/*
* Copyright 1999-2015 dangdang.com.
* <p>
* 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.
* </p>
*/
package com.dangdang.ddframe.rdb.sharding.router.database;
import com.dangdang.ddframe.rdb.sharding.api.ShardingValue;
import com.dangdang.ddframe.rdb.sharding.api.rule.DataSourceRule;
import com.dangdang.ddframe.rdb.sharding.api.strategy.database.DatabaseShardingStrategy;
import com.dangdang.ddframe.rdb.sharding.hint.HintManagerHolder;
import com.dangdang.ddframe.rdb.sharding.hint.ShardingKey;
import com.dangdang.ddframe.rdb.sharding.parser.result.router.SQLStatementType;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import java.util.Collection;
import java.util.Collections;
/**
* 库路由.
*
* @author gaohongtao
*/
@RequiredArgsConstructor
@Slf4j
public class DatabaseRouter {
private final DataSourceRule dataSourceRule;
private final DatabaseShardingStrategy databaseShardingStrategy;
private final SQLStatementType sqlStatementType;
/**
* 根据Hint路由到库.
*
* @return 库路由结果
*/
public DatabaseRoutingResult route() {
Optional<ShardingValue<?>> shardingValueOptional = HintManagerHolder.getDatabaseShardingValue(new ShardingKey(HintManagerHolder.DB_TABLE_NAME, HintManagerHolder.DB_COLUMN_NAME));
Preconditions.checkState(shardingValueOptional.isPresent());
log.debug("Before database sharding only db:{} sharding values: {}", dataSourceRule.getDataSourceNames(), shardingValueOptional.get());
Collection<String> routedResult = databaseShardingStrategy
.doStaticSharding(sqlStatementType, dataSourceRule.getDataSourceNames(), Collections.<ShardingValue<?>>singleton(shardingValueOptional.get()));
Preconditions.checkState(!routedResult.isEmpty(), "no database route info");
log.debug("After database sharding only result: {}", routedResult);
return new DatabaseRoutingResult(routedResult);
}
}