Need guidance with Hashmap and resultset

Question

The resultset will return different set of data eg:

> Winter    1001    112 
> Summer    1001    112 
> Autumn    1001    110 
> Spring    1001    111
> Winter    1002    112 
> Summer    1002    116 
> Autumn    1002    110 
> Spring    1002    115
> Winter    1003    112 
> Autumn    1003    111 
> Spring    1003    115 
> Summer    1003    112

and the data i need to display is in this format:

I got data [winter,summer,Autumn,Spring] [data1] [112,112,110,111] [data2] [112,116,110,115] [data3][112,111,115,112]

I was writing the code and this is something what i have got

if (connection != null) {
                System.out.println("Got DB Connection!");
                String selectTableSQL = sql;
                Statement statement = connection.createStatement();
                ResultSet rs = statement.executeQuery(selectTableSQL);
                while (rs.next()) {
                    caltList.add("\""+rs.getString(1)+"\"");
                    dataList.add(rs.getString(3));
                }

                }

String result = "";
String gotData = "I got data "
result = String.format(res,gotData,caltList,dataList);

Can somebody guide with the Hashmap or some approach .. am new to java... and unable to proceed further

Answer 1

I think I would fill a LinkedHashMap<Integer, HashMap<String, Integer> with the data from the ResultSet in this way:

LinkedHashMap [
  => 1001
       => "Winter" => 112
       => "Summer" => 112
       => "Autumn" => 110
       => "Spring" => 111

  => 1002
       => "Winter" => 112
       => "Summer" => 116
       => "Autumn" => 110
       => "Spring" => 115
  => ...
]

Then in a second loop I would create the output which you expect from it. ( [winter,summer,Autumn,Spring] [data1] [112,112,110,111] [data2] [112,116,110,115] ...] ).

That's why I chose a LinkedHashMap because it keeps the order in which you add it's entries. So it is assured that data1 is the first entry in the Map and so on.