primefaces - Jsf dataTable sortby, I want (1,2,3,4,10,15), I get (1,10,15,2,3,4). How to solve -

my jsf code goes this:

<p:datatable var="result" value="#{timerconfigurationjoblist.model}" rows="10"                          paginator="true" paginatorposition="bottom"                          paginatortemplate="{rowsperpagedropdown} {firstpagelink} {previouspagelink} {currentpagereport} {nextpagelink} {lastpagelink}"                          rowsperpagetemplate="10,20,50" id="approvaltable" lazy="true">                            <p:column sortby="#{result.jobid}">                     <f:facet name="header">                         <h:outputtext value="#{msg['content.joblist.jobid']}"/>                     </f:facet>                 </p:column >  </p:datatable> 

the result :

as can seen in picture: '123' higher '2', '4', '7' , '9'. want come right @ end, 'numerically' sorted.

am using java , jsf 2.

edit: in lazy model found this:

@override     public final list<t> load(int first, int pagesize, string sortfield, sortorder sortorder,             final map<string, object> filters) {          map<string, sort> sorts = new hashmap<>();          if (sortfield != null) {             if (sortorder.equals(sortorder.ascending)) {                 sorts.put(sortfield, sort.asc);             } else if (sortorder.equals(sortorder.descending)) {                 sorts.put(sortfield, sort.desc);             }             // unsorted can ignored         } 

there multiple ways solve issue:

1. change type of column mentioned @kukeltje. not sure whether want change schema.
2. use sortfunction attribute of column provide custom sorting.
3. pass sorted list of jsf component.