ShardMapping.java

/*
  Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved.

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FLOSS License Exception
  <http://www.mysql.com/about/legal/licensing/foss-exception.html>.

  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.

  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with this
  program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA

 */

package com.mysql.fabric;

import java.util.Collections;
import java.util.Set;

/**
 * A shard mapping representing this set of sharded data.
 */
public abstract class ShardMapping {
    private int mappingId;
    private ShardingType shardingType;
    private String globalGroupName;
    protected Set<ShardTable> shardTables;
    protected Set<ShardIndex> shardIndices;

    public ShardMapping(int mappingId, ShardingType shardingType, String globalGroupName, Set<ShardTable> shardTables, Set<ShardIndex> shardIndices) {
        this.mappingId = mappingId;
        this.shardingType = shardingType;
        this.globalGroupName = globalGroupName;
        this.shardTables = shardTables;
        this.shardIndices = shardIndices;
    }

    /**
     * Lookup the server group that stores the given key.
     */
    public String getGroupNameForKey(String key) {
        return getShardIndexForKey(key).getGroupName();
    }

    /**
     * Decide which shard index stores the given key.
     */
    protected abstract ShardIndex getShardIndexForKey(String key);

    /**
     * The ID of this mapping.
     */
    public int getMappingId() {
        return this.mappingId;
    }

    /**
     * The {@link ShardingType} of this mapping.
     */
    public ShardingType getShardingType() {
        return this.shardingType;
    }

    /**
     * The name of the global group for this shard map.
     */
    public String getGlobalGroupName() {
        return this.globalGroupName;
    }

    /**
     * Return the set of tables sharded in this mapping.
     */
    public Set<ShardTable> getShardTables() {
        return Collections.unmodifiableSet(this.shardTables);
    }

    /**
     * Return the set of shards in this mapping.
     */
    public Set<ShardIndex> getShardIndices() {
        return Collections.unmodifiableSet(this.shardIndices);
    }
}