Getting Connected for the First Time with JDBC

Question

Hello everyone. I am trying to make my first database connection to a mysql database with Java. I am using jdk 1.5.0, MySQL 4.1.11 nt, and I think I have the freshly downloaded driver C:\jdk1.5.0\jre\lib\ext\mysql-connector-java-3.0.16-ga-bin.jar" installed in the right spot. When I try to run the following code...
package dbfinder;
import java.sql.*;
import javax.sql.*;
import com.sun.rowset.JdbcRowSetImpl;
import javax.sql.rowset.JdbcRowSet;
import java.sql.ResultSetMetaData;
* <p>Title: </p>
* <p>Description: </p>
* <p>Copyright: Copyright (c) 2005</p>
* <p>Company: </p>
* @author not attributable
* @version 1.0
public class DatabaseConnector {
public DatabaseConnector() {
public static void main(String args[]){
Connection connection;
Statement statement;
// ResultSet resultSet;
// ResultSetMetaData metaData;
String DATABASE_DRIVER = "com.mysql.jdbc.Driver";
String DATABASE_URL = "jdbc:mysql://localhost/state_crime";
String USER = "cis695d";
String PASSWORD = "cis695d";
JdbcRowSet rowSet = new JdbcRowSetImpl();
try {
Class.forName(DATABASE_DRIVER); // load database driver
System.out.println("class loaded");
rowSet.setUrl("DATABASE_URL");
rowSet.setUsername(USER);
rowSet.setPassword(PASSWORD);
rowSet.setCommand("Select * FROM state_crime_rates");
rowSet.execute();
ResultSetMetaData metaData = rowSet.getMetaData();
int numberOfColumns;
numberOfColumns = metaData.getColumnCount();
System.out.println(numberOfColumns);
} catch(SQLException sqlException){
sqlException.printStackTrace();
System.exit(1);
catch(ClassNotFoundException classNotFound){
classNotFound.printStackTrace();
System.exit(1);
I get the following exception...
java.sql.SQLException: No suitable driver
     at java.sql.DriverManager.getConnection(DriverManager.java:545)
     at java.sql.DriverManager.getConnection(DriverManager.java:171)
     at com.sun.rowset.JdbcRowSetImpl.connect(JdbcRowSetImpl.java:618)
     at com.sun.rowset.JdbcRowSetImpl.prepare(JdbcRowSetImpl.java:630)
     at com.sun.rowset.JdbcRowSetImpl.execute(JdbcRowSetImpl.java:526)
     at dbfinder.DatabaseConnector.main(DatabaseConnector.java:44)
Does anyone have any ideas? Is it my code? Is there a different driver I should use? Any help would be greatly appreciated.

