mysql獲取返回的主鍵

因爲線程安全問題所以得用這方法獲得主鍵Id

public class key {
     //獲取主鍵第一種
      @Test
      //select LAST_INSERT_ID()

    //這是第二種
      public void insert(){

          Connection cn = JDBCU.getConnection();
          String sql ="insert into student set sname='ss',sage="+15;
          try {
            PreparedStatement pst = cn.prepareStatement(sql,Statement.RETURN_GENERATED_KEYS);
              pst.executeUpdate();
              ResultSet rs = pst.getGeneratedKeys();
              while(rs.next()){
                  System.out.println(rs.getObject(1));
              }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
      }
}