Get data from database and return it in form of pojo object

Question

I have a method whose return type is customer which is a pojo. When I get required customerId from database I want to return the customer object with the corresponding data of that customerId. This means it has customer name, address etc. How to proceed for this?

public class Customer verifyCustomerId(cutomerId){
    statement = connection.createStatement();

    resultSet = statement.executeQuery("select customerid from customer");

    while (resultSet.next()) {
        if (cutomerId == resultSet.getInt(1)) {

            // return data corresponding to this id in the form of object of pojo customer

        }
    }

    return null;
}

Answer 1

You can create a Customer object and set your attribute in it like this :

Customer custemer;

if (resultSet.next()) {
   customer = new Customer(resultSet.getInt("customerid"));
}

return custemer;

If you want to get one result you don't need to use while(..) you can make an if instead and your query should have a condition "select customerid from customer where ..." because your query can get multiple results, if you want to get a List you can use while like this :

List<Customer> listCustemer = new ArrayList<>();

while (resultSet.next()) {
   listCustemer.add(new Customer(resultSet.getInt("customerid")));
}

return listCustemer;

EDIT

You can change your constructor and sett your fields you want like name, address and ..., like this : Customer(int id, String name, String address, ...)

So you can use this constructor to create a new Object like so :

listCustemer.add(new Customer(resultSet.getInt("customerid"), 
                 resultSet.getString("name"), resultSet.getString("address"), ...));