Answer 1

Hello everyone. I am trying to make my first
database connection to a mysql database with Java. I
am using jdk 1.5.0, MySQL 4.1.11 nt, and I think I
have the freshly downloaded driver
C:\jdk1.5.0\jre\lib\ext\mysql-connector-java-3.0.16-ga
-bin.jar" installed in the right spot. You shouldn't be putting that JAR in jre/lib/ext, even if you've found some docs to tell you to do it. Only language extensions (e.g., packages that begin w/javax) belong there.
I get the following exception...
java.sql.SQLException: No suitable driver
Does anyone have any ideas? Is it my code? Is there
a different driver I should use? Any help would be
greatly appreciated.The driver is correct. The class loader found it, even though I think you should use the -classpath option to find the JAR.
It's your code.
What are you doing with all that RowSet stuff?
This works. Study it:
import java.sql.*;
import java.util.*;
* Command line app that allows a user to connect with a database and
* execute any valid SQL against it
public class DataConnection
    public static final String DEFAULT_DRIVER   = "sun.jdbc.odbc.JdbcOdbcDriver";
    public static final String DEFAULT_URL      = "jdbc:odbc:DRIVER={Microsoft Access Driver (*.mdb)};DBQ=c:\\Edu\\Java\\Forum\\DataConnection.mdb";
    public static final String DEFAULT_USERNAME = "admin";
    public static final String DEFAULT_PASSWORD = "";
    public static final String DEFAULT_DRIVER   = "com.mysql.jdbc.Driver";
    public static final String DEFAULT_URL      = "jdbc:mysql://localhost:3306/hibernate";
    public static final String DEFAULT_USERNAME = "admin";
    public static final String DEFAULT_PASSWORD = "";
    /** Database connection */
    private Connection connection;
     * Driver for the DataConnection
     * @param command line arguments
     * <ol start='0'>
     * <li>SQL query string</li>
     * <li>JDBC driver class</li>
     * <li>database URL</li>
     * <li>username</li>
     * <li>password</li>
     * </ol>
    public static void main(String [] args)
        DataConnection db = null;
        try
            if (args.length > 0)
                String sql      = args[0];
                String driver   = ((args.length > 1) ? args[1] : DEFAULT_DRIVER);
                String url      = ((args.length > 2) ? args[2] : DEFAULT_URL);
                String username = ((args.length > 3) ? args[3] : DEFAULT_USERNAME);
                String password = ((args.length > 4) ? args[4] : DEFAULT_PASSWORD);
                System.out.println("sql     : " + sql);
                System.out.println("driver  : " + driver);
                System.out.println("url     : " + url);
                System.out.println("username: " + username);
                System.out.println("password: " + password);
                db = new DataConnection(driver, url, username, password);
                System.out.println("Connection established");
                Object result = db.executeSQL(sql);
                System.out.println(result);
            else
                System.out.println("Usage: db.DataConnection <sql> <driver> <url> <username> <password>");
        catch (SQLException e)
            System.err.println("SQL error: " + e.getErrorCode());
            System.err.println("SQL state: " + e.getSQLState());
            e.printStackTrace(System.err);
        catch (Exception e)
            e.printStackTrace(System.err);
        finally
            if (db != null)
                db.close();
            db = null;
     * Create a DataConnection
     * @throws SQLException if the database connection fails
     * @throws ClassNotFoundException if the driver class can't be loaded
    public DataConnection() throws SQLException,ClassNotFoundException
        this(DEFAULT_DRIVER, DEFAULT_URL, DEFAULT_USERNAME, DEFAULT_PASSWORD);
     * Create a DataConnection
     * @throws SQLException if the database connection fails
     * @throws ClassNotFoundException if the driver class can't be loaded
    public DataConnection(final String driver,
                          final String url,
                          final String username,
                          final String password)
        throws SQLException,ClassNotFoundException
        Class.forName(driver);
        this.connection = DriverManager.getConnection(url, username, password);
     * Get Driver properties
     * @param database URL
     * @return list of driver properties
     * @throws SQLException if the query fails
    public List getDriverProperties(final String url)
        throws SQLException
        List driverProperties   = new ArrayList();
        Driver driver           = DriverManager.getDriver(url);
        if (driver != null)
            DriverPropertyInfo[] info = driver.getPropertyInfo(url, null);
            if (info != null)
                driverProperties    = Arrays.asList(info);
        return driverProperties;
     * Clean up the connection
    public void close()
        close(this.connection);
     * Execute ANY SQL statement
     * @param SQL statement to execute
     * @returns list of row values if a ResultSet is returned,
     * OR an altered row count object if not
     * @throws SQLException if the query fails
    public Object executeSQL(final String sql) throws SQLException
        Object returnValue;
        Statement statement = null;
        ResultSet rs = null;
        try
            statement = this.connection.createStatement();
            boolean hasResultSet    = statement.execute(sql);
            if (hasResultSet)
                rs                      = statement.getResultSet();
                ResultSetMetaData meta  = rs.getMetaData();
                int numColumns          = meta.getColumnCount();
                List rows               = new ArrayList();
                while (rs.next())
                    Map thisRow = new LinkedHashMap();
                    for (int i = 1; i <= numColumns; ++i)
                        String columnName   = meta.getColumnName(i);
                        Object value        = rs.getObject(columnName);
                        thisRow.put(columnName, value);
                    rows.add(thisRow);
                returnValue = rows;
        else
            int updateCount = statement.getUpdateCount();
            returnValue     = new Integer(updateCount);
        finally
            close(rs);
            close(statement);
        return returnValue;
     * Close a database connection
     * @param connection to close
    public static final void close(Connection connection)
        try
            if (connection != null)
                connection.close();
                connection = null;
        catch (SQLException e)
            e.printStackTrace();
     * Close a statement
     * @param statement to close
    public static final void close(Statement statement)
        try
            if (statement != null)
                statement.close();
                statement = null;
        catch (SQLException e)
            e.printStackTrace();
     * Close a result set
     * @param rs to close
    public static final void close(ResultSet rs)
        try
            if (rs != null)
                rs.close();
                rs = null;
        catch (SQLException e)
            e.printStackTrace();
     * Close a database connection and statement
     * @param connection to close
     * @param statement to close
    public static final void close(Connection connection, Statement statement)
        close(statement);
        close(connection);
     * Close a database connection, statement, and result set
     * @param connection to close
     * @param statement to close
     * @param rs to close
    public static final void close(Connection connection,
                                   Statement statement,
                                   ResultSet rs)
        close(rs);
        close(statement);
        close(connection);
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