org.apache.hadoop.sqoop.manager.MySQLManager.java Source code

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Here is the source code for org.apache.hadoop.sqoop.manager.MySQLManager.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.hadoop.sqoop.manager;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.apache.hadoop.sqoop.ImportOptions;

/**
 * Manages connections to MySQL databases
 * 
 *
 */
public class MySQLManager extends GenericJdbcManager {

    public static final Log LOG = LogFactory.getLog(MySQLManager.class.getName());

    // driver class to ensure is loaded when making db connection.
    private static final String DRIVER_CLASS = "com.mysql.jdbc.Driver";

    public MySQLManager(final ImportOptions opts) {
        super(DRIVER_CLASS, opts);

        String connectString = opts.getConnectString();
        if (null != connectString && connectString.indexOf("//localhost") != -1) {
            // if we're not doing a remote connection, they should have a LocalMySQLManager.
            LOG.warn("It looks like you are importing from mysql on localhost.");
            LOG.warn("This transfer can be faster! Use the --local option to exercise a");
            LOG.warn("MySQL-specific fast path.");
        }
    }

    protected MySQLManager(final ImportOptions opts, boolean ignored) {
        // constructor used by subclasses to avoid the --local warning.
        super(DRIVER_CLASS, opts);
    }

    @Override
    public String[] listDatabases() {
        // TODO(aaron): Add an automated unit test for this.

        ResultSet results = execute("SHOW DATABASES");
        if (null == results) {
            return null;
        }

        try {
            ArrayList<String> databases = new ArrayList<String>();
            while (results.next()) {
                String dbName = results.getString(1);
                databases.add(dbName);
            }

            return databases.toArray(new String[0]);
        } catch (SQLException sqlException) {
            LOG.error("Error reading from database: " + sqlException.toString());
            return null;
        }
    }
}