azkaban.db.DatabaseTransOperatorImpl.java Source code

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Here is the source code for azkaban.db.DatabaseTransOperatorImpl.java

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/*
 * Copyright 2017 LinkedIn Corp.
 *
 * 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 azkaban.db;

import java.sql.Connection;
import java.sql.SQLException;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.ResultSetHandler;
import org.apache.commons.dbutils.handlers.ScalarHandler;
import org.apache.log4j.Logger;

/**
 * This class should be only used inside {@link DatabaseOperatorImpl}, then we remove public.
 */
class DatabaseTransOperatorImpl implements DatabaseTransOperator {

    private static final Logger logger = Logger.getLogger(DatabaseTransOperator.class);
    private final Connection conn;
    private final QueryRunner queryRunner;

    public DatabaseTransOperatorImpl(QueryRunner queryRunner, Connection conn) {
        this.conn = conn;
        this.queryRunner = queryRunner;
    }

    /**
     * The ID that was generated is maintained in Mysql server on a per-connection basis.
     * This means that the value returned by the function to a given client is
     * the first AUTO_INCREMENT value generated for most recent statement
     *
     * This value cannot be affected by other callers, even if they generate
     * AUTO_INCREMENT values of their own.
     * @return last insertion ID
     *
     */
    @Override
    public long getLastInsertId() throws SQLException {
        // A default connection: autocommit = true.
        long num = -1;
        try {
            num = ((Number) queryRunner.query(conn, "SELECT LAST_INSERT_ID();", new ScalarHandler<>(1)))
                    .longValue();
        } catch (SQLException ex) {
            logger.error("can not get last insertion ID");
            throw ex;
        }
        return num;
    }

    @Override
    public <T> T query(String querySql, ResultSetHandler<T> resultHandler, Object... params) throws SQLException {
        try {
            return queryRunner.query(conn, querySql, resultHandler, params);
        } catch (SQLException ex) {
            //RETRY Logic should be implemented here if needed.
            throw ex;
        } finally {
            // Note: CAN NOT CLOSE CONNECTION HERE.
        }
    }

    @Override
    public int update(String updateClause, Object... params) throws SQLException {
        try {
            return queryRunner.update(conn, updateClause, params);
        } catch (SQLException ex) {
            //RETRY Logic should be implemented here if needed.
            throw ex;
        } finally {
            // Note: CAN NOT CLOSE CONNECTION HERE.
        }
    }

    @Override
    public Connection getConnection() {
        return conn;
    }
}