azkaban.db.DatabaseOperatorImpl.java Source code

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Here is the source code for azkaban.db.DatabaseOperatorImpl.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 org.apache.commons.dbutils.DbUtils;
import org.apache.log4j.Logger;

import java.sql.SQLException;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.ResultSetHandler;
import com.google.inject.Inject;

import static java.util.Objects.*;

/**
 * Implement AZ DB related operations. This class is thread safe.
 */
public class DatabaseOperatorImpl implements DatabaseOperator {

    private static final Logger logger = Logger.getLogger(DatabaseOperatorImpl.class);

    private final QueryRunner queryRunner;

    /**
     * Note: this queryRunner should include a concrete {@link AzkabanDataSource} inside.
     *
     * @param queryRunner
     */
    @Inject
    public DatabaseOperatorImpl(QueryRunner queryRunner) {
        requireNonNull(queryRunner.getDataSource(), "data source must not be null.");
        this.queryRunner = queryRunner;
    }

    /**
     * query method Implementation. it will call {@link AzkabanDataSource#getConnection()} inside queryrunner.query.
     */
    @Override
    public <T> T query(String baseQuery, ResultSetHandler<T> resultHandler, Object... params) throws SQLException {
        try {
            return queryRunner.query(baseQuery, resultHandler, params);
        } catch (SQLException ex) {
            // todo kunkun-tang: Retry logics should be implemented here.
            logger.error("query failed", ex);
            throw ex;
        }
    }

    /**
     * transaction method Implementation.
     *
     */
    @Override
    public <T> T transaction(SQLTransaction<T> operations) throws SQLException {
        Connection conn = null;
        try {
            conn = queryRunner.getDataSource().getConnection();
            conn.setAutoCommit(false);
            DatabaseTransOperator transOperator = new DatabaseTransOperatorImpl(queryRunner, conn);
            T res = operations.execute(transOperator);
            conn.commit();
            return res;
        } catch (SQLException ex) {
            // todo kunkun-tang: Retry logics should be implemented here.
            logger.error("transaction failed", ex);
            throw ex;
        } finally {
            DbUtils.closeQuietly(conn);
        }
    }

    /**
     * update implementation. it will call {@link AzkabanDataSource#getConnection()} inside queryrunner.update.
     *
     * @param updateClause sql statements to execute
     * @param params Initialize the PreparedStatement's IN parameters
     * @return the number of rows being affected by update
     * @throws SQLException
     */
    @Override
    public int update(String updateClause, Object... params) throws SQLException {
        try {
            return queryRunner.update(updateClause, params);
        } catch (SQLException ex) {
            // todo kunkun-tang: Retry logics should be implemented here.
            logger.error("update failed", ex);
            throw ex;
        }
    }
}