dataaccess.java

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import java.sql.DriverManager;
import java.sql.SQLException;

import com.mysql.jdbc.Connection;
import java.sql.*;

public class DataAccess implements Runnable {

	final static public String dbUrl = "jdbc:MySQL://localhost:3306/cpaths_profiles";

	final static public String driverClass = "com.mysql.jdbc.Driver";

	//final static public String user = "cpaths";

	//final static public String password = "buckin8t0r";
	
	final static public String user = "root";

	final static public String password = "root";

	private static Connection connection;

	public static Connection getConnection() throws SQLException {

		if (connection == null)
			connection = getNewConnection();
		else if (connection.isClosed())
			connection = getNewConnection();
		return connection;
	}

	public static synchronized void refreshConnection() throws SQLException {
		if (connection != null)
			try {
				connection.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		connection = null;
		connection = getNewConnection();
	}

	public static Connection getNewConnection() throws SQLException {
		java.util.Date date = new java.util.Date();
		Connection newConnection = null;
		try {
			Class.forName(driverClass);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
			return null;
		}
		int retry = 0;

		while (newConnection == null)
			try {
				newConnection = (Connection) DriverManager.getConnection(dbUrl,
						user, password);
				newConnection.setConnectTimeout(60000);
				newConnection.setSocketTimeout(300000);
				newConnection.setAutoReconnect(false);
				// newConnection.setInitialTimeout(2);
				// newConnection.setEnableQueryTimeouts(false);
				newConnection.setUseCompression(true);
				newConnection.setTcpRcvBuf(1024000);
				newConnection.setTcpSndBuf(1024000);
				// newConnection.setMaxReconnects(50);
				// newConnection.setTcpKeepAlive(true);
				//newConnection = null;
			} catch (SQLException e) {
				if (retry++ > 30)
					throw e;
				System.out.println("Retrying getNewConnection for " + retry
						+ " times.");
			}
		System.out.println("Establish a database connection spent time ms: "
				+ (new java.util.Date().getTime() - date.getTime()));
		return newConnection;
	}

	public static ResultSet getRS(String sql) throws SQLException {
		PreparedStatement ps = connection.prepareStatement(sql);
		return ps.executeQuery();
	}

	public static int exeSQL(String sql) throws SQLException {
		PreparedStatement ps = connection.prepareStatement(sql);
		return ps.executeUpdate();
	}

	public static void main(String[] args) throws SQLException,
			ClassNotFoundException {

	}

	public void run() {
		try {
			refreshConnection();
		} catch (SQLException e) {
			e.printStackTrace();
		}

	}

}