spring jdbc踩坑日记，new JdbcTemplate 为null导致UserDao一直为null

  private DataSource datasource;    private JdbcTemplate jdbcTemplate ;    //设置注入    public void setdatasource(DataSource ds) {        this.datasource = ds;        System.out.println("xxxxxxxxxxxxxxxxx");        System.out.println(ds);        this.jdbcTemplate  = new JdbcTemplate(datasource);    }

 private DataSource datasource;    private JdbcTemplate jdbcTemplate ;    //设置注入    public void setDataSource(DataSource ds) {        this.datasource = ds;        System.out.println("xxxxxxxxxxxxxxxxx");        System.out.println(ds);        this.jdbcTemplate  = new JdbcTemplate(datasource);    }