Java数据库随机显示

Question

private void Label_GenerateMouseClicked(java.awt.event.MouseEvent evt) {                                            
    // TODO add your handling code here:
    try{
        String sql = "select from Account ORDER BY RAND()";
        PreparedStatement st = con.prepareStatement(sql);
        ResultSet rs = st.executeQuery();

        if(rs.next()){
            TextField_Username.setText(rs.getString("EMAIL"));
            TextField_Password.setText(rs.getString("PASSWORD"));
        }
    }catch(Exception e){
        System.out.println("Cannot generate.");
    }
}                                           

这段代码不断捕获错误，但我不明白为什么。我收到错误 java.lang.NullPointerException。请帮忙

Answer 1

NVM 伙计们，我想通了。我没有运行我的连接功能。抱歉给您带来麻烦。