morphy.utils.john.DatabaseConnection.java Source code

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Here is the source code for morphy.utils.john.DatabaseConnection.java

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/*
 *   Morphy Open Source Chess Server
 *   Copyright (C) 2008-2010  http://code.google.com/p/morphy-chess-server/
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *  
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package morphy.utils.john;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

import morphy.Morphy;

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

public class DatabaseConnection {
    protected static final Log LOG = LogFactory.getLog(DatabaseConnection.class);

    private enum DBType {
        MySQL, Derby;
    }

    private DBType type;
    private Connection c;

    public DatabaseConnection() {
        this("localhost", "morphyics", "root", "abcdef");
    }

    public DatabaseConnection(String address, String db, String username, String password) {
        try {
            DBType type = DBType.MySQL;
            this.type = type;

            String driver = "";
            if (type == DBType.MySQL)
                driver = "com.mysql.jdbc.Driver";
            if (type == DBType.Derby)
                driver = "org.apache.derby.jdbc.EmbeddedDriver";
            Class.forName(driver).newInstance();

            String connectionString = "";
            if (type == DBType.MySQL)
                connectionString = "jdbc:mysql://" + address + "/" + db + "?user=" + username + "&password="
                        + password + "";
            if (type == DBType.Derby)
                connectionString = "jdbc:derby:MorphyICSDB;";
            Connection conn = DriverManager.getConnection(connectionString);

            this.c = conn;
        } catch (Exception e) {
            if (LOG.isErrorEnabled()) {
                LOG.error(e);
            }
        }
    }

    /**
     * 
     * @return
     * @throws SQLException 
     */
    public Statement getStatement() throws SQLException {
        return c.createStatement();
    }

    public Connection getConnection() {
        return c;
    }

    public java.sql.ResultSet executeQueryWithRS(String query) {
        try {
            if (LOG.isInfoEnabled()) {
                LOG.info("Executed query: " + query);
            }
            Statement s = getConnection().createStatement();
            s.execute(query);
            return s.getResultSet();
        } catch (SQLException se) {
            Morphy.getInstance().onError(se);
            return null;
        }
    }

    /**
     * Shorthand for getConnection().getStatement().execute(query).
     * You can NOT retrieve ResultSets using this method, so they can only be INSERTs, etc.
     */
    public boolean executeQuery(String query) {
        try {
            if (LOG.isInfoEnabled()) {
                LOG.info("Executed query: " + query);
            }
            getConnection().createStatement().execute(query);
            return true;
        } catch (SQLException se) {
            if (LOG.isErrorEnabled()) {
                LOG.error(se);
                se.printStackTrace(System.err);
            }
            return false;
        }
    }

    public String[] getArray(java.sql.ResultSet r, int columnIndex) {
        try {
            if (columnIndex == 0)
                columnIndex = 1;

            java.util.List<String> arr = new java.util.ArrayList<String>();
            while (r.next()) {
                arr.add(r.getString(columnIndex));
            }
            return arr.toArray(new String[arr.size()]);
        } catch (SQLException e) {
            e.printStackTrace(System.err);
        }
        return null;
    }

    public void closeConnection() {
        if (LOG.isInfoEnabled()) {
            LOG.info("closeConnection() called");
        }

        try {
            if (type == DBType.Derby)
                DriverManager.getConnection("jdbc:derby:;shutdown=true");
        } catch (Exception e) {
            // shutting down derby always throws an exception, even if sucessful.
            if (LOG.isInfoEnabled()) {
                LOG.info("Derby engine shutdown successful.");
            }
        }

        try {
            if (type == DBType.MySQL) {
                c.close();
            }
        } catch (SQLException e) {
            if (LOG.isErrorEnabled()) {
                LOG.error(e);
            }
        }
    }
}