Java 如何正确转换 jdbc 查询的结果

Question

(Postgres 9.4) 我有一个返回整数 4 的简单查询，然后我捕获该数字并循环遍历 if 语句并返回编辑后的结果。答案应该是 4 分钟，但我一直在 4 周。由于某种原因，这不起作用，例如这是我的代码

   try {
            Connection con = null;
            ResultSet rs;
        con=DB.getConnection();


           // this fire returns as an Integer 4
            PreparedStatement ps =con.prepareStatement("SELECT EXTRACT
(EPOCH FROM(last_reply-created_on)/60):: integer as fire from streams where id=65");
            rs= ps.executeQuery();


            while (rs.next()) {
             // I then put this method through
                System.err.println(difference(rs.getInt("fire")));
            }
            con.close();
            return ok();
        } catch (Exception e) {
            System.err.println(e.getMessage());
        }
    private static String difference(Integer i) {
String id="";
        if(i<60)
        {
         4 is obviously less than 60 but it is not working
            id= i+ " min";
        }
        if(i>=60 && i<1440)
        {
            id=i+ " hrs";
        }
        if(i>=1441 && i<10080)
        {
            id=i+" days";
        }
        else
        {
            id=i+" weeks";
        }
// returns as 4 date
        return id;
    }

我正在使用这个 System.err.println(difference(rs.getInt("fire"))); 来跟踪结果。我怎样才能完成这项工作，或者有更好的方法来实现这一目标吗？

Answer 1

你在 if-else 语句中有一个错误。试试下面的一个

try {
        Connection con = null;
        ResultSet rs;
    con=DB.getConnection();


       // this fire returns as an Integer 4
        PreparedStatement ps =con.prepareStatement("SELECT EXTRACT
(EPOCH FROM(last_reply-created_on)/60):: integer as fire from streams where id=65");
        rs= ps.executeQuery();


        while (rs.next()) {
         // I then put this method through
            System.err.println(difference(rs.getInt("fire")));
        }
        con.close();
        return ok();
    } catch (Exception e) {
        System.err.println(e.getMessage());
    }
private static String difference(Integer i) {
String id="";
    if(i<60)
    {
     4 is obviously less than 60 but it is not working
        id= i+ " min";
    }else if(i>=60 && i<1440)
    {
        id=i+ " hrs";
    }else if(i>=1441 && i<10080)
    {
        id=i+" days";
    }
    else
    {
        id=i+" weeks";
    }
// returns as 4 date
    return id;
}