First off, I want to avoid the use of scriptlets and/or outside libraries. What I'm making is an online polling system, where users can register, log in, and vote on a particular question. That vote is registered and stored in the database. The problem I'm facing is that after I'm retrieving the polls from the Database, I don't know the best way of displaying them in a .jsp page. Again, I want to avoid the use of scriptlets.
Only an "administrator" can create/remove polls. I have a servlet that handles this:
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Database db = new Database();
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String question = request.getParameter("question");
String o1 = request.getParameter("o1");
String o2 = request.getParameter("o2");
String o3 = request.getParameter("o3");
String o4 = request.getParameter("o4");
String o5 = request.getParameter("o5");
if (question == null || o1 == null || o2 == null) {
request.getRequestDispatcher("new.jsp").include(request, response);
out.println("<br>");
out.println("* Poll must have a question and at least 2 choices.");
} else {
int id = (int) System.currentTimeMillis();
db.createPoll(id, question, o1, o2, o3, o4, o5);
request.getRequestDispatcher("new.jsp").include(request, response);
out.println("<br>");
out.println("Poll created.");
}
}
My createPoll method from Database class:
// Method for creating polls. The information is added to the database.
public void createPoll(int id, String question, String o1, String o2, String o3, String o4,
String o5) {
try {
Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
connection = DriverManager
.getConnection("jdbc:derby:C:\\MyDB;create=true;upgrade=true");
String query = "INSERT INTO Polls (id, question, o1, o2, o3, o4, o5) VALUES"
+ "(?,?,?,?,?,?,?)";
preparedStatement = connection.prepareStatement(query);
preparedStatement.setInt(1, id);
preparedStatement.setString(2, question);
preparedStatement.setString(3, o1);
preparedStatement.setString(4, o2);
preparedStatement.setString(5, o3);
preparedStatement.setString(6, o4);
preparedStatement.setString(7, o5);
preparedStatement.executeUpdate();
} catch (Exception e) {
e.printStackTrace();
} finally {
close();
}
}
How I retrieve all the data from the Polls table:
// This method retrives all the polls in the database
// and stores them in an HashMap for further processing
public HashMap<String, ArrayList<String>> getPolls() {
HashMap<String, ArrayList<String>> polls = new HashMap<String, ArrayList<String>>();
try {
Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
connection = DriverManager
.getConnection("jdbc:derby:C:\\MyDB;create=true;upgrade=true");
String query = "SELECT * from Polls";
preparedStatement = connection.prepareStatement(query);
resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
String id = String.valueOf(resultSet.getInt("id"));
String question = resultSet.getString("question");
String o1 = resultSet.getString("o1");
String o2 = resultSet.getString("o2");
String o3 = resultSet.getString("o3");
String o4 = resultSet.getString("o4");
String o5 = resultSet.getString("o5");
polls.put(id, new ArrayList<String>(Arrays.asList(question, o1, o2, o3, o4, o5)));
}
} catch (Exception e) {
e.printStackTrace();
} finally {
close();
}
return polls;
}
So at the end, I'm left with a HashMap containing all the data from Polls. I want these to be displayed in a jsp page. Question first, then all the choices as radio buttons. What is best way of achieving this?
Apologize for the long post!
