmarshaller unmarshaller = entityType.getUnmarshaller();
T entity = (T) unmarshaller.unmarshal(xmlStream);
LOG.info("Parsed Entity: " + entity.getName());
return entity;
} catch(Exception e) {
throw new IvoryException(e);
}
}
public T parseAndValidate(InputStream xmlStream) throws IvoryException {
T entity = parse(xmlStream);
validate(entity);
return entity;
}
protected void validateEntityExists(EntityType type, String name) throws IvoryException {
if(ConfigurationStore.get().get(type, name) == null)
throw new ValidationException("Referenced " + type + " " + name + " is not registered");
}
protected void validateEntitiesExist(List<Pair<EntityType, String>> entities) throws IvoryException {
if(entities != null) {
for(Pair<EntityType, String> entity:entities) {
validateEntityExists(entity.first, entity.second);
}
}
}
public abstract void validate(T entity) throws IvoryException;
}