使用JDBC从数据库中查询数据的方法

@Test
  public void testResultSet(){
    //获取id=2的customers数据表的记录，并打印
    Connection connection = null;
    Statement statement = null;
    ResultSet rs = null;
    try {
      //1.获取Connection
      connection = JDBCTools.getConnection();
      //2.获取Statement
      statement = connection.createStatement();
      //3.准备Sql
      String sql = "SELECT * FROM CUSTOMERS WHERE ID=2";
      //4.执行查询，得到ResultSet
      rs = statement.executeQuery(sql);
      //5.处理ResultSet
      while(rs.next()){
        //rs.get+数据库中对应的类型+(数据库中对应的列别名)
        int id = rs.getInt("ID");
        String name = rs.getString("name");
        String email = rs.getString("email");
        Date birth = rs.getDate("birth");
        
        System.out.println(id);
        System.out.println(name);
        System.out.println(email);
        System.out.println(birth);
      }
    } catch (Exception e) {
      e.printStackTrace();
    }finally{
      //6.关闭数据库相应的资源
      JDBCTools.release(rs, statement, connection);
    }
  }