java - Trying to get value out of a select option in the same form -

i'm trying value out of select option. doesn't seems able since it's on form. how do ? mean having taking value out of option select.

<strong>select product :</strong>     <select name="stockid">      <c:foreach var="row" items="${stocks1.rowsbyindex}">       <option selected><c:out value="${row[0]}"/></option>      </c:foreach>     </select>     </p> <%!int query = 0; %>  <%            if(request.getparameter("stockid") != null){             connection connection = drivermanager.getconnection(                 "jdbc:derby://localhost:1527/healthdb", "nbuser", "nbuser");              preparedstatement statement = connection.preparestatement("select stockqty stocks stockid = ?");               statement.setstring(1,request.getparameter("stockid"));             resultset resultset =                  statement.executequery( ) ;          if(resultset.next()){             out.print(resultset.getstring("stockqty"));             query = resultset.getint("stockqty");         }  else  out.print("lol");}%>  

1.) can not select items in select selected ! without multiple="multiple"

 <c:foreach var="row" items="${stocks1.rowsbyindex}">   <option selected><c:out value="${row[0]}"/></option>  </c:foreach> 

e.g. topfr[]

<select name = "topfr[]" multiple="multiple">     <option selected="selected">apple</option>     <option>pear</option>     <option selected="selected">peach</option> </select> 

if can have multiple selected name must array here stockid[]

<select name="stockid[]"> 

if <form> array must treat request.getparameter("stockid")as array !

2.) or stockid = int then

you can not pass string field = int

if stockid int !

statement.setstring(1,request.getparameter("stockid")); 

will set string query , string quoted

wrong

select stockqty stocks stockid = "1"  

you need

select stockqty stocks stockid = 1  

try

statement.setint(1,integer.parseint(request.getparameter("stockid")); 

also should test empty !

string res = request.getparameter("stockid"); if(res != null && !res.isempty()){