HintSchemaHandler.java

package org.opencloudb.route.handler;

import java.sql.SQLNonTransientException;

import org.apache.log4j.Logger;
import org.opencloudb.MycatSystem;
import org.opencloudb.cache.LayerCachePool;
import org.opencloudb.config.model.SchemaConfig;
import org.opencloudb.config.model.SystemConfig;
import org.opencloudb.net.FrontSession;
import org.opencloudb.route.RouteResultset;
import org.opencloudb.route.RouteStrategy;
import org.opencloudb.route.factory.RouteStrategyFactory;

/**
 * 处理注释中类型为schema 的情况（按照指定schema做路由解析）
 */
public class HintSchemaHandler implements HintHandler {

	private static final Logger LOGGER = Logger
			.getLogger(HintSchemaHandler.class);

	private RouteStrategy routeStrategy;
    
    public HintSchemaHandler() {
		this.routeStrategy = RouteStrategyFactory.getRouteStrategy();
	}
	/**
	 * 从全局的schema列表中查询指定的schema是否存在， 如果存在则替换connection属性中原有的schema，
	 * 如果不存在，则throws SQLNonTransientException，表示指定的schema 不存在
	 * 
	 * @param sysConfig
	 * @param schema
	 * @param sqlType
	 * @param realSQL
	 * @param charset
	 * @param info
	 * @param cachePool
	 * @param hintSQLValue
	 * @return
	 * @throws SQLNonTransientException
	 */
	@Override
	public RouteResultset route(SystemConfig sysConfig, SchemaConfig schema,
			int sqlType, String realSQL, String charset, FrontSession session,
			LayerCachePool cachePool, String hintSQLValue)
			throws SQLNonTransientException {
		schema = MycatSystem.getInstance().getConfig().getSchemas()
				.get(hintSQLValue);
		if (schema != null) {
			RouteResultset rrs = routeStrategy.route(sysConfig, schema,
					sqlType, realSQL, charset, session, cachePool);
			return rrs;
		} else {
			String msg = "can't find schema:" + schema.getName();
			LOGGER.warn(msg);
			throw new SQLNonTransientException(msg);
		}
	}
}