Spring MVC i.e Get Model object in which only ArrayList attribute must be initialized and remaining attributes should not be initialized

Question

======NewContact.jsp==============0

Here I'm getting the Model object and rendering happly.

======Users.java(Model Class)======1

package com.one.model;
import java.util.ArrayList;
public class Users
{

  private ArrayList<String> al;
  private String x;
  private int y;

  // getters and setters

   }

===============UsersDao.java(Dao interface)========2

package com.one.dao;
import com.one.model.Users;
public interface UsersDao {
   public Users getModified(Users glist);
   }
}

==============UsersDaoImpl.java(Dao Implementation)=======3

package com.one.daoimpl;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import javax.sql.DataSource;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.ResultSetExtractor;
import com.one.dao.UsersDao;
import com.one.model.Users;

public class UsersDaoImpl implements UsersDao {

private JdbcTemplate jdbcTemplate;
public UsersDaoImpl(DataSource dataSource) 
{
    jdbcTemplate = new JdbcTemplate(dataSource);
}


@Override
public Users getModified(Users glist)
{
    String sql1 = "SELECT user_group FROM users";
   //Here I was strucked.
    return glist;
}

}

Here I was strucked. I have JdbcTemplate class obj. This is Spring MVC application. I'm able to executing other queries here,no problem. And displaying the all the values in the view pages no problem. But I need get drop down menu in NewContact.jsp. For that I'm creating Model object in Controller class and Sending that model object to the NewContact.jsp i.e view page. but how can I inject only user_group values from the databse table,assume "users"(is table) and "name,sal,user_group"(are the columns OF "users" table).

Finally, when I am returning an object(i.e object of the Model'Users.java') from the UsersDaoImpl class,only model object "ArrayList al" must be initialized. But x and y variables should not be initialized. I Don't want to use AJAX here.

I've edited your question to format code as code, because you're new here. Next time, format it correctly, and don't post it until it looks correct. — JB Nizet, Sep 02 '15 at 12:53

OPK · Accepted Answer · 2015-09-02T13:05:49.670

0

What you can do here is first to create a DAO implementation that returns a list of objects that you want to display in the drop down menu.Then use Spring annotation @ResponseBody in one of your controller method, and return a json array that contains the values that you want to included in your dropdown.

    @RequestMapping(value = "/url", method = RequestMethod.GET)
    public @ResponseBody List<Object> getObject() {
        //from here call the DAO implementation for returning the object, even tho you suppose to include a service layer.
    }

Now, you gonna need use some jQuery in your JSP:

A simple drop down can be like this:

<script type="text/javascript">
        $(document).ready(
            function() {
                $.getJSON('<spring:url value="your JSON file URL path here"/>', {
                    ajax : 'true'
                }, function(data){
                    var html = '<option value="">--Please select one--</option>';
                    var len = data.length;
                    for (var i = 0; i < len; i++) {
                        html += '<option value="' + data[i].desc + '">'
                                + data[i].desc + '</option>';
                    }
                    html += '</option>';

                    $('#dropDownSelect').html(html);
                });

            });

    </script>

And JSP:

<select id="dropDownSelect"/>

edited Sep 02 '15 at 13:05

answered Sep 02 '15 at 13:00

OPK

4,120
6
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Is it possible without using JQuery,Ajax – Kodali444 Sep 02 '15 at 13:11
Sir, Actually I don't know anything about JQuery,Ajax..etc. – Kodali444 Sep 02 '15 at 13:12
You can have a look at this if u don't want to use jquery, should get you started pretty good: http://www.mkyong.com/spring-mvc/spring-mvc-dropdown-box-example/ – OPK Sep 02 '15 at 13:14
Insted of sending only new object to NewContact.jsp ,I need to send Model Object , in which only ArrayList attribute is initializes with values – Kodali444 Sep 02 '15 at 13:16
No, you can create a list that only contains `UserGroups`, for example, `List list;` And you just need to create a DAO implementation, such as this: `public List getUserGroups(){ ...here you use JDBC to return the data...}` – OPK Sep 02 '15 at 13:26
public List list() { String sql = "SELECT * FROM groups"; List listContact = jdbcTemplate.query(sql, new RowMapper() { @Override public Groups mapRow(ResultSet rs, int rowNum) throws SQLException { Groups glist = new Groups(); glist.setId(rs.getInt("id")); glist.setName(rs.getString("name")); glist.setIs_active(rs.getInt("is_active")); glist.setTenant_id(rs.getLong("tenant_id")); return glist; } }); return listContact; } – Kodali444 Sep 02 '15 at 13:45
public Users getModified(Users glist) { String sqlQuery = "SELECT user_group FROM users"; //++++ return glist; } //++++ here which method of jdbcTemplate class I have to use to pass "sqlQuery" and retrive the 'user_group' column of 'users' table and assign those 'user_group' values to attribute ArrayList of Users Model object. Here I no need to assign any values to 'x and y' of Users Model object. If once this over, then I will get the Users Model Object in New Contacts.jsp with 'x and y' I get the values from user. and "ArrayList" contains the values from DB. – Kodali444 Sep 02 '15 at 14:02
r u using jdbc template? if you are, see this: http://stackoverflow.com/questions/8966821/return-a-list-i-already-have-a-rowmapper-implementation – OPK Sep 02 '15 at 14:07
I think that code is to return the list of objects. my requirement is to return only one object . In that one object only one attribute value initialized. – Kodali444 Sep 02 '15 at 14:37

score 0 · Answer 2 · answered Sep 02 '15 at 13:38

0

I think your best choice is create a form-class to initialize the values after get it. In controller, before adding the form into the model, set the list and give the others at null.

answered Sep 02 '15 at 13:38

Kratul

158
2
13

Can you please provide related url's. Then I can easily get relevant information. I mean i din't use form-class so far. – Kodali444 Sep 02 '15 at 14:35

Spring MVC i.e Get Model object in which only ArrayList attribute must be initialized and remaining attributes should not be initialized

2 Answers2