org.dizitart.no2.store.NitriteStore Maven / Gradle / Ivy
/*
*
* Copyright 2017-2018 Nitrite author or authors.
*
* 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.dizitart.no2.store;
import org.dizitart.no2.meta.Attributes;
import java.util.Set;
/**
* Represents a persistent storage for Nitrite database.
*
* @since 1.0
* @author Anindya Chatterjee
* @see NitriteMVStore
*/
public interface NitriteStore {
/**
* Gets the set of all map names.
*
* @return the set of names.
*/
Set getMapNames();
/**
* Checks whether there are any unsaved changes.
*
* @return `true` if there are any changes; `false` otherwise.
*/
boolean hasUnsavedChanges();
/**
* Checks whether this store is closed for further modification.
*
* @return `true` if closed; `false` otherwise.
*/
boolean isClosed();
/**
* Compacts the store by moving all chunks next to each other.
*/
void compact();
/**
* Commits the changes. For persistent stores, it also writes
* changes to disk. It does nothing if there are no unsaved changes.
*/
void commit();
/**
* Closes the file and the store. Unsaved changes are written to disk first.
*/
void close();
/**
* Closes the file and the store, without writing anything. This method
* ignores all errors.
*/
void closeImmediately();
/**
* Checks whether a given map exists in the store.
*
* @param mapName the map name
* @return `true` if it exists; `false` otherwise.
*/
boolean hasMap(String mapName);
/**
* Opens a {@link NitriteMap} with the default settings. The map is
* automatically create if it does not yet exist. If a map with this
* name is already open, this map is returned.
*
* @param the key type
* @param the value type
* @param mapName the map name
* @return the map.
*/
NitriteMap openMap(String mapName);
/**
* Removes a map from the store.
*
* @param the key type
* @param the value type
* @param nitriteMap the map to remove.
*/
void removeMap(NitriteMap nitriteMap);
/**
* Gets the metadata of all {@link NitriteMap}s.
*
* @return meta data of all maps.
* */
NitriteMap metaMap();
}