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POunable to group some values based on some condition
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  1. POunable to group some values based on some condition
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    copied!<p>I have some values return from database as a result set like following</p> <pre><code>**resource_name menu_name menu_group_name** DepartmentAction Department Admin Operation PositionAction Position Admin Operation FoodHabitAction FoodHabits Admin Operation ReligiousAction Religious Admin Operation NationalitiesAction Nationlities Admin Operation </code></pre> <p>I would like to group resource_name and menu_name based on menu_group_name some thing like the following</p> <p>If the menu_group_name is same than group all the corresponding resource_name and menu_mane against to menu_group_name.</p> <p>This is the method i tried,</p> <pre><code>public Map&lt;String,List&gt; getMenuForLoggedinRole(int roleid){ Map&lt;String,List&gt; menuListMap = new LinkedHashMap&lt;String,List&gt;(); List&lt;MenuListViewModel&gt; menuNamesList = new ArrayList&lt;MenuListViewModel&gt;(); MenuListViewModel menuViewModel; Connection connection = getConnection(); PreparedStatement ps = null; ResultSet rs = null; if (connection != null) { try { ps = connection.prepareStatement(" select ar.resource_name,ar.menu_name,mg.menu_group_name " + " from m_application_resources as ar," + " m_menu_groups as mg,m_access_matrix as amatrix " + " where ar.resourceid = amatrix.resourceid and amatrix.roleid=?"); ps.setInt(1, roleid); rs = ps.executeQuery(); if(rs.next()) { String menu_group_name = rs.getString("menu_group_name"); String resource_name = rs.getString("resource_name"); String menu_name = rs.getString("menu_name"); if(menuListMap.containsKey(menu_group_name)){ menuNamesList =(List) menuListMap.get(menu_group_name); menuViewModel = new MenuListViewModel(); menuViewModel.setResource_name(resource_name); menuViewModel.setMenu_name(menu_name); menuNamesList.add(menuViewModel); menuListMap.put(menu_group_name, menuNamesList); }else{ menuViewModel = new MenuListViewModel(); menuViewModel.setResource_name(resource_name); menuViewModel.setMenu_name(menu_name); menuNamesList.add(menuViewModel); menuListMap.put(menu_group_name, menuNamesList); } } } catch (Exception ex) { ex.printStackTrace(); }finally { try { closeConnection(connection, rs, ps); } catch (Exception ex) { ex.printStackTrace(); //use logger here } } } printMap(menuListMap); return menuListMap; } </code></pre> <p>But it is not giving me the disired output.</p> <p>My view model:</p> <pre><code>public class MenuListViewModel { private String resource_name = ""; private String menu_name = ""; public String getResource_name() { return resource_name; } public void setResource_name(String resource_name) { this.resource_name = resource_name; } public String getMenu_name() { return menu_name; } public void setMenu_name(String menu_name) { this.menu_name = menu_name; } } </code></pre> <p>and </p> <pre><code> public static void printMap(Map mp) { List menuList = new ArrayList(); MenuListViewModel model; Iterator it = mp.entrySet().iterator(); while (it.hasNext()) { Map.Entry pairs = (Map.Entry)it.next(); menuList =(List) pairs.getValue(); for(int i=0;i&lt;=menuList.size();i++){ model =(MenuListViewModel) menuList.get(i); System.out.println("Resource_name : "+model.getResource_name()); System.out.println("Menu_name : "+model.getMenu_name()); } System.out.println(pairs.getKey() + " = " + pairs.getValue()); it.remove(); // avoids a ConcurrentModificationException } } </code></pre> <p>Please help.</p>
 

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