/**
* 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.hadoop.hive.metastore.messaging;
/**
* Class representing messages emitted when Metastore operations are done.
* (E.g. Creation and deletion of databases, tables and partitions.)
*/
public abstract class EventMessage {
/**
* Enumeration of all supported types of Metastore operations.
*/
public static enum EventType {
CREATE_DATABASE(MessageFactory.CREATE_DATABASE_EVENT),
DROP_DATABASE(MessageFactory.DROP_DATABASE_EVENT),
CREATE_TABLE(MessageFactory.CREATE_TABLE_EVENT),
DROP_TABLE(MessageFactory.DROP_TABLE_EVENT),
ADD_PARTITION(MessageFactory.ADD_PARTITION_EVENT),
DROP_PARTITION(MessageFactory.DROP_PARTITION_EVENT),
ALTER_TABLE(MessageFactory.ALTER_TABLE_EVENT),
ALTER_PARTITION(MessageFactory.ALTER_PARTITION_EVENT),
INSERT(MessageFactory.INSERT_EVENT),
CREATE_FUNCTION(MessageFactory.CREATE_FUNCTION_EVENT),
DROP_FUNCTION(MessageFactory.DROP_FUNCTION_EVENT),
CREATE_INDEX(MessageFactory.CREATE_INDEX_EVENT),
DROP_INDEX(MessageFactory.DROP_INDEX_EVENT),
ALTER_INDEX(MessageFactory.ALTER_INDEX_EVENT);
private String typeString;
EventType(String typeString) {
this.typeString = typeString;
}
@Override
public String toString() { return typeString; }
}
protected EventType eventType;
protected EventMessage(EventType eventType) {
this.eventType = eventType;
}
public EventType getEventType() {
return eventType;
}
/**
* Getter for HCatalog Server's URL.
* (This is where the event originates from.)
* @return HCatalog Server's URL (String).
*/
public abstract String getServer();
/**
* Getter for the Kerberos principal of the HCatalog service.
* @return HCatalog Service Principal (String).
*/
public abstract String getServicePrincipal();
/**
* Getter for the name of the Database on which the Metastore operation is done.
* @return Database-name (String).
*/
public abstract String getDB();
/**
* Getter for the timestamp associated with the operation.
* @return Timestamp (Long - seconds since epoch).
*/
public abstract Long getTimestamp();
/**
* Class invariant. Checked after construction or deserialization.
*/
public EventMessage checkValid() {
if (getServer() == null || getServicePrincipal() == null)
throw new IllegalStateException("Server-URL/Service-Principal shouldn't be null.");
if (getEventType() == null)
throw new IllegalStateException("Event-type unset.");
if (getDB() == null)
throw new IllegalArgumentException("DB-name unset.");
return this;
}
}