Get Column Information

package example.column;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
 
public class Main1 {
 
    public static void main(String[] args) throws Exception {
	Connection conn = getMySqlConnection();
	System.out.println("Got Connection.");
 
	ResultSet rsColumns = null;
	DatabaseMetaData meta = conn.getMetaData();
	rsColumns = meta.getColumns(null, "%", "code", "%");
 
	while (rsColumns.next()) {
	    String columnType = rsColumns.getString("TYPE_NAME");
	    String columnName = rsColumns.getString("COLUMN_NAME");
	    int size = rsColumns.getInt("COLUMN_SIZE");
	    int nullable = rsColumns.getInt("NULLABLE");
	    int position = rsColumns.getInt("ORDINAL_POSITION");
 
	    System.out.println("column name=" + columnName);
	    System.out.println("type=" + columnType);
	    System.out.println("size=" + size);
	    if (nullable == DatabaseMetaData.columnNullable) {
		System.out.println("nullable is true");
	    } else {
		System.out.println("nullable is false");
	    }
	    System.out.println("position" + position);
	}
 
	conn.close();
    }
 
    private static Connection getHSQLConnection() throws Exception {
	Class.forName("org.hsqldb.jdbcDriver");
	System.out.println("Driver Loaded.");
	String url = "jdbc:hsqldb:data/tutorial";
	return DriverManager.getConnection(url, "sa", "");
    }
 
    public static Connection getMySqlConnection() throws Exception {
	String driver = "org.gjt.mm.mysql.Driver";
	String url = "jdbc:mysql://localhost/demo2s";
	String username = "oost";
	String password = "oost";
 
	Class.forName(driver);
	Connection conn = DriverManager.getConnection(url, username, password);
	return conn;
    }
 
    public static Connection getOracleConnection() throws Exception {
	String driver = "oracle.jdbc.driver.OracleDriver";
	String url = "jdbc:oracle:thin:@localhost:1521:caspian";
	String username = "mp";
	String password = "mp2";
 
	Class.forName(driver); // load Oracle driver
	Connection conn = DriverManager.getConnection(url, username, password);
	return conn;
    }
 
}