/**
* 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.bookkeeper.metastore;
import java.util.Collections;
import java.util.Set;
import org.apache.bookkeeper.versioning.Version;
import org.apache.bookkeeper.versioning.Versioned;
public interface MetastoreTable {
// select all fields when reading or scanning entries
public static final Set<String> ALL_FIELDS = null;
// select non fields to return when reading/scanning entries
public static final Set<String> NON_FIELDS = Collections.emptySet();
/**
* Get table name.
*
* @return table name
*/
public String getName();
/**
* Get all fields of a key.
*
* <p>
* Return Code:<ul>
* <li>{@link MSException.Code.OK}: success returning the key</li>
* <li>{@link MSException.Code.NoKey}: no key found</li>
* <li>{@link MSException.Code.IllegalOp}/{@link MSException.Code.ServiceDown}: other issues</li>
* </ul></p>
*
* @param key
* Key Name
* @param cb
* Callback to return all fields of the key
* @param ctx
* Callback context
*/
public void get(String key, MetastoreCallback<Versioned<Value>> cb, Object ctx);
/**
* Get all fields of a key.
*
* <p>
* Return Code:<ul>
* <li>{@link MSException.Code.OK}: success returning the key</li>
* <li>{@link MSException.Code.NoKey}: no key found</li>
* <li>{@link MSException.Code.IllegalOp}/{@link MSException.Code.ServiceDown}: other issues</li>
* </ul></p>
*
* @param key
* Key Name
* @param watcher
* Watcher object to receive notifications
* @param cb
* Callback to return all fields of the key
* @param ctx
* Callback context
*/
public void get(String key, MetastoreWatcher watcher, MetastoreCallback<Versioned<Value>> cb, Object ctx);
/**
* Get specified fields of a key.
*
* <p>
* Return Code:<ul>
* <li>{@link MSException.Code.OK}: success returning the key</li>
* <li>{@link MSException.Code.NoKey}: no key found</li>
* <li>{@link MSException.Code.IllegalOp}/{@link MSException.Code.ServiceDown}: other issues</li>
* </ul></p>
*
* @param key
* Key Name
* @param fields
* Fields to return
* @param cb
* Callback to return specified fields of the key
* @param ctx
* Callback context
*/
public void get(String key, Set<String> fields,
MetastoreCallback<Versioned<Value>> cb, Object ctx);
/**
* Update a key according to its version.
*
* <p>
* Return Code:<ul>
* <li>{@link MSException.Code.OK}: success updating the key</li>
* <li>{@link MSException.Code.BadVersion}: failed to update the key due to bad version</li>
* <li>{@link MSException.Code.NoKey}: no key found to update data, if not provided {@link Version.NEW}</li>
* <li>{@link MSException.Code.KeyExists}: entry exists providing {@link Version.NEW}</li>
* <li>{@link MSException.Code.IllegalOp}/{@link MSException.Code.ServiceDown}: other issues</li>
* </ul></p>
*
* The key is updated only when the version matches its current version.
* In particular, if the provided version is:<ul>
* <li>{@link Version.ANY}: update the data without comparing its version.
* <b>Note this usage is not encouraged since it may mess up data consistency.</b></li>
* <li>{@link Version.NEW}: create the entry if it doesn't exist before;
* Otherwise return {@link MSException.Code.KeyExists}.</li>
* </ul>
*
* @param key
* Key Name
* @param value
* Value to update.
* @param version
* Version specified to update.
* @param cb
* Callback to return new version after updated.
* @param ctx
* Callback context
*/
public void put(String key, Value value, Version version, MetastoreCallback<Version> cb, Object ctx);
/**
* Remove a key by its version.
*
* The key is removed only when the version matches its current version.
* If <code>version</code> is {@link Version.ANY}, the key would be removed directly.
*
* <p>
* Return Code:<ul>
* <li>{@link MSException.Code.OK}: success updating the key</li>
* <li>{@link MSException.Code.NoKey}: if the key doesn't exist.</li>
* <li>{@link MSException.Code.BadVersion}: failed to delete the key due to bad version</li>
* <li>{@link MSException.Code.IllegalOp}/{@link MSException.Code.ServiceDown}: other issues</li>
* </ul></p>
*
* @param key
* Key Name.
* @param version
* Version specified to remove.
* @param cb
* Callback to return all fields of the key
* @param ctx
* Callback context
*/
public void remove(String key, Version version,
MetastoreCallback<Void> cb, Object ctx);
/**
* Open a cursor to loop over all the entries of the table,
* which returns all fields for each entry.
* The returned cursor doesn't need to guarantee any order,
* since the underlying might be a hash table or an order table.
*
* @param cb
* Callback to return an opened cursor
* @param ctx
* Callback context
*/
public void openCursor(MetastoreCallback<MetastoreCursor> cb, Object ctx);
/**
* Open a cursor to loop over all the entries of the table,
* which returns the specified <code>fields</code> for each entry.
* The returned cursor doesn't need to guarantee any order,
* since the underlying might be a hash table or an order table.
*
* @param fields
* Fields to select
* @param cb
* Callback to return an opened cursor
* @param ctx
* Callback context
*/
public void openCursor(Set<String> fields,
MetastoreCallback<MetastoreCursor> cb, Object ctx);
/**
* Close the table.
*/
public void close();
}