/*
* 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 com.facebook.presto.spi;
/**
* A TableIdentity keeps all the information needed to determine if a table
* has changed.
* <p>
* The TableIdentity is saved as serialized bytes.
* <p>
* TableIdentity can be used to ensure that the tables used in view definition
* have not changed (i.e. dropped and added back again) since the view was created.
* However, TableIdentity can be the same after a table is renamed.
*/
public interface TableIdentity
{
/**
* Serialize the table identity in a manner which is backwards compatible across releases.
*/
byte[] serialize();
/**
* Compare the identities of tables, even for deserialized instances from different releases.
*/
boolean equals(Object o);
/**
* Must be implemented to properly compare the equality of TableIdentity.
*/
int hashCode();
}