Java基于jdbc连接mysql数据库操作示例

import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;public class MySQLDemo {  private Connection conn = null;  private Statement stmt = null;  private ResultSet rs = null;  private String driverclass = "com.mysql.jdbc.Driver";  private String url = "jdbc:mysql://localhost:3306/mydb";  private String user = "root";  private String password = "111111";  public MySQLDemo() {    try {      Class.forName(driverclass).newInstance(); // 加载驱动程序    } catch (InstantiationException e) {      // TODO Auto-generated catch block      e.printStackTrace();    } catch (IllegalAccessException e) {      // TODO Auto-generated catch block      e.printStackTrace();    } catch (ClassNotFoundException e1) {      // TODO Auto-generated catch block      System.out.println("class not found");    }    try {      conn = DriverManager.getConnection(url, user, password); // 获得Connection对象    } catch (Exception e) {      System.out.println("Connect failed!");    }  }  public void selectMethod(String sql) {    System.out.println("id title");    try {      stmt = conn.createStatement(); // 获得Statement对象      rs = stmt.executeQuery(sql); // 执行SQL语句，并返回ResultSet类型的结果      while (rs.next()) {        String        String name = rs.getString("name");        System.out.println(title + " " + name);      }    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();    }  }  public void closeDB() throws SQLException {    if (rs != null)      rs.close();    if (stmt != null)      stmt.close(); // 关闭Statement对象    if (conn != null) // 关闭Connection对象      conn.close();  }  public static void main(String args[]) {    MySQLDemo demo = new MySQLDemo();    demo.selectMethod("select * from test");  }}